using Sick.SafetyScanners.Helpers;

namespace Sick.SafetyScanners.Cola2.Commands;

/// <summary>
/// Base command for method calls to the sensor
/// Thread-safe implementation
/// </summary>
public abstract class MethodCommand : CommandBase
{
    private readonly ushort _methodIndex;
    
    protected MethodCommand(ushort methodIndex)
        : base(0x4D, 0x49) // 'M' and 'I' in ASCII (Method by Index)
    {
        _methodIndex = methodIndex;
    }
    
    public ushort MethodIndex => _methodIndex;
    
    public override bool CanBeExecutedWithoutSessionId => false;
    
    protected override ReadOnlyMemory<byte> AddTelegramData()
    {
        var data = new byte[2];
        var span = data.AsSpan();
        
        // Method index (2 bytes, little endian)
        ReadWriteHelper.WriteUint16LittleEndian(span, 0, _methodIndex);
        
        return data;
    }
    
    protected override bool ProcessReplyInternal(ReadOnlyMemory<byte> replyData, 
        byte replyCommandType, byte replyCommandMode)
    {
        // Reply should be 'A' (0x41) and 'I' (0x49) for Acknowledge
        if ((replyCommandType == 0x41 && replyCommandMode == 0x49) ||
            (replyCommandType == 'A' && replyCommandMode == 'I'))
        {
            return true;
        }
        
        return false;
    }
}