using System;
using System.Linq;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Input;
using LocalizationTool.Models;
using LocalizationTool.Services;
using LocalizationTool.ViewModels;

namespace LocalizationTool
{
    /// <summary>主窗口：只负责视图（动态列、下拉同步、浏览对话框），业务全在 MainViewModel。</summary>
    public partial class MainWindow
    {
        private readonly MainViewModel _vm;
        private bool _suppressLangSync;

        public MainWindow()
        {
            InitializeComponent();
            Icon = App.AppIcon;
            _vm = new MainViewModel();
            DataContext = _vm;

            _vm.LangOptionsChanged += RefreshLangCombo;
            _vm.SelectedLangsChanged += RebuildGrid;

            if (!Translation.Provider.IsConfigured)
                _vm.Stats = "提示：未配置翻译 API Key，可在“翻译设置”填写后再使用自动翻译。";
        }

        /// <summary>语言下拉选项变化：填充并默认全选（抑制回环触发）。</summary>
        private void RefreshLangCombo()
        {
            _suppressLangSync = true;
            CmbTargetLangs.SelectedItems.Clear();
            foreach (var o in _vm.LangOptions) CmbTargetLangs.SelectedItems.Add(o);
            _suppressLangSync = false;
        }

        /// <summary>勾选变化 → 同步 ViewModel（表格列由 VM 的 SelectedLangsChanged 事件驱动重建）。</summary>
        private void CmbTargetLangs_SelectionChanged(object sender, SelectionChangedEventArgs e)
        {
            if (_suppressLangSync) return;
            _vm.SetSelectedLangs(CmbTargetLangs.SelectedItems
                .OfType<LangOption>()
                .Select(o => o.LanguageCode));
        }

        private void BtnBrowse_Click(object sender, RoutedEventArgs e)
        {
            var dlg = new System.Windows.Forms.FolderBrowserDialog();
            if (dlg.ShowDialog() == System.Windows.Forms.DialogResult.OK)
                _vm.LoadDirectory(dlg.SelectedPath);
        }

        /// <summary>右键点击行时自动选中它（若点击行已在多选集合内则保留多选，供"删除选中行"批量使用）。</summary>
        private void Grid_PreviewMouseRightButtonDown(object sender, MouseButtonEventArgs e)
        {
            var row = ItemsControl.ContainerFromElement(Grid, e.OriginalSource as DependencyObject) as DataGridRow;
            if (row != null && !Grid.SelectedItems.Contains(row.Item))
                Grid.SelectedItem = row.Item;
        }

        /// <summary>按勾选的语言动态生成表格列（序号 + 中文源文 + 语言列 + 缺译概览）。</summary>
        private void RebuildGrid()
        {
            Grid.Columns.Clear();

            Grid.Columns.Add(new DataGridTextColumn
            {
                Header = "#",
                Binding = new Binding(nameof(RowVm.Index)) { Mode = BindingMode.OneWay },
                Width = DataGridLength.Auto,
                CanUserResize = false,
                IsReadOnly = true,
            });
            Grid.Columns.Add(new DataGridTextColumn
            {
                Header = "中文源文",
                Binding = new Binding(nameof(RowVm.Key)) { Mode = BindingMode.OneWay },
                Width = new DataGridLength(280),
                IsReadOnly = true,
            });

            foreach (var lang in _vm.SelectedLangs)
            {
                var code = lang.LanguageCode;

                var column = new DataGridTextColumn
                {
                    Header = $"{lang.LanguageName} ({code})",
                    Binding = new Binding($"Cells[{code}].Value") { Mode = BindingMode.TwoWay },
                    Width = new DataGridLength(220),
                };

                // 必须 BasedOn 全局（HandyControl）隐式样式，否则该列会退化成 WPF 原生模板，
                // 表现为译文文字靠上而不是像中文列那样垂直居中
                var cellStyle = new Style(typeof(DataGridCell), Grid.TryFindResource(typeof(DataGridCell)) as Style);
                var trigger = new DataTrigger
                {
                    Binding = new Binding($"Cells[{code}].HasIssue"),
                    Value = true,
                };
                trigger.Setters.Add(new Setter(DataGridCell.BorderBrushProperty, System.Windows.Media.Brushes.Red));
                trigger.Setters.Add(new Setter(DataGridCell.BorderThicknessProperty, new Thickness(2)));
                cellStyle.Triggers.Add(trigger);
                column.CellStyle = cellStyle;

                var elementStyle = new Style(typeof(TextBlock), Grid.TryFindResource(typeof(TextBlock)) as Style);
                elementStyle.Setters.Add(new Setter(TextBlock.VerticalAlignmentProperty, VerticalAlignment.Center));
                elementStyle.Setters.Add(new Setter(
                    System.Windows.Controls.ToolTipService.ToolTipProperty,
                    new Binding($"Cells[{code}].IssueMessage")));
                column.ElementStyle = elementStyle;

                Grid.Columns.Add(column);
            }

            Grid.Columns.Add(new DataGridTextColumn
            {
                Header = "缺译",
                Binding = new Binding(nameof(RowVm.MissingText)) { Mode = BindingMode.OneWay },
                Width = new DataGridLength(70),
                CanUserResize = false,
                IsReadOnly = true,
            });
        }
    }
}