using OrpaonVision.SiteApp.Runtime.Services;
using System.ComponentModel;
using System.Runtime.CompilerServices;
using System.Windows.Media;

namespace OrpaonVision.SiteApp.ViewModels
{
    /// <summary>
    /// 运行端主窗口 ViewModel。
    /// </summary>
    public sealed class MainWindowViewModel : INotifyPropertyChanged
    {
        private readonly ICameraService _cameraService;
        private readonly IInferenceService _inferenceService;
        private readonly IRuleEngineService _ruleEngineService;
        private readonly IRuntimeStateMachineService _runtimeStateMachineService;

        private string _statusText = "准备就绪。";
        private Brush _statusBrush = Brushes.DarkGreen;
        private string _layerText = "1/1";
        private string _inferenceText = "-";
        private string _decisionText = "-";

        /// <summary>
        /// 构造函数。
        /// </summary>
        public MainWindowViewModel(
            ICameraService cameraService,
            IInferenceService inferenceService,
            IRuleEngineService ruleEngineService,
            IRuntimeStateMachineService runtimeStateMachineService)
        {
            _cameraService = cameraService;
            _inferenceService = inferenceService;
            _ruleEngineService = ruleEngineService;
            _runtimeStateMachineService = runtimeStateMachineService;

            RefreshSnapshot();
        }

        /// <summary>
        /// 状态文本。
        /// </summary>
        public string StatusText
        {
            get => _statusText;
            private set => SetProperty(ref _statusText, value);
        }

        /// <summary>
        /// 状态颜色。
        /// </summary>
        public Brush StatusBrush
        {
            get => _statusBrush;
            private set => SetProperty(ref _statusBrush, value);
        }

        /// <summary>
        /// 当前层显示文本。
        /// </summary>
        public string LayerText
        {
            get => _layerText;
            private set => SetProperty(ref _layerText, value);
        }

        /// <summary>
        /// 最近一次推理结果。
        /// </summary>
        public string InferenceText
        {
            get => _inferenceText;
            private set => SetProperty(ref _inferenceText, value);
        }

        /// <summary>
        /// 最近一次规则判定结果。
        /// </summary>
        public string DecisionText
        {
            get => _decisionText;
            private set => SetProperty(ref _decisionText, value);
        }

        /// <summary>
        /// 执行一轮采集-推理-规则判定。
        /// </summary>
        public void RunOneCycle()
        {
            var snapshot = _runtimeStateMachineService.GetSnapshot();

            var captureResult = _cameraService.CaptureFrame();
            if (!captureResult.Succeeded || captureResult.Data is null)
            {
                SetError("相机采图失败。", captureResult.Message);
                return;
            }

            var predictResult = _inferenceService.Predict(captureResult.Data);
            if (!predictResult.Succeeded || predictResult.Data is null)
            {
                SetError("模型推理失败。", predictResult.Message);
                return;
            }

            var inference = predictResult.Data;
            InferenceText = $"{inference.Label} (置信度: {inference.Confidence:P0})";

            var decisionResult = _ruleEngineService.Evaluate(snapshot.CurrentLayer, inference);
            if (!decisionResult.Succeeded || decisionResult.Data is null)
            {
                SetError("规则判定失败。", decisionResult.Message);
                return;
            }

            var decision = decisionResult.Data;
            DecisionText = $"{decision.Code} - {decision.Message}";

            StatusBrush = decision.IsPass ? Brushes.DarkGreen : Brushes.OrangeRed;
            StatusText = decision.IsPass ? "当前层判定通过。" : "当前层判定 NG，请人工复核。";
        }

        /// <summary>
        /// 推进到下一层。
        /// </summary>
        public void MoveToNextLayer()
        {
            var moveResult = _runtimeStateMachineService.MoveToNextLayer();
            if (!moveResult.Succeeded)
            {
                SetError("状态机切层失败。", moveResult.Message);
                return;
            }

            RefreshSnapshot();
            StatusBrush = Brushes.DarkGreen;
            StatusText = moveResult.Message;
        }

        /// <summary>
        /// 重置运行状态。
        /// </summary>
        public void ResetRuntime()
        {
            _runtimeStateMachineService.Reset();
            InferenceText = "-";
            DecisionText = "-";
            RefreshSnapshot();
            StatusBrush = Brushes.DarkGreen;
            StatusText = "运行状态已重置。";
        }

        /// <inheritdoc />
        public event PropertyChangedEventHandler? PropertyChanged;

        private void RefreshSnapshot()
        {
            var snapshot = _runtimeStateMachineService.GetSnapshot();
            LayerText = $"{snapshot.CurrentLayer}/{snapshot.TotalLayers}";
        }

        private void SetError(string title, string message)
        {
            StatusBrush = Brushes.OrangeRed;
            StatusText = $"{title} {message}";
        }

        private void SetProperty<T>(ref T field, T value, [CallerMemberName] string? propertyName = null)
        {
            if (EqualityComparer<T>.Default.Equals(field, value))
            {
                return;
            }

            field = value;
            PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
        }
    }
}