fixx v1

backend/server.js

@@ -674,6 +674,9 @@ function normalizeAssetRequestStatus(value) {
     if (normalized === 'approved' || normalized === 'approve' || normalized === 'accept' || normalized === 'accepted') {
         return 'approved';
     }
+    if (normalized === 'returned' || normalized === 'return_done' || normalized === 'done' || normalized === 'da_tra') {
+        return 'returned';
+    }
     if (normalized === 'rejected' || normalized === 'reject' || normalized === 'declined') {
         return 'rejected';
     }
@@ -1787,6 +1790,7 @@ async function createTables() {
                 RequestStatus NVARCHAR(20) NOT NULL DEFAULT 'pending',
                 BorrowerName NVARCHAR(100) NOT NULL,
                 BorrowQuantity INT NOT NULL DEFAULT 1,
+                ReturnedQuantity INT NOT NULL DEFAULT 0,
                 Unit NVARCHAR(50),
                 BorrowDate DATE NOT NULL DEFAULT CAST(GETDATE() AS DATE),
                 RequestNote NVARCHAR(500) NULL,
@@ -1803,6 +1807,20 @@ async function createTables() {
             )
          END`,
 
+        // Asset Borrow/Return Links Table
+        `IF NOT EXISTS (SELECT * FROM sys.tables WHERE name = 'AssetBorrowRequestLinks')
+         BEGIN
+            CREATE TABLE AssetBorrowRequestLinks (
+                LinkId INT PRIMARY KEY IDENTITY(1,1),
+                BorrowId INT NOT NULL,
+                ReturnId INT NOT NULL,
+                Quantity INT NOT NULL DEFAULT 1,
+                CreatedDate DATETIME NOT NULL DEFAULT GETDATE(),
+                FOREIGN KEY (BorrowId) REFERENCES AssetBorrowRequests(BorrowId) ON DELETE NO ACTION,
+                FOREIGN KEY (ReturnId) REFERENCES AssetBorrowRequests(BorrowId) ON DELETE NO ACTION
+            )
+         END`,
+
         // Asset Export History Table
         `IF NOT EXISTS (SELECT * FROM sys.tables WHERE name = 'AssetExportHistory')
          BEGIN
@@ -1878,6 +1896,9 @@ async function createTables() {
         await pool.request().query(`IF NOT EXISTS (SELECT * FROM sys.indexes WHERE name = 'IX_AssetBorrowRequests_BorrowDate') CREATE INDEX IX_AssetBorrowRequests_BorrowDate ON AssetBorrowRequests(BorrowDate DESC);`);
         await pool.request().query(`IF NOT EXISTS (SELECT * FROM sys.indexes WHERE name = 'IX_AssetBorrowRequests_RequestStatus') CREATE INDEX IX_AssetBorrowRequests_RequestStatus ON AssetBorrowRequests(RequestStatus);`);
         await pool.request().query(`IF NOT EXISTS (SELECT * FROM sys.indexes WHERE name = 'IX_AssetBorrowRequests_RequestType') CREATE INDEX IX_AssetBorrowRequests_RequestType ON AssetBorrowRequests(RequestType);`);
+        await pool.request().query(`IF NOT EXISTS (SELECT * FROM sys.indexes WHERE name = 'IX_AssetBorrowRequestLinks_BorrowId') CREATE INDEX IX_AssetBorrowRequestLinks_BorrowId ON AssetBorrowRequestLinks(BorrowId);`);
+        await pool.request().query(`IF NOT EXISTS (SELECT * FROM sys.indexes WHERE name = 'IX_AssetBorrowRequestLinks_ReturnId') CREATE INDEX IX_AssetBorrowRequestLinks_ReturnId ON AssetBorrowRequestLinks(ReturnId);`);
+        await pool.request().query(`IF NOT EXISTS (SELECT * FROM sys.indexes WHERE name = 'UX_AssetBorrowRequestLinks_BorrowReturn') CREATE UNIQUE INDEX UX_AssetBorrowRequestLinks_BorrowReturn ON AssetBorrowRequestLinks(BorrowId, ReturnId);`);
     } catch (err) {
         console.error('AssetBorrowRequests index creation error:', err.message);
     }
@@ -1913,6 +1934,7 @@ async function createTables() {
         await pool.request().query(`IF COL_LENGTH('dbo.AssetBorrowRequests','BorrowDate') IS NULL ALTER TABLE AssetBorrowRequests ADD BorrowDate DATE NOT NULL CONSTRAINT DF_AssetBorrowRequests_BorrowDate DEFAULT(CAST(GETDATE() AS DATE));`);
         await pool.request().query(`IF COL_LENGTH('dbo.AssetBorrowRequests','RequestType') IS NULL ALTER TABLE AssetBorrowRequests ADD RequestType NVARCHAR(20) NOT NULL CONSTRAINT DF_AssetBorrowRequests_RequestType DEFAULT('borrow');`);
         await pool.request().query(`IF COL_LENGTH('dbo.AssetBorrowRequests','RequestStatus') IS NULL ALTER TABLE AssetBorrowRequests ADD RequestStatus NVARCHAR(20) NOT NULL CONSTRAINT DF_AssetBorrowRequests_RequestStatus DEFAULT('approved');`);
+        await pool.request().query(`IF COL_LENGTH('dbo.AssetBorrowRequests','ReturnedQuantity') IS NULL ALTER TABLE AssetBorrowRequests ADD ReturnedQuantity INT NOT NULL CONSTRAINT DF_AssetBorrowRequests_ReturnedQuantity DEFAULT(0);`);
         await pool.request().query(`IF COL_LENGTH('dbo.AssetBorrowRequests','RequestNote') IS NULL ALTER TABLE AssetBorrowRequests ADD RequestNote NVARCHAR(500) NULL;`);
         await pool.request().query(`IF COL_LENGTH('dbo.AssetBorrowRequests','RejectReason') IS NULL ALTER TABLE AssetBorrowRequests ADD RejectReason NVARCHAR(1000) NULL;`);
         await pool.request().query(`IF COL_LENGTH('dbo.AssetBorrowRequests','ProcessedBy') IS NULL ALTER TABLE AssetBorrowRequests ADD ProcessedBy INT NULL;`);
@@ -1929,6 +1951,20 @@ async function createTables() {
             FOREIGN KEY (ProcessedBy) REFERENCES Users(UserId) ON DELETE SET NULL;
         `);
         await pool.request().query(`IF COL_LENGTH('dbo.AssetBorrowRequests','UpdatedDate') IS NULL ALTER TABLE AssetBorrowRequests ADD UpdatedDate DATETIME NOT NULL CONSTRAINT DF_AssetBorrowRequests_UpdatedDate DEFAULT(GETDATE());`);
+        await pool.request().query(`
+            IF NOT EXISTS (SELECT * FROM sys.tables WHERE name = 'AssetBorrowRequestLinks')
+            BEGIN
+                CREATE TABLE AssetBorrowRequestLinks (
+                    LinkId INT PRIMARY KEY IDENTITY(1,1),
+                    BorrowId INT NOT NULL,
+                    ReturnId INT NOT NULL,
+                    Quantity INT NOT NULL CONSTRAINT DF_AssetBorrowRequestLinks_Quantity DEFAULT(1),
+                    CreatedDate DATETIME NOT NULL CONSTRAINT DF_AssetBorrowRequestLinks_CreatedDate DEFAULT(GETDATE()),
+                    FOREIGN KEY (BorrowId) REFERENCES AssetBorrowRequests(BorrowId) ON DELETE NO ACTION,
+                    FOREIGN KEY (ReturnId) REFERENCES AssetBorrowRequests(BorrowId) ON DELETE NO ACTION
+                );
+            END
+        `);
         await pool.request().query(`IF COL_LENGTH('dbo.AssetExportHistory','AssetCode') IS NULL ALTER TABLE AssetExportHistory ADD AssetCode NVARCHAR(100) NULL;`);
         await pool.request().query(`IF COL_LENGTH('dbo.AssetExportHistory','AssetName') IS NULL ALTER TABLE AssetExportHistory ADD AssetName NVARCHAR(255) NULL;`);
         await pool.request().query(`IF COL_LENGTH('dbo.AssetExportHistory','ExportQuantity') IS NULL ALTER TABLE AssetExportHistory ADD ExportQuantity INT NOT NULL CONSTRAINT DF_AssetExportHistory_ExportQuantity DEFAULT(1);`);
@@ -1959,6 +1995,68 @@ async function createTables() {
         `);
         await pool.request().query(`UPDATE AssetBorrowRequests SET RequestType = ISNULL(NULLIF(LTRIM(RTRIM(RequestType)), ''), 'borrow');`);
         await pool.request().query(`UPDATE AssetBorrowRequests SET RequestStatus = ISNULL(NULLIF(LTRIM(RTRIM(RequestStatus)), ''), 'approved');`);
+        await pool.request().query(`UPDATE AssetBorrowRequests SET ReturnedQuantity = 0 WHERE ReturnedQuantity IS NULL OR ReturnedQuantity < 0;`);
+        await pool.request().query(`
+            IF OBJECT_ID('dbo.AssetBorrowRequestLinks', 'U') IS NOT NULL
+            BEGIN
+                INSERT INTO AssetBorrowRequestLinks (BorrowId, ReturnId, Quantity)
+                SELECT matchedBorrow.BorrowId,
+                       ret.BorrowId,
+                       CASE
+                           WHEN ISNULL(ret.BorrowQuantity, 0) <= 0 THEN 1
+                           WHEN ISNULL(ret.BorrowQuantity, 0) > ISNULL(matchedBorrow.BorrowQuantity, 0) THEN ISNULL(matchedBorrow.BorrowQuantity, 0)
+                           ELSE ISNULL(ret.BorrowQuantity, 0)
+                       END
+                FROM AssetBorrowRequests ret
+                CROSS APPLY (
+                    SELECT TOP 1 b.BorrowId, b.BorrowQuantity
+                    FROM AssetBorrowRequests b
+                    WHERE LOWER(LTRIM(RTRIM(ISNULL(b.RequestType, '')))) = 'borrow'
+                      AND LOWER(LTRIM(RTRIM(ISNULL(b.RequestStatus, '')))) IN ('approved', 'returned')
+                      AND b.AssetId = ret.AssetId
+                      AND (
+                            (ret.CreatedBy IS NOT NULL AND b.CreatedBy = ret.CreatedBy)
+                            OR LOWER(LTRIM(RTRIM(ISNULL(b.BorrowerName, '')))) = LOWER(LTRIM(RTRIM(ISNULL(ret.BorrowerName, ''))))
+                      )
+                      AND b.BorrowDate <= ret.BorrowDate
+                    ORDER BY b.BorrowDate DESC, b.CreatedDate DESC, b.BorrowId DESC
+                ) matchedBorrow
+                WHERE LOWER(LTRIM(RTRIM(ISNULL(ret.RequestType, '')))) = 'return'
+                  AND LOWER(LTRIM(RTRIM(ISNULL(ret.RequestStatus, '')))) IN ('pending', 'approved')
+                  AND NOT EXISTS (
+                        SELECT 1
+                        FROM AssetBorrowRequestLinks existed
+                        WHERE existed.ReturnId = ret.BorrowId
+                  )
+                  AND NOT EXISTS (
+                        SELECT 1
+                        FROM AssetBorrowRequestLinks duplicateLink
+                        WHERE duplicateLink.ReturnId = ret.BorrowId
+                          AND duplicateLink.BorrowId = matchedBorrow.BorrowId
+                  );
+
+                UPDATE borrowRows
+                SET ReturnedQuantity = CASE
+                        WHEN summary.ReturnedQuantity > ISNULL(borrowRows.BorrowQuantity, 0) THEN ISNULL(borrowRows.BorrowQuantity, 0)
+                        ELSE summary.ReturnedQuantity
+                    END,
+                    RequestStatus = CASE
+                        WHEN summary.ReturnedQuantity >= ISNULL(borrowRows.BorrowQuantity, 0)
+                            THEN 'returned'
+                        ELSE borrowRows.RequestStatus
+                    END,
+                    UpdatedDate = GETDATE()
+                FROM AssetBorrowRequests borrowRows
+                INNER JOIN (
+                    SELECT links.BorrowId, SUM(ISNULL(links.Quantity, 0)) AS ReturnedQuantity
+                    FROM AssetBorrowRequestLinks links
+                    INNER JOIN AssetBorrowRequests returns ON returns.BorrowId = links.ReturnId
+                    WHERE LOWER(LTRIM(RTRIM(ISNULL(returns.RequestStatus, '')))) = 'approved'
+                    GROUP BY links.BorrowId
+                ) summary ON summary.BorrowId = borrowRows.BorrowId
+                WHERE LOWER(LTRIM(RTRIM(ISNULL(borrowRows.RequestType, '')))) = 'borrow';
+            END
+        `);
         await pool.request().query(`UPDATE AssetInventory SET EndingBalance = ISNULL(EndingBalance, ISNULL(Quantity, 0));`);
         await pool.request().query(`UPDATE AssetInventory SET Quantity = ISNULL(NULLIF(Quantity, 0), EndingBalance);`);
         await pool.request().query(`UPDATE AssetInventory SET UsedQuantity = CASE WHEN UsedQuantity < 0 THEN 0 ELSE ISNULL(UsedQuantity, 0) END;`);
@@ -3632,6 +3730,17 @@ app.get('/api/asset-borrows', async (req, res) => {
                 br.RequestStatus,
                 br.BorrowerName,
                 br.BorrowQuantity,
+                ISNULL(br.ReturnedQuantity, 0) AS ReturnedQuantity,
+                CASE
+                    WHEN LOWER(LTRIM(RTRIM(ISNULL(br.RequestType, '')))) = 'borrow'
+                        THEN CASE
+                            WHEN ISNULL(br.BorrowQuantity, 0) - ISNULL(br.ReturnedQuantity, 0) < 0 THEN 0
+                            ELSE ISNULL(br.BorrowQuantity, 0) - ISNULL(br.ReturnedQuantity, 0)
+                        END
+                    ELSE 0
+                END AS RemainingQuantity,
+                ISNULL(returnSummary.ReturnCount, 0) AS RelatedReturnCount,
+                ISNULL(borrowSummary.BorrowCount, 0) AS RelatedBorrowCount,
                 COALESCE(NULLIF(LTRIM(RTRIM(br.Unit)), ''), ai.Unit) AS Unit,
                 br.BorrowDate,
                 br.RequestNote,
@@ -3643,6 +3752,36 @@ app.get('/api/asset-borrows', async (req, res) => {
                 br.CreatedDate
             FROM AssetBorrowRequests br
             LEFT JOIN AssetInventory ai ON ai.AssetId = br.AssetId
+            OUTER APPLY (
+                SELECT COUNT(1) AS ReturnCount
+                FROM AssetBorrowRequests rr
+                WHERE LOWER(LTRIM(RTRIM(ISNULL(br.RequestType, '')))) = 'borrow'
+                  AND LOWER(LTRIM(RTRIM(ISNULL(rr.RequestType, '')))) = 'return'
+                  AND LOWER(LTRIM(RTRIM(ISNULL(rr.RequestStatus, '')))) IN ('pending', 'approved')
+                  AND (
+                        EXISTS (
+                            SELECT 1
+                            FROM AssetBorrowRequestLinks l
+                            WHERE l.BorrowId = br.BorrowId
+                              AND l.ReturnId = rr.BorrowId
+                        )
+                        OR (
+                            rr.AssetId = br.AssetId
+                            AND rr.BorrowDate >= br.BorrowDate
+                            AND (
+                                (rr.CreatedBy IS NOT NULL AND br.CreatedBy IS NOT NULL AND rr.CreatedBy = br.CreatedBy)
+                                OR LOWER(LTRIM(RTRIM(ISNULL(rr.BorrowerName, '')))) = LOWER(LTRIM(RTRIM(ISNULL(br.BorrowerName, ''))))
+                            )
+                        )
+                  )
+            ) returnSummary
+            OUTER APPLY (
+                SELECT COUNT(1) AS BorrowCount
+                FROM AssetBorrowRequestLinks l
+                INNER JOIN AssetBorrowRequests bb ON bb.BorrowId = l.BorrowId
+                WHERE l.ReturnId = br.BorrowId
+                  AND LOWER(LTRIM(RTRIM(ISNULL(bb.RequestType, '')))) = 'borrow'
+            ) borrowSummary
             ${canManageRequests ? '' : 'WHERE br.CreatedBy = @requesterId'}
             ORDER BY br.CreatedDate DESC, br.BorrowId DESC
         `);
@@ -3653,7 +3792,182 @@ app.get('/api/asset-borrows', async (req, res) => {
     }
 });
 
+app.get('/api/asset-borrows/:id/history', async (req, res) => {
+    try {
+        const requesterRole = normalizeRole(req.headers['x-user-role'] || req.query.userRole);
+        const requesterId = getUserIdFromRequest(req);
+        const canManageRequests = requesterRole === 'admin' || requesterRole === 'asset';
+        const borrowId = Number(req.params.id);
+
+        if (!Number.isInteger(borrowId) || borrowId <= 0) {
+            return res.status(400).json({ success: false, message: 'Ma don khong hop le' });
+        }
+
+        if (!canManageRequests && (!Number.isInteger(requesterId) || requesterId <= 0)) {
+            return res.status(401).json({ success: false, message: 'Yeu cau xac thuc nguoi dung' });
+        }
+
+        const targetRequest = pool.request()
+            .input('borrowId', sql.Int, borrowId)
+            .input('requesterId', sql.Int, requesterId || -1);
+
+        const targetResult = await targetRequest.query(`
+            SELECT TOP 1
+                br.BorrowId,
+                br.AssetId,
+                ai.AssetCode,
+                ai.AssetName,
+                br.RequestType,
+                br.RequestStatus,
+                br.BorrowerName,
+                br.BorrowQuantity,
+                ISNULL(br.ReturnedQuantity, 0) AS ReturnedQuantity,
+                CASE
+                    WHEN LOWER(LTRIM(RTRIM(ISNULL(br.RequestType, '')))) = 'borrow'
+                        THEN CASE
+                            WHEN ISNULL(br.BorrowQuantity, 0) - ISNULL(br.ReturnedQuantity, 0) < 0 THEN 0
+                            ELSE ISNULL(br.BorrowQuantity, 0) - ISNULL(br.ReturnedQuantity, 0)
+                        END
+                    ELSE 0
+                END AS RemainingQuantity,
+                COALESCE(NULLIF(LTRIM(RTRIM(br.Unit)), ''), ai.Unit) AS Unit,
+                br.BorrowDate,
+                br.RequestNote,
+                br.RejectReason,
+                br.CreatedBy,
+                br.ProcessedBy,
+                br.ProcessedByName,
+                br.ProcessedDate,
+                br.CreatedDate
+            FROM AssetBorrowRequests br
+            LEFT JOIN AssetInventory ai ON ai.AssetId = br.AssetId
+            WHERE br.BorrowId = @borrowId
+              ${canManageRequests ? '' : 'AND br.CreatedBy = @requesterId'}
+        `);
+
+        const target = targetResult.recordset?.[0];
+        if (!target) {
+            return res.status(404).json({ success: false, message: 'Khong tim thay don' });
+        }
+
+        const targetType = normalizeAssetRequestType(target.RequestType);
+        const relatedRequest = pool.request()
+            .input('borrowId', sql.Int, borrowId)
+            .input('assetId', sql.Int, Number(target.AssetId) || -1)
+            .input('borrowerName', sql.NVarChar, String(target.BorrowerName || '').trim())
+            .input('createdBy', sql.Int, Number.isInteger(Number(target.CreatedBy)) ? Number(target.CreatedBy) : null)
+            .input('borrowDate', sql.Date, target.BorrowDate || null)
+            .input('targetType', sql.NVarChar, targetType)
+            .input('requesterId', sql.Int, requesterId || -1);
+
+        const relatedResult = await relatedRequest.query(`
+            ;WITH linkedIds AS (
+                SELECT l.BorrowId AS RelatedId
+                FROM AssetBorrowRequestLinks l
+                WHERE l.ReturnId = @borrowId
+                UNION
+                SELECT l.ReturnId AS RelatedId
+                FROM AssetBorrowRequestLinks l
+                WHERE l.BorrowId = @borrowId
+            )
+            SELECT DISTINCT
+                br.BorrowId,
+                br.AssetId,
+                ai.AssetCode,
+                ai.AssetName,
+                br.RequestType,
+                br.RequestStatus,
+                br.BorrowerName,
+                br.BorrowQuantity,
+                ISNULL(br.ReturnedQuantity, 0) AS ReturnedQuantity,
+                CASE
+                    WHEN LOWER(LTRIM(RTRIM(ISNULL(br.RequestType, '')))) = 'borrow'
+                        THEN CASE
+                            WHEN ISNULL(br.BorrowQuantity, 0) - ISNULL(br.ReturnedQuantity, 0) < 0 THEN 0
+                            ELSE ISNULL(br.BorrowQuantity, 0) - ISNULL(br.ReturnedQuantity, 0)
+                        END
+                    ELSE 0
+                END AS RemainingQuantity,
+                COALESCE(NULLIF(LTRIM(RTRIM(br.Unit)), ''), ai.Unit) AS Unit,
+                br.BorrowDate,
+                br.RequestNote,
+                br.RejectReason,
+                br.CreatedBy,
+                br.ProcessedBy,
+                br.ProcessedByName,
+                br.ProcessedDate,
+                br.CreatedDate
+            FROM AssetBorrowRequests br
+            LEFT JOIN AssetInventory ai ON ai.AssetId = br.AssetId
+            WHERE (
+                    br.BorrowId = @borrowId
+                    OR br.BorrowId IN (SELECT RelatedId FROM linkedIds)
+                    OR (
+                        br.AssetId = @assetId
+                        AND LOWER(LTRIM(RTRIM(ISNULL(br.BorrowerName, '')))) = LOWER(LTRIM(RTRIM(ISNULL(@borrowerName, ''))))
+                        AND (
+                            @createdBy IS NULL
+                            OR br.CreatedBy = @createdBy
+                            OR br.CreatedBy IS NULL
+                        )
+                        AND (
+                            (@targetType = 'borrow'
+                                AND LOWER(LTRIM(RTRIM(ISNULL(br.RequestType, '')))) = 'return'
+                                AND br.BorrowDate >= @borrowDate)
+                            OR
+                            (@targetType = 'return'
+                                AND LOWER(LTRIM(RTRIM(ISNULL(br.RequestType, '')))) = 'borrow'
+                                AND br.BorrowDate <= @borrowDate)
+                        )
+                    )
+                )
+              ${canManageRequests ? '' : 'AND br.CreatedBy = @requesterId'}
+            ORDER BY br.BorrowDate ASC, br.CreatedDate ASC, br.BorrowId ASC
+        `);
+
+        const linkResult = await pool.request()
+            .input('borrowId', sql.Int, borrowId)
+            .query(`
+                SELECT
+                    l.LinkId,
+                    l.BorrowId,
+                    l.ReturnId,
+                    l.Quantity,
+                    l.CreatedDate
+                FROM AssetBorrowRequestLinks l
+                WHERE l.BorrowId = @borrowId
+                   OR l.ReturnId = @borrowId
+                   OR l.BorrowId IN (
+                        SELECT linked.BorrowId
+                        FROM AssetBorrowRequestLinks linked
+                        WHERE linked.ReturnId = @borrowId
+                   )
+                   OR l.ReturnId IN (
+                        SELECT linked.ReturnId
+                        FROM AssetBorrowRequestLinks linked
+                        WHERE linked.BorrowId = @borrowId
+                   )
+                ORDER BY l.CreatedDate ASC, l.LinkId ASC
+            `);
+
+        const relatedRows = Array.isArray(relatedResult.recordset) ? relatedResult.recordset : [];
+        res.json({
+            success: true,
+            data: {
+                request: target,
+                borrowRequests: relatedRows.filter(item => normalizeAssetRequestType(item.RequestType) === 'borrow'),
+                returnRequests: relatedRows.filter(item => normalizeAssetRequestType(item.RequestType) === 'return'),
+                links: Array.isArray(linkResult.recordset) ? linkResult.recordset : []
+            }
+        });
+    } catch (err) {
+        res.status(500).json({ success: false, message: err.message });
+    }
+});
+
 app.post('/api/asset-borrows', async (req, res) => {
+    let transaction;
+
     try {
         const createdBy = getUserIdFromRequest(req);
         const actorName = await getUserDisplayNameById(createdBy);
@@ -3738,7 +4052,60 @@ app.post('/api/asset-borrows', async (req, res) => {
             }
         }
 
-        const insertResult = await pool.request()
+        transaction = new sql.Transaction(pool);
+        await transaction.begin();
+
+        let returnLinkRows = [];
+        if (requestType === 'return') {
+            const createdByValue = Number.isInteger(Number(createdBy)) ? Number(createdBy) : null;
+            const linkableResult = await new sql.Request(transaction)
+                .input('assetId', sql.Int, assetId)
+                .input('borrowerName', sql.NVarChar, borrowerName)
+                .input('createdBy', sql.Int, createdByValue)
+                .query(`
+                    SELECT
+                        borrowRows.BorrowId,
+                        borrowRows.BorrowQuantity,
+                        ISNULL(borrowRows.ReturnedQuantity, 0) AS ReturnedQuantity,
+                        ISNULL(activeReturns.ActiveReturnQuantity, 0) AS ActiveReturnQuantity
+                    FROM AssetBorrowRequests borrowRows WITH (UPDLOCK, HOLDLOCK)
+                    OUTER APPLY (
+                        SELECT SUM(ISNULL(links.Quantity, 0)) AS ActiveReturnQuantity
+                        FROM AssetBorrowRequestLinks links
+                        INNER JOIN AssetBorrowRequests returnRows ON returnRows.BorrowId = links.ReturnId
+                        WHERE links.BorrowId = borrowRows.BorrowId
+                          AND LOWER(LTRIM(RTRIM(ISNULL(returnRows.RequestStatus, '')))) IN ('pending', 'approved')
+                    ) activeReturns
+                    WHERE borrowRows.AssetId = @assetId
+                      AND LOWER(LTRIM(RTRIM(ISNULL(borrowRows.RequestType, '')))) = 'borrow'
+                      AND LOWER(LTRIM(RTRIM(ISNULL(borrowRows.RequestStatus, '')))) IN ('approved', 'returned')
+                      AND LOWER(LTRIM(RTRIM(ISNULL(borrowRows.BorrowerName, '')))) = LOWER(LTRIM(RTRIM(ISNULL(@borrowerName, ''))))
+                      AND (
+                            @createdBy IS NULL
+                            OR borrowRows.CreatedBy = @createdBy
+                            OR borrowRows.CreatedBy IS NULL
+                      )
+                    ORDER BY borrowRows.BorrowDate ASC, borrowRows.CreatedDate ASC, borrowRows.BorrowId ASC
+                `);
+
+            returnLinkRows = Array.isArray(linkableResult.recordset) ? linkableResult.recordset : [];
+            const availableReturnQuantity = returnLinkRows.reduce((sum, row) => {
+                const originalQuantity = parseNonNegativeInteger(row.BorrowQuantity, 0);
+                const returnedQuantity = parseNonNegativeInteger(row.ReturnedQuantity, 0);
+                const activeReturnQuantity = parseNonNegativeInteger(row.ActiveReturnQuantity, 0);
+                return sum + Math.max(originalQuantity - Math.max(returnedQuantity, activeReturnQuantity), 0);
+            }, 0);
+
+            if (borrowQuantity > availableReturnQuantity) {
+                await transaction.rollback();
+                return res.status(400).json({
+                    success: false,
+                    message: `So luong tra (${borrowQuantity}) vuot qua so luong con co the tao don tra (${availableReturnQuantity}). Co the da co don tra dang cho duyet.`
+                });
+            }
+        }
+
+        const insertResult = await new sql.Request(transaction)
             .input('assetId', sql.Int, assetId)
             .input('requestType', sql.NVarChar, requestType)
             .input('requestStatus', sql.NVarChar, 'pending')
@@ -3773,16 +4140,58 @@ app.post('/api/asset-borrows', async (req, res) => {
                 SELECT SCOPE_IDENTITY() AS BorrowId;
             `);
 
+        const createdRequestId = Number(insertResult.recordset?.[0]?.BorrowId) || null;
+
+        if (requestType === 'return' && createdRequestId) {
+            let remainingToLink = borrowQuantity;
+            for (const row of returnLinkRows) {
+                if (remainingToLink <= 0) {
+                    break;
+                }
+
+                const borrowRequestId = Number(row.BorrowId);
+                const originalQuantity = parseNonNegativeInteger(row.BorrowQuantity, 0);
+                const returnedQuantity = parseNonNegativeInteger(row.ReturnedQuantity, 0);
+                const activeReturnQuantity = parseNonNegativeInteger(row.ActiveReturnQuantity, 0);
+                const availableQuantity = Math.max(originalQuantity - Math.max(returnedQuantity, activeReturnQuantity), 0);
+                const linkedQuantity = Math.min(availableQuantity, remainingToLink);
+
+                if (!Number.isInteger(borrowRequestId) || borrowRequestId <= 0 || linkedQuantity <= 0) {
+                    continue;
+                }
+
+                await new sql.Request(transaction)
+                    .input('borrowId', sql.Int, borrowRequestId)
+                    .input('returnId', sql.Int, createdRequestId)
+                    .input('quantity', sql.Int, linkedQuantity)
+                    .query(`
+                        INSERT INTO AssetBorrowRequestLinks (BorrowId, ReturnId, Quantity)
+                        VALUES (@borrowId, @returnId, @quantity);
+                    `);
+
+                remainingToLink -= linkedQuantity;
+            }
+        }
+
+        await transaction.commit();
+
         res.json({
             success: true,
             message: requestType === 'return'
                 ? 'Tao don tra tai san thanh cong. Don dang cho xu ly.'
                 : 'Tao don muon tai san thanh cong. Don dang cho xu ly.',
             data: {
-                borrowId: insertResult.recordset?.[0]?.BorrowId || null
+                borrowId: createdRequestId
             }
         });
     } catch (err) {
+        if (transaction) {
+            try {
+                await transaction.rollback();
+            } catch (rollbackErr) {
+                // Ignore rollback errors when transaction already finished.
+            }
+        }
         res.status(500).json({ success: false, message: err.message });
     }
 });
@@ -3827,6 +4236,7 @@ app.post('/api/asset-borrows/:id/process', requireAssetOrAdmin, async (req, res)
                     br.BorrowQuantity,
                     br.BorrowDate,
                     br.Unit,
+                    br.CreatedBy,
                     ai.AssetCode,
                     ai.AssetName,
                     ai.Quantity,
@@ -3990,6 +4400,133 @@ app.post('/api/asset-borrows/:id/process', requireAssetOrAdmin, async (req, res)
                             UpdatedDate = GETDATE()
                         WHERE AssetId = @assetId
                     `);
+
+                const existingReturnLinksResult = await new sql.Request(transaction)
+                    .input('returnId', sql.Int, borrowId)
+                    .query(`
+                        SELECT
+                            links.BorrowId,
+                            links.Quantity,
+                            borrowRows.BorrowQuantity,
+                            ISNULL(borrowRows.ReturnedQuantity, 0) AS ReturnedQuantity
+                        FROM AssetBorrowRequestLinks links
+                        INNER JOIN AssetBorrowRequests borrowRows WITH (UPDLOCK, HOLDLOCK)
+                            ON borrowRows.BorrowId = links.BorrowId
+                        WHERE links.ReturnId = @returnId
+                        ORDER BY borrowRows.BorrowDate ASC, borrowRows.CreatedDate ASC, borrowRows.BorrowId ASC
+                    `);
+
+                const existingReturnLinks = Array.isArray(existingReturnLinksResult.recordset)
+                    ? existingReturnLinksResult.recordset
+                    : [];
+
+                if (existingReturnLinks.length) {
+                    for (const linkRow of existingReturnLinks) {
+                        const borrowRequestId = Number(linkRow.BorrowId);
+                        const linkedQuantity = parseNonNegativeInteger(linkRow.Quantity, 0);
+                        if (!Number.isInteger(borrowRequestId) || borrowRequestId <= 0 || linkedQuantity <= 0) {
+                            continue;
+                        }
+
+                        await new sql.Request(transaction)
+                            .input('borrowId', sql.Int, borrowRequestId)
+                            .input('quantity', sql.Int, linkedQuantity)
+                            .query(`
+                                UPDATE AssetBorrowRequests
+                                SET ReturnedQuantity = CASE
+                                        WHEN ISNULL(ReturnedQuantity, 0) + @quantity > ISNULL(BorrowQuantity, 0)
+                                            THEN ISNULL(BorrowQuantity, 0)
+                                        ELSE ISNULL(ReturnedQuantity, 0) + @quantity
+                                    END,
+                                    RequestStatus = CASE
+                                        WHEN ISNULL(ReturnedQuantity, 0) + @quantity >= ISNULL(BorrowQuantity, 0)
+                                            THEN 'returned'
+                                        ELSE RequestStatus
+                                    END,
+                                    UpdatedDate = GETDATE()
+                                WHERE BorrowId = @borrowId
+                            `);
+                    }
+                } else {
+                    let remainingToLink = requestQuantity;
+                    const createdByValue = Number.isInteger(Number(targetRequest.CreatedBy))
+                        ? Number(targetRequest.CreatedBy)
+                        : null;
+                    const borrowRowsResult = await new sql.Request(transaction)
+                        .input('assetId', sql.Int, targetRequest.AssetId)
+                        .input('borrowerName', sql.NVarChar, borrowerName)
+                        .input('createdBy', sql.Int, createdByValue)
+                        .query(`
+                            SELECT
+                                BorrowId,
+                                BorrowQuantity,
+                                ISNULL(ReturnedQuantity, 0) AS ReturnedQuantity
+                            FROM AssetBorrowRequests WITH (UPDLOCK, HOLDLOCK)
+                            WHERE AssetId = @assetId
+                              AND LOWER(LTRIM(RTRIM(ISNULL(RequestType, '')))) = 'borrow'
+                              AND LOWER(LTRIM(RTRIM(ISNULL(RequestStatus, '')))) IN ('approved', 'returned')
+                              AND ISNULL(BorrowQuantity, 0) > ISNULL(ReturnedQuantity, 0)
+                              AND LOWER(LTRIM(RTRIM(ISNULL(BorrowerName, '')))) = LOWER(LTRIM(RTRIM(ISNULL(@borrowerName, ''))))
+                              AND (
+                                    @createdBy IS NULL
+                                    OR CreatedBy = @createdBy
+                                    OR CreatedBy IS NULL
+                              )
+                            ORDER BY BorrowDate ASC, CreatedDate ASC, BorrowId ASC
+                        `);
+
+                    for (const borrowRow of (borrowRowsResult.recordset || [])) {
+                        if (remainingToLink <= 0) {
+                            break;
+                        }
+
+                        const borrowRequestId = Number(borrowRow.BorrowId);
+                        const originalQuantity = parseNonNegativeInteger(borrowRow.BorrowQuantity, 0);
+                        const alreadyReturned = parseNonNegativeInteger(borrowRow.ReturnedQuantity, 0);
+                        const availableToReturn = Math.max(originalQuantity - alreadyReturned, 0);
+                        const linkedQuantity = Math.min(availableToReturn, remainingToLink);
+
+                        if (!Number.isInteger(borrowRequestId) || borrowRequestId <= 0 || linkedQuantity <= 0) {
+                            continue;
+                        }
+
+                        await new sql.Request(transaction)
+                            .input('borrowId', sql.Int, borrowRequestId)
+                            .input('returnId', sql.Int, borrowId)
+                            .input('quantity', sql.Int, linkedQuantity)
+                            .query(`
+                                IF NOT EXISTS (
+                                    SELECT 1
+                                    FROM AssetBorrowRequestLinks
+                                    WHERE BorrowId = @borrowId
+                                      AND ReturnId = @returnId
+                                )
+                                INSERT INTO AssetBorrowRequestLinks (BorrowId, ReturnId, Quantity)
+                                VALUES (@borrowId, @returnId, @quantity);
+                            `);
+
+                        await new sql.Request(transaction)
+                            .input('borrowId', sql.Int, borrowRequestId)
+                            .input('quantity', sql.Int, linkedQuantity)
+                            .query(`
+                                UPDATE AssetBorrowRequests
+                                SET ReturnedQuantity = CASE
+                                        WHEN ISNULL(ReturnedQuantity, 0) + @quantity > ISNULL(BorrowQuantity, 0)
+                                            THEN ISNULL(BorrowQuantity, 0)
+                                        ELSE ISNULL(ReturnedQuantity, 0) + @quantity
+                                    END,
+                                    RequestStatus = CASE
+                                        WHEN ISNULL(ReturnedQuantity, 0) + @quantity >= ISNULL(BorrowQuantity, 0)
+                                            THEN 'returned'
+                                        ELSE RequestStatus
+                                    END,
+                                    UpdatedDate = GETDATE()
+                                WHERE BorrowId = @borrowId
+                            `);
+
+                        remainingToLink -= linkedQuantity;
+                    }
+                }
             }
         }
 
@@ -4029,6 +4566,8 @@ app.post('/api/asset-borrows/:id/process', requireAssetOrAdmin, async (req, res)
 });
 
 app.delete('/api/asset-borrows/:id', async (req, res) => {
+    const transaction = new sql.Transaction(pool);
+
     try {
         const requesterRole = normalizeRole(req.headers['x-user-role'] || req.query.userRole);
         const requesterId = getUserIdFromRequest(req);
@@ -4043,35 +4582,26 @@ app.delete('/api/asset-borrows/:id', async (req, res) => {
             return res.status(401).json({ success: false, message: 'Yeu cau xac thuc nguoi dung' });
         }
 
-        const deleteResult = await pool.request()
+        await transaction.begin();
+
+        const targetResult = await new sql.Request(transaction)
             .input('borrowId', sql.Int, borrowId)
             .input('requesterId', sql.Int, requesterId || -1)
             .query(`
-                DELETE FROM AssetBorrowRequests
-                OUTPUT DELETED.BorrowId
+                SELECT TOP 1 BorrowId, RequestStatus, CreatedBy
+                FROM AssetBorrowRequests WITH (UPDLOCK, HOLDLOCK)
                 WHERE BorrowId = @borrowId
-                  AND LOWER(LTRIM(RTRIM(ISNULL(RequestStatus, '')))) = 'pending'
                   ${canManageRequests ? '' : 'AND CreatedBy = @requesterId'}
             `);
 
-        if (Array.isArray(deleteResult.recordset) && deleteResult.recordset.length > 0) {
-            return res.json({ success: true, message: 'Da huy don cho' });
-        }
-
-        const existed = await pool.request()
-            .input('borrowId', sql.Int, borrowId)
-            .query(`
-                SELECT TOP 1 BorrowId, RequestStatus, CreatedBy
-                FROM AssetBorrowRequests
-                WHERE BorrowId = @borrowId
-            `);
-
-        const row = existed.recordset?.[0];
+        const row = targetResult.recordset?.[0];
         if (!row) {
+            await transaction.rollback();
             return res.status(404).json({ success: false, message: 'Khong tim thay don can xoa' });
         }
 
         if (!canManageRequests && Number(row.CreatedBy) !== requesterId) {
+            await transaction.rollback();
             return res.status(403).json({
                 success: false,
                 message: 'Ban chi duoc huy don do chinh minh tao'
@@ -4080,17 +4610,37 @@ app.delete('/api/asset-borrows/:id', async (req, res) => {
 
         const currentStatus = normalizeAssetRequestStatus(row.RequestStatus);
         if (currentStatus !== 'pending') {
+            await transaction.rollback();
             return res.status(400).json({
                 success: false,
                 message: 'Chi duoc huy don o trang thai cho xu ly'
             });
         }
 
-        return res.status(400).json({
-            success: false,
-            message: 'Khong the huy don vao luc nay'
-        });
+        await new sql.Request(transaction)
+            .input('borrowId', sql.Int, borrowId)
+            .query(`
+                DELETE FROM AssetBorrowRequestLinks
+                WHERE BorrowId = @borrowId
+                   OR ReturnId = @borrowId
+            `);
+
+        await new sql.Request(transaction)
+            .input('borrowId', sql.Int, borrowId)
+            .query(`
+                DELETE FROM AssetBorrowRequests
+                WHERE BorrowId = @borrowId
+            `);
+
+        await transaction.commit();
+
+        return res.json({ success: true, message: 'Da huy don cho' });
     } catch (err) {
+        try {
+            await transaction.rollback();
+        } catch (rollbackErr) {
+            // Ignore rollback errors when transaction already finished.
+        }
         return res.status(500).json({ success: false, message: err.message });
     }
 });
@@ -4593,13 +5143,45 @@ app.put('/api/assets/:id', requireAssetOrAdmin, async (req, res) => {
 });
 
 app.delete('/api/assets/:id', requireAssetOrAdmin, async (req, res) => {
+    const transaction = new sql.Transaction(pool);
+
     try {
-        await pool.request()
-            .input('assetId', sql.Int, req.params.id)
-            .query('DELETE FROM AssetInventory WHERE AssetId = @assetId');
+        const assetId = Number(req.params.id);
+        if (!Number.isInteger(assetId) || assetId <= 0) {
+            return res.status(400).json({ success: false, message: 'Asset id is invalid' });
+        }
+
+        await transaction.begin();
+
+        await new sql.Request(transaction)
+            .input('assetId', sql.Int, assetId)
+            .query(`
+                DELETE links
+                FROM AssetBorrowRequestLinks links
+                INNER JOIN AssetBorrowRequests requests
+                    ON requests.BorrowId = links.BorrowId
+                    OR requests.BorrowId = links.ReturnId
+                WHERE requests.AssetId = @assetId
+            `);
+
+        const deleteResult = await new sql.Request(transaction)
+            .input('assetId', sql.Int, assetId)
+            .query('DELETE FROM AssetInventory OUTPUT DELETED.AssetId WHERE AssetId = @assetId');
+
+        if (!deleteResult.recordset?.length) {
+            await transaction.rollback();
+            return res.status(404).json({ success: false, message: 'Asset not found' });
+        }
+
+        await transaction.commit();
 
         res.json({ success: true, message: 'Asset deleted' });
     } catch (err) {
+        try {
+            await transaction.rollback();
+        } catch (rollbackErr) {
+            // Ignore rollback errors when transaction already finished.
+        }
         res.status(500).json({ success: false, message: err.message });
     }
 });

database/setup.sql

@@ -222,6 +222,7 @@ BEGIN
         RequestStatus NVARCHAR(20) NOT NULL DEFAULT 'pending',
         BorrowerName NVARCHAR(100) NOT NULL,
         BorrowQuantity INT NOT NULL DEFAULT 1,
+        ReturnedQuantity INT NOT NULL DEFAULT 0,
         Unit NVARCHAR(50),
         BorrowDate DATE NOT NULL DEFAULT CAST(GETDATE() AS DATE),
         RequestNote NVARCHAR(500) NULL,
@@ -264,6 +265,11 @@ BEGIN
     ALTER TABLE AssetBorrowRequests ADD RequestStatus NVARCHAR(20) NOT NULL CONSTRAINT DF_AssetBorrowRequests_RequestStatus DEFAULT('approved');
 END
 
+IF COL_LENGTH('dbo.AssetBorrowRequests', 'ReturnedQuantity') IS NULL
+BEGIN
+    ALTER TABLE AssetBorrowRequests ADD ReturnedQuantity INT NOT NULL CONSTRAINT DF_AssetBorrowRequests_ReturnedQuantity DEFAULT(0);
+END
+
 IF COL_LENGTH('dbo.AssetBorrowRequests', 'RequestNote') IS NULL
 BEGIN
     ALTER TABLE AssetBorrowRequests ADD RequestNote NVARCHAR(500) NULL;
@@ -302,6 +308,83 @@ SET RequestType = ISNULL(NULLIF(LTRIM(RTRIM(RequestType)), ''), 'borrow');
 UPDATE AssetBorrowRequests
 SET RequestStatus = ISNULL(NULLIF(LTRIM(RTRIM(RequestStatus)), ''), 'approved');
 
+UPDATE AssetBorrowRequests
+SET ReturnedQuantity = 0
+WHERE ReturnedQuantity IS NULL OR ReturnedQuantity < 0;
+
+IF NOT EXISTS (SELECT * FROM sys.tables WHERE name = 'AssetBorrowRequestLinks')
+BEGIN
+    CREATE TABLE AssetBorrowRequestLinks (
+        LinkId INT PRIMARY KEY IDENTITY(1,1),
+        BorrowId INT NOT NULL,
+        ReturnId INT NOT NULL,
+        Quantity INT NOT NULL CONSTRAINT DF_AssetBorrowRequestLinks_Quantity DEFAULT(1),
+        CreatedDate DATETIME NOT NULL CONSTRAINT DF_AssetBorrowRequestLinks_CreatedDate DEFAULT(GETDATE()),
+        FOREIGN KEY (BorrowId) REFERENCES AssetBorrowRequests(BorrowId) ON DELETE NO ACTION,
+        FOREIGN KEY (ReturnId) REFERENCES AssetBorrowRequests(BorrowId) ON DELETE NO ACTION
+    );
+END
+
+IF OBJECT_ID('dbo.AssetBorrowRequestLinks', 'U') IS NOT NULL
+BEGIN
+    INSERT INTO AssetBorrowRequestLinks (BorrowId, ReturnId, Quantity)
+    SELECT matchedBorrow.BorrowId,
+           ret.BorrowId,
+           CASE
+               WHEN ISNULL(ret.BorrowQuantity, 0) <= 0 THEN 1
+               WHEN ISNULL(ret.BorrowQuantity, 0) > ISNULL(matchedBorrow.BorrowQuantity, 0) THEN ISNULL(matchedBorrow.BorrowQuantity, 0)
+               ELSE ISNULL(ret.BorrowQuantity, 0)
+           END
+    FROM AssetBorrowRequests ret
+    CROSS APPLY (
+        SELECT TOP 1 b.BorrowId, b.BorrowQuantity
+        FROM AssetBorrowRequests b
+        WHERE LOWER(LTRIM(RTRIM(ISNULL(b.RequestType, '')))) = 'borrow'
+          AND LOWER(LTRIM(RTRIM(ISNULL(b.RequestStatus, '')))) IN ('approved', 'returned')
+          AND b.AssetId = ret.AssetId
+          AND (
+                (ret.CreatedBy IS NOT NULL AND b.CreatedBy = ret.CreatedBy)
+                OR LOWER(LTRIM(RTRIM(ISNULL(b.BorrowerName, '')))) = LOWER(LTRIM(RTRIM(ISNULL(ret.BorrowerName, ''))))
+          )
+          AND b.BorrowDate <= ret.BorrowDate
+        ORDER BY b.BorrowDate DESC, b.CreatedDate DESC, b.BorrowId DESC
+    ) matchedBorrow
+    WHERE LOWER(LTRIM(RTRIM(ISNULL(ret.RequestType, '')))) = 'return'
+      AND LOWER(LTRIM(RTRIM(ISNULL(ret.RequestStatus, '')))) IN ('pending', 'approved')
+      AND NOT EXISTS (
+            SELECT 1
+            FROM AssetBorrowRequestLinks existed
+            WHERE existed.ReturnId = ret.BorrowId
+      )
+      AND NOT EXISTS (
+            SELECT 1
+            FROM AssetBorrowRequestLinks duplicateLink
+            WHERE duplicateLink.ReturnId = ret.BorrowId
+              AND duplicateLink.BorrowId = matchedBorrow.BorrowId
+      );
+
+    UPDATE borrowRows
+    SET ReturnedQuantity = CASE
+            WHEN summary.ReturnedQuantity > ISNULL(borrowRows.BorrowQuantity, 0) THEN ISNULL(borrowRows.BorrowQuantity, 0)
+            ELSE summary.ReturnedQuantity
+        END,
+        RequestStatus = CASE
+            WHEN summary.ReturnedQuantity >= ISNULL(borrowRows.BorrowQuantity, 0)
+                THEN 'returned'
+            ELSE borrowRows.RequestStatus
+        END,
+        UpdatedDate = GETDATE()
+    FROM AssetBorrowRequests borrowRows
+    INNER JOIN (
+        SELECT links.BorrowId, SUM(ISNULL(links.Quantity, 0)) AS ReturnedQuantity
+        FROM AssetBorrowRequestLinks links
+        INNER JOIN AssetBorrowRequests returns ON returns.BorrowId = links.ReturnId
+        WHERE LOWER(LTRIM(RTRIM(ISNULL(returns.RequestStatus, '')))) = 'approved'
+        GROUP BY links.BorrowId
+    ) summary ON summary.BorrowId = borrowRows.BorrowId
+    WHERE LOWER(LTRIM(RTRIM(ISNULL(borrowRows.RequestType, '')))) = 'borrow';
+END
+
 -- ===========================================
 -- 8. CREATE ASSET EXPORT HISTORY TABLE
 -- ===========================================
@@ -482,6 +565,21 @@ BEGIN
     CREATE INDEX IX_AssetBorrowRequests_RequestType ON AssetBorrowRequests(RequestType);
 END
 
+IF NOT EXISTS (SELECT * FROM sys.indexes WHERE name = 'IX_AssetBorrowRequestLinks_BorrowId')
+BEGIN
+    CREATE INDEX IX_AssetBorrowRequestLinks_BorrowId ON AssetBorrowRequestLinks(BorrowId);
+END
+
+IF NOT EXISTS (SELECT * FROM sys.indexes WHERE name = 'IX_AssetBorrowRequestLinks_ReturnId')
+BEGIN
+    CREATE INDEX IX_AssetBorrowRequestLinks_ReturnId ON AssetBorrowRequestLinks(ReturnId);
+END
+
+IF NOT EXISTS (SELECT * FROM sys.indexes WHERE name = 'UX_AssetBorrowRequestLinks_BorrowReturn')
+BEGIN
+    CREATE UNIQUE INDEX UX_AssetBorrowRequestLinks_BorrowReturn ON AssetBorrowRequestLinks(BorrowId, ReturnId);
+END
+
 IF NOT EXISTS (SELECT * FROM sys.indexes WHERE name = 'IX_AssetExportHistory_AssetId')
 BEGIN
     CREATE INDEX IX_AssetExportHistory_AssetId ON AssetExportHistory(AssetId);

public/js/app.js

@@ -1477,6 +1477,12 @@ class AccountManager {
 
         return rows.filter(item => {
             const requestType = this.normalizeAssetRequestType(item.RequestType);
+            const requestStatus = this.normalizeAssetRequestStatus(item.RequestStatus);
+            const relatedReturnCount = this.parseNonNegativeInteger(item?.RelatedReturnCount, 0);
+            if (requestType === 'borrow' && (requestStatus === 'returned' || relatedReturnCount > 0 || this.hasActiveReturnForBorrowRequest(item, rows))) {
+                return false;
+            }
+
             const matchesType = !typeFilter || requestType === typeFilter;
             if (!matchesType) {
                 return false;
@@ -1491,9 +1497,11 @@ class AccountManager {
                 item.AssetCode,
                 item.AssetName,
                 this.getAssetRequestTypeMeta(item.RequestType).label,
-                this.getAssetRequestStatusMeta(item.RequestStatus).label,
+                this.getAssetRequestStatusMeta(item.RequestStatus, item).label,
                 item.Unit,
                 item.BorrowQuantity,
+                item.ReturnedQuantity,
+                item.RemainingQuantity,
                 item.BorrowDate,
                 item.RequestNote,
                 item.RejectReason
@@ -1503,6 +1511,56 @@ class AccountManager {
         });
     }
 
+    hasActiveReturnForBorrowRequest(borrowRequest, rows = []) {
+        const assetId = Number(borrowRequest?.AssetId);
+        const borrowerName = String(borrowRequest?.BorrowerName || '').trim().toLowerCase();
+        const createdBy = Number(borrowRequest?.CreatedBy);
+        const borrowDate = new Date(borrowRequest?.BorrowDate || 0);
+        const borrowTime = Number.isNaN(borrowDate.getTime()) ? null : borrowDate.getTime();
+
+        if (!Number.isFinite(assetId) || assetId <= 0) {
+            return false;
+        }
+
+        return (Array.isArray(rows) ? rows : []).some(candidate => {
+            if (!candidate || candidate === borrowRequest) {
+                return false;
+            }
+
+            if (this.normalizeAssetRequestType(candidate?.RequestType) !== 'return') {
+                return false;
+            }
+
+            const status = this.normalizeAssetRequestStatus(candidate?.RequestStatus);
+            if (status !== 'pending' && status !== 'approved') {
+                return false;
+            }
+
+            if (Number(candidate?.AssetId) !== assetId) {
+                return false;
+            }
+
+            const candidateCreatedBy = Number(candidate?.CreatedBy);
+            const sameCreator = Number.isFinite(createdBy)
+                && Number.isFinite(candidateCreatedBy)
+                && createdBy === candidateCreatedBy;
+            const sameBorrower = borrowerName
+                && String(candidate?.BorrowerName || '').trim().toLowerCase() === borrowerName;
+
+            if (!sameCreator && !sameBorrower) {
+                return false;
+            }
+
+            if (borrowTime === null) {
+                return true;
+            }
+
+            const returnDate = new Date(candidate?.BorrowDate || 0);
+            const returnTime = Number.isNaN(returnDate.getTime()) ? null : returnDate.getTime();
+            return returnTime === null || returnTime >= borrowTime;
+        });
+    }
+
     syncSelectedAssetIds() {
         if (!(this.selectedAssetIds instanceof Set)) {
             this.selectedAssetIds = new Set();
@@ -1919,6 +1977,7 @@ class AccountManager {
     normalizeAssetRequestStatus(value) {
         const normalized = String(value || '').trim().toLowerCase();
         if (normalized === 'approved') return 'approved';
+        if (normalized === 'returned') return 'returned';
         if (normalized === 'rejected') return 'rejected';
         return 'pending';
     }
@@ -1940,12 +1999,23 @@ class AccountManager {
         };
     }
 
-    getAssetRequestStatusMeta(value) {
+    getAssetRequestStatusMeta(value, item = null) {
         const status = this.normalizeAssetRequestStatus(value);
+        const requestType = item ? this.normalizeAssetRequestType(item?.RequestType) : '';
+        const borrowQuantity = this.parseNonNegativeInteger(item?.BorrowQuantity, 0);
+        const returnedQuantity = this.parseNonNegativeInteger(item?.ReturnedQuantity, 0);
+        if (status === 'returned' || (requestType === 'borrow' && status === 'approved' && borrowQuantity > 0 && returnedQuantity >= borrowQuantity)) {
+            return {
+                value: 'returned',
+                label: 'Đã trả',
+                className: 'bg-slate-100 text-slate-700 border border-slate-200'
+            };
+        }
+
         if (status === 'approved') {
             return {
                 value: 'approved',
-                label: 'Chấp nhận',
+                label: requestType === 'borrow' ? 'Đang mượn' : (requestType === 'return' ? 'Đã trả' : 'Chấp nhận'),
                 className: 'bg-green-100 text-green-700 border border-green-200'
             };
         }
@@ -2939,11 +3009,28 @@ class AccountManager {
         const assetName = item.AssetName || '-';
         const assetCode = item.AssetCode ? `<div class="text-[11px] text-slate-500">${this.escapeHtml(item.AssetCode)}</div>` : '';
         const typeMeta = this.getAssetRequestTypeMeta(item.RequestType);
-        const statusMeta = this.getAssetRequestStatusMeta(item.RequestStatus);
+        const statusMeta = this.getAssetRequestStatusMeta(item.RequestStatus, item);
         const note = String(item?.RequestNote || '').trim();
         const rejectReason = String(item?.RejectReason || '').trim();
         const canCancel = this.canCurrentUserCancelAssetRequest(item);
         const requestId = Number(item?.BorrowId) || 0;
+        const requestType = this.normalizeAssetRequestType(item?.RequestType);
+        const returnedQuantity = this.parseNonNegativeInteger(item?.ReturnedQuantity, 0);
+        const borrowQuantity = this.parseNonNegativeInteger(item?.BorrowQuantity, 0);
+        const remainingQuantity = this.parseNonNegativeInteger(item?.RemainingQuantity, Math.max(borrowQuantity - returnedQuantity, 0));
+        const returnProgressHtml = requestType === 'borrow' && returnedQuantity > 0 && statusMeta.value !== 'returned'
+            ? `<div class="mt-1 text-[11px] text-slate-500 whitespace-nowrap">Đã trả ${returnedQuantity}/${borrowQuantity}, còn ${remainingQuantity}</div>`
+            : '';
+        const detailActionHtml = `
+            <button
+                class="asset-borrow-detail-btn inline-flex h-8 w-8 items-center justify-center rounded-md border border-slate-200 text-slate-500 hover:bg-slate-50 hover:text-primary transition-colors"
+                data-request-id="${requestId}"
+                title="Xem chi tiết"
+                aria-label="Xem chi tiết đơn"
+            >
+                <span class="material-symbols-outlined text-base">info</span>
+            </button>
+        `;
         const cancelActionHtml = canCancel
             ? `<button class="asset-borrow-cancel-btn px-3 py-1.5 rounded-md bg-red-600 hover:bg-red-700 text-white text-xs font-bold whitespace-nowrap" data-request-id="${requestId}">Hủy đơn</button>`
             : `<span class="text-xs text-slate-400">-</span>`;
@@ -2956,17 +3043,19 @@ class AccountManager {
                     <div>${this.escapeHtml(assetName)}</div>
                     ${assetCode}
                 </td>
-                <td class="px-4 py-3 text-sm text-slate-600">
-                    <span class="inline-flex items-center px-2 py-1 rounded-md text-xs font-bold ${typeMeta.className}">${typeMeta.label}</span>
+                <td class="px-4 py-3 text-sm text-slate-600 whitespace-nowrap">
+                    <span class="inline-flex items-center px-2 py-1 rounded-md text-xs font-bold whitespace-nowrap ${typeMeta.className}">${typeMeta.label}</span>
                 </td>
                 <td class="px-4 py-3 text-sm text-slate-600">
                     <span class="inline-flex items-center px-2 py-1 rounded-md text-xs font-bold ${statusMeta.className}">${statusMeta.label}</span>
+                    ${returnProgressHtml}
                 </td>
                 <td class="px-4 py-3 text-sm text-slate-600">${this.escapeHtml(item.Unit || '-')}</td>
                 <td class="px-4 py-3 text-sm text-slate-600">${Number(item.BorrowQuantity) || 0}</td>
                 <td class="px-4 py-3 text-sm text-slate-600 whitespace-nowrap">${this.formatDateOnly(item.BorrowDate)}</td>
                 <td class="px-4 py-3 text-sm text-slate-600 max-w-xs">${this.escapeHtml(note || '-')}</td>
                 <td class="px-4 py-3 text-sm text-slate-600 max-w-xs">${this.escapeHtml(rejectReason || '-')}</td>
+                <td class="px-4 py-3 text-sm text-slate-600 text-center">${detailActionHtml}</td>
                 <td class="px-4 py-3 text-sm text-slate-600">${cancelActionHtml}</td>
             </tr>
         `;
@@ -2993,7 +3082,7 @@ class AccountManager {
     buildAssetBorrowEmptyRowHtml() {
         return `
             <tr>
-                <td colspan="11" class="px-4 py-8 text-sm text-center text-slate-500">Chưa có đơn mượn/trả tài sản nào.</td>
+                <td colspan="12" class="px-4 py-8 text-sm text-center text-slate-500">Chưa có đơn mượn/trả tài sản nào.</td>
             </tr>
         `;
     }
@@ -3058,7 +3147,7 @@ class AccountManager {
 
                 <div class="flex-1 bg-white rounded-xl border border-slate-200 shadow-sm flex flex-col overflow-hidden min-h-0">
                     <div class="table-wrap overflow-y-auto overflow-x-auto flex-1">
-                        <table class="w-full text-left border-collapse">
+                        <table class="w-full text-left border-collapse" style="min-width: 1500px;">
                             <thead class="sticky top-0 z-10 bg-slate-50 border-b border-slate-200">
                                 <tr>
                                     <th class="px-4 py-2.5 text-[10px] font-bold uppercase tracking-wider text-slate-500">STT</th>
@@ -3255,13 +3344,14 @@ class AccountManager {
                                     <th class="px-4 py-2.5 text-[10px] font-bold uppercase tracking-wider text-slate-500">STT</th>
                                     <th class="px-4 py-2.5 text-[10px] font-bold uppercase tracking-wider text-slate-500">Tên đầy đủ</th>
                                     <th class="px-4 py-2.5 text-[10px] font-bold uppercase tracking-wider text-slate-500">Tài sản</th>
-                                    <th class="px-4 py-2.5 text-[10px] font-bold uppercase tracking-wider text-slate-500">Danh mục</th>
+                                    <th class="px-4 py-2.5 text-[10px] font-bold uppercase tracking-wider text-slate-500 whitespace-nowrap">Danh mục</th>
                                     <th class="px-4 py-2.5 text-[10px] font-bold uppercase tracking-wider text-slate-500">Trạng thái</th>
                                     <th class="px-4 py-2.5 text-[10px] font-bold uppercase tracking-wider text-slate-500">Đơn vị</th>
                                     <th class="px-4 py-2.5 text-[10px] font-bold uppercase tracking-wider text-slate-500">Số lượng</th>
                                     <th class="px-4 py-2.5 text-[10px] font-bold uppercase tracking-wider text-slate-500">Ngày</th>
                                     <th class="px-4 py-2.5 text-[10px] font-bold uppercase tracking-wider text-slate-500">Ghi chú</th>
                                     <th class="px-4 py-2.5 text-[10px] font-bold uppercase tracking-wider text-slate-500">Lý do</th>
+                                    <th class="px-4 py-2.5 text-[10px] font-bold uppercase tracking-wider text-slate-500 text-center">Chi tiết</th>
                                     <th class="px-4 py-2.5 text-[10px] font-bold uppercase tracking-wider text-slate-500">Hành động</th>
                                 </tr>
                             </thead>
@@ -3304,6 +3394,134 @@ class AccountManager {
         this.setupAssetBorrowPagerListeners();
         this.updatePendingAssetRequestsBadge();
     }
+
+    async openAssetBorrowDetailsModal(requestId) {
+        try {
+            const response = await fetch(`${this.apiBase}/asset-borrows/${requestId}/history`, {
+                headers: this.getAuthHeaders(false)
+            });
+            const data = await response.json();
+
+            if (!response.ok || !data.success) {
+                this.notifyFailure(data.message || 'Không tải được chi tiết đơn.');
+                return;
+            }
+
+            this.showAssetBorrowDetailsModal(data.data || {});
+        } catch (err) {
+            console.error(err);
+            this.notifyFailure('Không tải được chi tiết đơn.');
+        }
+    }
+
+    buildAssetBorrowDetailCardHtml(item) {
+        const typeMeta = this.getAssetRequestTypeMeta(item?.RequestType);
+        const statusMeta = this.getAssetRequestStatusMeta(item?.RequestStatus, item);
+        const requestType = this.normalizeAssetRequestType(item?.RequestType);
+        const dateLabel = requestType === 'return' ? 'Ngày trả' : 'Ngày mượn';
+        const assetName = `${item?.AssetCode ? `${item.AssetCode} - ` : ''}${item?.AssetName || '-'}`;
+        const note = String(item?.RequestNote || '').trim();
+        const rejectReason = String(item?.RejectReason || '').trim();
+        const returnedQuantity = this.parseNonNegativeInteger(item?.ReturnedQuantity, 0);
+        const borrowQuantity = this.parseNonNegativeInteger(item?.BorrowQuantity, 0);
+        const remainingQuantity = this.parseNonNegativeInteger(item?.RemainingQuantity, Math.max(borrowQuantity - returnedQuantity, 0));
+        const returnSummary = requestType === 'borrow' && returnedQuantity > 0
+            ? `<div><span class="font-bold">Đã trả:</span> ${returnedQuantity}/${borrowQuantity}${remainingQuantity > 0 ? `, còn ${remainingQuantity}` : ''}</div>`
+            : '';
+
+        return `
+            <div class="w-full min-w-0 overflow-hidden rounded-lg border border-slate-200 bg-white p-4 text-sm text-slate-700 space-y-2 break-words">
+                <div class="flex flex-wrap items-center gap-2 min-w-0">
+                    <span class="inline-flex items-center px-2 py-1 rounded-md text-xs font-bold ${typeMeta.className}">${typeMeta.label}</span>
+                    <span class="inline-flex items-center px-2 py-1 rounded-md text-xs font-bold ${statusMeta.className}">${statusMeta.label}</span>
+                    <span class="ml-auto text-xs font-extrabold text-slate-500">#${Number(item?.BorrowId) || '-'}</span>
+                </div>
+                <div class="grid grid-cols-1 md:grid-cols-2 gap-x-4 gap-y-1 min-w-0">
+                    <div class="min-w-0"><span class="font-bold">Người tạo:</span> ${this.escapeHtml(item?.BorrowerName || '-')}</div>
+                    <div class="min-w-0"><span class="font-bold">${dateLabel}:</span> ${this.formatDateOnly(item?.BorrowDate)}</div>
+                    <div class="md:col-span-2 min-w-0"><span class="font-bold">Tài sản:</span> ${this.escapeHtml(assetName)}</div>
+                    <div class="min-w-0"><span class="font-bold">Số lượng:</span> ${Number(item?.BorrowQuantity) || 0}</div>
+                    <div class="min-w-0"><span class="font-bold">Đơn vị:</span> ${this.escapeHtml(item?.Unit || '-')}</div>
+                    ${returnSummary}
+                    <div class="min-w-0"><span class="font-bold">Ngày xử lý:</span> ${this.formatDateTime(item?.ProcessedDate)}</div>
+                    <div class="min-w-0"><span class="font-bold">Người xử lý:</span> ${this.escapeHtml(item?.ProcessedByName || '-')}</div>
+                    <div class="md:col-span-2 min-w-0"><span class="font-bold">Ghi chú:</span> ${this.escapeHtml(note || '-')}</div>
+                    <div class="md:col-span-2 min-w-0"><span class="font-bold">Lý do:</span> ${this.escapeHtml(rejectReason || '-')}</div>
+                </div>
+            </div>
+        `;
+    }
+
+    showAssetBorrowDetailsModal(history) {
+        const selected = history?.request || {};
+        const borrowRequests = Array.isArray(history?.borrowRequests) ? history.borrowRequests : [];
+        const returnRequests = Array.isArray(history?.returnRequests) ? history.returnRequests : [];
+        const selectedTypeMeta = this.getAssetRequestTypeMeta(selected?.RequestType);
+        const selectedStatusMeta = this.getAssetRequestStatusMeta(selected?.RequestStatus, selected);
+        const assetName = `${selected?.AssetCode ? `${selected.AssetCode} - ` : ''}${selected?.AssetName || '-'}`;
+
+        const renderList = (items, emptyText) => items.length
+            ? items.map(item => this.buildAssetBorrowDetailCardHtml(item)).join('')
+            : `<div class="rounded-lg border border-dashed border-slate-300 px-4 py-8 text-sm text-center text-slate-500">${emptyText}</div>`;
+
+        let container = document.getElementById('assetBorrowDetailsModalContainer');
+        if (!container) {
+            container = document.createElement('div');
+            container.id = 'assetBorrowDetailsModalContainer';
+            document.body.appendChild(container);
+        }
+
+        container.innerHTML = `
+            <div class="fixed inset-0 bg-black/40 backdrop-blur-sm modal-backdrop open" id="assetBorrowDetailsModal" style="z-index:1000;display:flex;align-items:center;justify-content:center;padding:16px;overflow:hidden;">
+                <div class="modal-content bg-white rounded-xl shadow-2xl border border-slate-200 overflow-hidden flex flex-col" style="position:relative;z-index:1001;width:min(1080px, calc(100vw - 32px));max-height:calc(100vh - 32px);box-sizing:border-box;">
+                    <div class="px-6 py-4 border-b border-slate-100 flex items-center justify-between gap-3 bg-slate-50">
+                        <div class="min-w-0">
+                            <h3 class="text-base font-extrabold text-slate-900">Chi tiết mượn/trả tài sản</h3>
+                            <div class="mt-1 flex flex-wrap items-center gap-2 text-xs text-slate-500 min-w-0">
+                                <span class="font-bold text-slate-700 break-words min-w-0">${this.escapeHtml(assetName)}</span>
+                                <span class="inline-flex items-center px-2 py-0.5 rounded ${selectedTypeMeta.className}">${selectedTypeMeta.label}</span>
+                                <span class="inline-flex items-center px-2 py-0.5 rounded ${selectedStatusMeta.className}">${selectedStatusMeta.label}</span>
+                            </div>
+                        </div>
+                        <button class="p-1.5 rounded-lg hover:bg-slate-200 text-slate-400 transition-colors" onclick="closeAssetBorrowDetailsModal()" title="Đóng">
+                            <span class="material-symbols-outlined">close</span>
+                        </button>
+                    </div>
+                    <div class="p-4 md:p-6 overflow-y-auto overflow-x-hidden bg-slate-50/60">
+                        <div class="grid grid-cols-1 lg:grid-cols-2 gap-4 min-w-0">
+                            <section class="space-y-3 min-w-0">
+                                <div class="flex items-center justify-between">
+                                    <h4 class="text-sm font-extrabold text-blue-700">Lịch sử đơn mượn</h4>
+                                    <span class="text-xs font-bold text-slate-500">${borrowRequests.length}</span>
+                                </div>
+                                ${renderList(borrowRequests, 'Không tìm thấy đơn mượn liên quan.')}
+                            </section>
+                            <section class="space-y-3 min-w-0">
+                                <div class="flex items-center justify-between">
+                                    <h4 class="text-sm font-extrabold text-emerald-700">Lịch sử đơn trả</h4>
+                                    <span class="text-xs font-bold text-slate-500">${returnRequests.length}</span>
+                                </div>
+                                ${renderList(returnRequests, 'Chưa có đơn trả liên quan.')}
+                            </section>
+                        </div>
+                    </div>
+                    <div class="p-4 border-t border-slate-100 bg-white flex justify-end">
+                        <button type="button" class="px-4 py-2 text-xs font-bold text-slate-600 border border-slate-200 rounded-lg hover:bg-slate-50" onclick="closeAssetBorrowDetailsModal()">Đóng</button>
+                    </div>
+                </div>
+            </div>
+        `;
+
+        const modal = document.getElementById('assetBorrowDetailsModal');
+        if (modal) {
+            modal.addEventListener('click', event => {
+                if (event.target === modal) {
+                    closeAssetBorrowDetailsModal();
+                }
+            });
+        }
+    }
+
     setupAssetBorrowPagerListeners() {
         document.querySelectorAll('.asset-borrow-page-btn').forEach(btn => {
             btn.addEventListener('click', () => {
@@ -3350,6 +3568,15 @@ class AccountManager {
         const tableBody = document.querySelector('.asset-borrows-table-body');
         if (tableBody && tableBody.dataset.boundActions !== 'true') {
             tableBody.addEventListener('click', (event) => {
+                const detailButton = event.target.closest('.asset-borrow-detail-btn');
+                if (detailButton) {
+                    const requestId = Number(detailButton.dataset.requestId);
+                    if (Number.isFinite(requestId) && requestId > 0) {
+                        this.openAssetBorrowDetailsModal(requestId);
+                    }
+                    return;
+                }
+
                 const cancelButton = event.target.closest('.asset-borrow-cancel-btn');
                 if (!cancelButton) {
                     return;
@@ -7523,6 +7750,13 @@ function closeAssetPendingRequestsModal() {
     }
 }
 
+function closeAssetBorrowDetailsModal() {
+    const modal = document.getElementById('assetBorrowDetailsModal');
+    if (modal) {
+        modal.classList.remove('open');
+    }
+}
+
 function closeAssetRequestRejectModal() {
     const modal = document.getElementById('assetRequestRejectModal');
     if (modal) {

public/pages/index.html

@@ -309,6 +309,6 @@
         </div>
     </main>
 
-    <script src="../js/app.js?v=20260424-1"></script>
+    <script src="../js/app.js?v=20260515-4"></script>
 </body>
 </html>