using RobotNet10.CustomConfiguration.Models;
using RobotNet10.CustomConfiguration.Services;

namespace RobotNet10.FleetManager.Services.ConfigManager;

/// <summary>
/// Service implementation for managing ACSTraffic configurations
/// </summary>
public class ACSTrafficConfig : IACSTrafficConfig
{
    private readonly IConfigManager _configManager;
    private readonly Logger<ACSTrafficConfig> _logger;

    private readonly Lock _lockObject = new();
    private bool _configLoaded = false;

    /// <summary>
    /// Event triggered when ACSTraffic configuration is changed/reloaded
    /// </summary>
    public event EventHandler? ConfigChanged;

    private bool _trafficEnable = false;
    private int _trafficInterval = 1000;
    private string _trafficURL = string.Empty;
    private Dictionary<string, string> _acsZoneMaping = [];
    private Dictionary<string, string> _acsOutMaping = [];
    private bool _publishEnable = false;
    private string _publishURL = string.Empty;
    private int _publishInterval = 1000;

    private const string ACS_TRAFFIC_CONFIG_TYPE = "ACSTrafficConfig";

    public ACSTrafficConfig(IConfigManager configManager, Logger<ACSTrafficConfig> logger)
    {
        _configManager = configManager ?? throw new ArgumentNullException(nameof(configManager));
        _logger = logger;
        
        // Subscribe to config changes
        _configManager.ConfigChanged += OnConfigChanged;
    }

    public bool TrafficEnable
    {
        get
        {
            EnsureConfigLoaded();
            return _trafficEnable;
        }
    }

    public int TrafficInterval
    {
        get
        {
            EnsureConfigLoaded();
            return _trafficInterval;
        }
    }

    public string TrafficURL
    {
        get
        {
            EnsureConfigLoaded();
            return _trafficURL;
        }
    }

    public Dictionary<string, string> ACSZoneMaping
    {
        get
        {
            EnsureConfigLoaded();
            return _acsZoneMaping;
        }
    }

    public bool PublishEnable
    {
        get
        {
            EnsureConfigLoaded();
            return _publishEnable;
        }
    }

    public string PublishURL
    {
        get
        {
            EnsureConfigLoaded();
            return _publishURL;
        }
    }

    public int PublishInterval
    {
        get
        {
            EnsureConfigLoaded();
            return _publishInterval;
        }
    }

    public Dictionary<string, string> ACSOutMaping
    {
        get
        {
            EnsureConfigLoaded();
            return _acsOutMaping;
        }
    }

    private void EnsureConfigLoaded()
    {
        if (!_configLoaded)
        {
            lock (_lockObject)
            {
                if (!_configLoaded)
                {
                    LoadACSTrafficConfigAsync().GetAwaiter().GetResult();
                }
            }
        }
    }

    private async Task LoadACSTrafficConfigAsync()
    {
        try
        {
            var configFile = await _configManager.GetConfigByTypeAsync(ACS_TRAFFIC_CONFIG_TYPE);
            
            if (configFile == null)
            {
                _logger.Warning("ACSTraffic configuration not found, using defaults");
                _trafficEnable = false;
                _trafficInterval = 1000;
                _trafficURL = string.Empty;
                _acsZoneMaping = [];
                _acsOutMaping = [];
                _publishEnable = false;
                _publishURL = string.Empty;
                _publishInterval = 1000;
            }
            else
            {
                MapConfigVariablesToProperties(configFile.Variables);
                _logger.Info("ACSTraffic configuration loaded successfully");
            }
        }
        catch (Exception ex)
        {
            _logger.Error($"Error loading ACSTraffic configuration, using defaults: {ex.Message}");
            _trafficEnable = false;
            _trafficInterval = 1000;
            _trafficURL = string.Empty;
            _acsZoneMaping = [];
            _acsOutMaping = [];
            _publishEnable = false;
            _publishURL = string.Empty;
            _publishInterval = 1000;
        }
        finally
        {
            _configLoaded = true;
            // Trigger ConfigChanged event after config is loaded/reloaded
            OnConfigChanged();
        }
    }

    private void OnConfigChanged(object? sender, RobotNet10.CustomConfiguration.Events.ConfigChangedEventArgs e)
    {
        // Reload config if our config type changed
        if (e.ConfigType == ACS_TRAFFIC_CONFIG_TYPE)
        {
            lock (_lockObject)
            {
                _configLoaded = false;
            }
            _logger.Info($"ACSTraffic configuration changed ({e.ConfigType}), will reload on next access");
        }
    }

    /// <summary>
    /// Trigger ConfigChanged event to notify subscribers that config has been reloaded
    /// </summary>
    private void OnConfigChanged()
    {
        ConfigChanged?.Invoke(this, EventArgs.Empty);
    }

    private void MapConfigVariablesToProperties(List<ConfigVariable> variables)
    {
        foreach (var variable in variables)
        {
            if (variable.Value == null)
                continue;

            try
            {
                switch (variable.Name)
                {
                    case nameof(TrafficEnable):
                        _trafficEnable = (bool)ConvertValue(variable.Value, typeof(bool))!;
                        break;
                    case nameof(TrafficInterval):
                        _trafficInterval = (int)ConvertValue(variable.Value, typeof(int))!;
                        break;
                    case nameof(TrafficURL):
                        _trafficURL = (string)ConvertValue(variable.Value, typeof(string))!;
                        break;
                    case nameof(ACSZoneMaping):
                        _acsZoneMaping = (Dictionary<string, string>)ConvertValue(variable.Value, typeof(Dictionary<string, string>))!;
                        break;
                    case nameof(ACSOutMaping):
                        _acsOutMaping = (Dictionary<string, string>)ConvertValue(variable.Value, typeof(Dictionary<string, string>))!;
                        break;
                    case nameof(PublishEnable):
                        _publishEnable = (bool)ConvertValue(variable.Value, typeof(bool))!;
                        break;
                    case nameof(PublishURL):
                        _publishURL = (string)ConvertValue(variable.Value, typeof(string))!;
                        break;
                    case nameof(PublishInterval):
                        _publishInterval = (int)ConvertValue(variable.Value, typeof(int))!;
                        break;
                    default:
                        _logger.Warning($"Unknown variable name: {variable.Name}");
                        break;
                }
            }
            catch (Exception ex)
            {
                _logger.Warning($"Failed to set property {variable.Name} from variable: {ex.Message}");
            }
        }
    }

    private object? ConvertValue(object? value, Type targetType)
    {
        if (value == null)
            return targetType.IsValueType ? Activator.CreateInstance(targetType) : null;

        // If value is already of the correct type, return it
        if (targetType.IsInstanceOfType(value))
            return value;

        try
        {
            // Handle nullable types
            var underlyingType = Nullable.GetUnderlyingType(targetType) ?? targetType;

            // Convert based on target type
            if (underlyingType == typeof(string))
            {
                return value.ToString() ?? string.Empty;
            }
            else if (underlyingType == typeof(int))
            {
                if (value is int i) return i;
                if (int.TryParse(value.ToString(), out var parsed)) return parsed;
                if (value is double d) return (int)d;
                throw new InvalidCastException($"Cannot convert {value.GetType()} to int");
            }
            else if (underlyingType == typeof(double))
            {
                if (value is double d) return d;
                if (double.TryParse(value.ToString(), out var parsed)) return parsed;
                if (value is int i) return i;
                throw new InvalidCastException($"Cannot convert {value.GetType()} to double");
            }
            else if (underlyingType == typeof(bool))
            {
                if (value is bool b) return b;
                if (bool.TryParse(value.ToString(), out var parsed)) return parsed;
                // Handle numeric values: 0/1, "0"/"1", etc.
                if (value.ToString()?.Trim() == "0" || value.ToString()?.Trim().ToLower() == "false") return false;
                if (value.ToString()?.Trim() == "1" || value.ToString()?.Trim().ToLower() == "true") return true;
                throw new InvalidCastException($"Cannot convert {value.GetType()} to bool");
            }
            else if (underlyingType.IsEnum)
            {
                var enumValue = Enum.Parse(underlyingType, value.ToString() ?? "", true);
                return enumValue;
            }
            else if (underlyingType.IsGenericType && underlyingType.GetGenericTypeDefinition() == typeof(Dictionary<,>))
            {
                // Handle Dictionary types - try to parse from JSON string
                return ConvertDictionary(value, underlyingType);
            }
            else
            {
                // Try standard conversion
                return Convert.ChangeType(value, underlyingType);
            }
        }
        catch (Exception ex)
        {
            _logger.Warning($"Error converting value {value} of type {value.GetType()} to {targetType}: {ex.Message}");
            throw;
        }
    }

    /// <summary>
    /// Convert value to Dictionary type (supports Dictionary&lt;string, string&gt;)
    /// </summary>
    private object ConvertDictionary(object value, Type dictionaryType)
    {
        try
        {
            // Get key and value types
            var genericArgs = dictionaryType.GetGenericArguments();
            var keyType = genericArgs[0];
            var valueType = genericArgs[1];

            // If value is already the correct Dictionary type, return it
            if (dictionaryType.IsInstanceOfType(value))
            {
                return value;
            }

            // If value is Dictionary<string, object>, try to convert
            if (value is Dictionary<string, object> stringDict)
            {
                var result = Activator.CreateInstance(dictionaryType);
                var addMethod = dictionaryType.GetMethod("Add");
                
                if (addMethod != null && result != null)
                {
                    foreach (var kvp in stringDict)
                    {
                        var key = ConvertValue(kvp.Key, keyType);
                        var val = ConvertValue(kvp.Value, valueType);
                        addMethod.Invoke(result, [key, val]);
                    }
                    return result;
                }
            }

            // Try parse as JSON string
            var jsonString = value.ToString();
            if (!string.IsNullOrEmpty(jsonString))
            {
                try
                {
                    var doc = System.Text.Json.JsonDocument.Parse(jsonString);
                    if (doc.RootElement.ValueKind == System.Text.Json.JsonValueKind.Object)
                    {
                        var result = Activator.CreateInstance(dictionaryType);
                        var addMethod = dictionaryType.GetMethod("Add");
                        
                        if (addMethod != null && result != null)
                        {
                            foreach (var prop in doc.RootElement.EnumerateObject())
                            {
                                // Convert key
                                var key = ConvertValue(prop.Name, keyType);
                                
                                // Convert value
                                var val = ConvertValue(prop.Value.GetString() ?? prop.Value.GetRawText(), valueType);
                                
                                addMethod.Invoke(result, [key, val]);
                            }
                            return result;
                        }
                    }
                }
                catch (Exception ex)
                {
                    _logger.Warning($"Failed to parse Dictionary from JSON string: {ex.Message}");
                }
            }

            // If all else fails, return default (empty dictionary)
            _logger.Warning($"Cannot convert {value.GetType()} to {dictionaryType}, using default (empty dictionary)");
            return Activator.CreateInstance(dictionaryType) ?? throw new InvalidOperationException($"Cannot create instance of {dictionaryType}");
        }
        catch (Exception ex)
        {
            _logger.Warning($"Error converting Dictionary: {ex.Message}");
            // Return default (empty dictionary)
            return Activator.CreateInstance(dictionaryType) ?? throw new InvalidOperationException($"Cannot create instance of {dictionaryType}");
        }
    }
}