using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.ComponentModel;
using System.Runtime.CompilerServices;

namespace AI.Models.SpecialMessages
{
    /// <summary>
    /// 网格化参数卡片的执行阶段
    /// </summary>
    public enum GriddingParamCardPhase
    {
        /// <summary>正在从业务层加载参数</summary>
        Loading = 0,
        /// <summary>参数已加载，等待用户编辑并点击生成</summary>
        Ready = 1,
        /// <summary>正在执行成图</summary>
        Generating = 2,
        /// <summary>成图完成</summary>
        Done = 3,
        /// <summary>出错（加载失败或成图失败）</summary>
        Error = 4,
    }

    /// <summary>
    /// 网格化参数设置综合卡片：将「获取参数」「编辑参数」「执行成图」合并到一张卡片。
    /// 整个业务流程由卡片本身驱动，AI 只需调用一次展示此卡片；
    /// 用户确认参数后点击"生成"按钮，卡片自动完成参数设置和成图，最终摘要发回 AI。
    /// </summary>
    public class GriddingParamCardMessage : ISpecialMessage, INotifyPropertyChanged
    {
        private GriddingParamCardPhase _phase = GriddingParamCardPhase.Loading;
        private string _statusMessage = string.Empty;
        private string _generateButtonLabel = "生成";

        public string Id { get; set; } = Guid.NewGuid().ToString();
        public string TypeName => "GriddingParamCard";
        public bool IsLive => false;

        // ── 阶段控制 ──────────────────────────────────────────────────────────

        public GriddingParamCardPhase Phase
        {
            get => _phase;
            set
            {
                if (SetProperty(ref _phase, value))
                {
                    OnPropertyChanged(nameof(IsLoading));
                    OnPropertyChanged(nameof(ShowItems));
                    OnPropertyChanged(nameof(ShowGenerateButton));
                    OnPropertyChanged(nameof(IsGenerating));
                    OnPropertyChanged(nameof(IsDone));
                    OnPropertyChanged(nameof(IsError));
                    OnPropertyChanged(nameof(ShowDoneBadge));
                    OnPropertyChanged(nameof(ShowErrorMessage));
                }
            }
        }

        // ── 状态派生属性 ─────────────────────────────────────────────────────

        /// <summary>是否正在加载参数（显示 loading 占位）</summary>
        public bool IsLoading => _phase == GriddingParamCardPhase.Loading;

        /// <summary>是否显示参数列表（非 Loading 阶段）</summary>
        public bool ShowItems => _phase != GriddingParamCardPhase.Loading;

        /// <summary>是否显示"生成"按钮（Ready 阶段）</summary>
        public bool ShowGenerateButton => _phase == GriddingParamCardPhase.Ready;

        /// <summary>是否正在执行成图</summary>
        public bool IsGenerating => _phase == GriddingParamCardPhase.Generating;

        /// <summary>成图是否已完成</summary>
        public bool IsDone => _phase == GriddingParamCardPhase.Done;

        /// <summary>是否处于错误状态</summary>
        public bool IsError => _phase == GriddingParamCardPhase.Error;

        /// <summary>是否显示"成图完成"标记</summary>
        public bool ShowDoneBadge => _phase == GriddingParamCardPhase.Done;

        /// <summary>是否显示错误信息</summary>
        public bool ShowErrorMessage => _phase == GriddingParamCardPhase.Error && !string.IsNullOrEmpty(_statusMessage);

        // ── 状态文案 ──────────────────────────────────────────────────────────

        /// <summary>状态提示文案（加载中、错误信息、成功提示等）</summary>
        public string StatusMessage
        {
            get => _statusMessage;
            set
            {
                SetProperty(ref _statusMessage, value ?? string.Empty);
                OnPropertyChanged(nameof(ShowErrorMessage));
                OnPropertyChanged(nameof(HasStatusMessage));
            }
        }

        /// <summary>是否有状态信息</summary>
        public bool HasStatusMessage => !string.IsNullOrEmpty(_statusMessage);

        /// <summary>"生成"按钮文案（执行中可切换为"生成中..."）</summary>
        public string GenerateButtonLabel
        {
            get => _generateButtonLabel;
            set => SetProperty(ref _generateButtonLabel, value ?? "生成");
        }

        // ── 参数项列表 ────────────────────────────────────────────────────────

        /// <summary>参数项列表（从业务层加载后填充，用户可编辑）</summary>
        public ObservableCollection<ParameterSetItem> Items { get; } = new ObservableCollection<ParameterSetItem>();

        // ── INotifyPropertyChanged ───────────────────────────────────────────

        public event PropertyChangedEventHandler? PropertyChanged;

        protected void OnPropertyChanged([CallerMemberName] string? propertyName = null) =>
            PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));

        protected bool SetProperty<T>(ref T field, T value, [CallerMemberName] string? propertyName = null)
        {
            if (EqualityComparer<T>.Default.Equals(field, value)) return false;
            field = value;
            OnPropertyChanged(propertyName);
            return true;
        }
    }
}