using System;
using XP.Hardware.MotionControl.Abstractions;
using XP.Hardware.MotionControl.Abstractions.Enums;
using XP.Hardware.Plc.Abstractions;

namespace XP.Hardware.MotionControl.Implementations
{
    /// <summary>
    /// 基于 PLC 的直线轴实现 | PLC-based Linear Axis Implementation
    /// 通过 ISignalDataService 与 PLC 通信，信号名称硬编码在 MotionSignalNames 中
    /// Communicates with PLC via ISignalDataService, signal names hardcoded in MotionSignalNames
    /// </summary>
    public class PlcLinearAxis : LinearAxisBase
    {
        private readonly ISignalDataService _signalService;
        private readonly string _readSignal;
        private readonly string _writeSignal;
        private readonly string _speedSignal;
        private readonly string _jogPosSignal;
        private readonly string _jogNegSignal;
        private readonly string _homeSignal;
        private readonly string _stopSignal;
        private readonly string _limitPosSignal;
        private readonly string _limitNegSignal;

        /// <summary>
        /// 构造函数 | Constructor
        /// </summary>
        public PlcLinearAxis(
            AxisId axisId, double min, double max, double origin,
            ISignalDataService signalService,
            string readSignal, string writeSignal, string speedSignal,
            string jogPosSignal, string jogNegSignal,
            string homeSignal, string stopSignal)
            : base(axisId, min, max, origin)
        {
            _signalService = signalService ?? throw new ArgumentNullException(nameof(signalService));
            _readSignal = readSignal;
            _writeSignal = writeSignal;
            _speedSignal = speedSignal;
            _jogPosSignal = jogPosSignal;
            _jogNegSignal = jogNegSignal;
            _homeSignal = homeSignal;
            _stopSignal = stopSignal;
            _limitPosSignal = $"MC_{axisId}_LimitPos";
            _limitNegSignal = $"MC_{axisId}_LimitNeg";
        }

        /// <inheritdoc/>
        public override MotionResult MoveToTarget(double target, double? speed = null)
        {
            if (!ValidateTarget(target))
                return MotionResult.Fail($"目标位置 {target} 超出范围 [{_min}, {_max}]");
            if (Status == AxisStatus.Moving)
                return MotionResult.Fail($"轴 {_axisId} 正在运动中，拒绝重复命令");

            if (speed.HasValue)
                _signalService.EnqueueWrite(_speedSignal, (float)speed.Value);
            _signalService.EnqueueWrite(_writeSignal, (float)target);
            Status = AxisStatus.Moving;
            return MotionResult.Ok();
        }

        /// <inheritdoc/>
        public override MotionResult JogStart(bool positive)
        {
            if (Status == AxisStatus.Homing)
                return MotionResult.Fail($"轴 {_axisId} 正在回零，拒绝 Jog 命令");

            var signal = positive ? _jogPosSignal : _jogNegSignal;
            _signalService.EnqueueWrite(signal, true);
            return MotionResult.Ok();
        }

        /// <inheritdoc/>
        public override MotionResult JogStop()
        {
            _signalService.EnqueueWrite(_jogPosSignal, false);
            _signalService.EnqueueWrite(_jogNegSignal, false);
            return MotionResult.Ok();
        }

        /// <inheritdoc/>
        public override MotionResult Home()
        {
            _signalService.EnqueueWrite(_homeSignal, true);
            Status = AxisStatus.Homing;
            return MotionResult.Ok();
        }

        /// <inheritdoc/>
        public override MotionResult Stop()
        {
            _signalService.EnqueueWrite(_stopSignal, true);
            return MotionResult.Ok();
        }

        /// <inheritdoc/>
        public override void UpdateStatus()
        {
            ActualPosition = _signalService.GetValueByName<float>(_readSignal);
            try { PositiveLimitHit = _signalService.GetValueByName<bool>(_limitPosSignal); } catch { }
            try { NegativeLimitHit = _signalService.GetValueByName<bool>(_limitNegSignal); } catch { }
            if (PositiveLimitHit || NegativeLimitHit) Status = AxisStatus.Alarm;
        }
    }
}