// timeline.json を読み、現在アクティブなタイムラインへアイテムを一括配置する。
// スパイク方針: コンパイル時に確実な型(Timeline/BaseItem/各アイテムの空ctor)だけ静的に使い、
// シグネチャが不確かな箇所(プロパティ型・AddItems)はリフレクションで解決してログに残す。

using System.IO;
using System.Reflection;
using System.Text.Json;
using System.Windows;
using YukkuriMovieMaker.Project;
using YukkuriMovieMaker.Project.Items;

namespace KakiniwaYmm4Import;

public static class Importer
{
    public static void Run(string packDir, Action<string> log)
    {
        var jsonPath = Path.Combine(packDir, "timeline.json");
        if (!File.Exists(jsonPath))
        {
            log($"timeline.json がありません: {jsonPath}");
            return;
        }
        var pack = JsonSerializer.Deserialize<Pack>(
            File.ReadAllText(jsonPath),
            new JsonSerializerOptions { PropertyNameCaseInsensitive = true });
        if (pack is null)
        {
            log("timeline.json の解析に失敗");
            return;
        }
        log($"読み込みOK: {pack.Title}『{pack.Episode}』 events={pack.Events.Count} chars={pack.Characters.Count}");

        var timeline = FindActiveTimeline(log);
        if (timeline is null) return;

        var fps = ReadFps(timeline, log);
        int F(double sec) => (int)Math.Round(sec * fps);

        var evs = pack.Events;
        var totalEnd = evs.Count == 0 ? 0 : evs.Max(e => e.Start + e.Seconds) + 1.0;

        // レイヤー割り当て: 0=背景 1=BGM 2=SE 3=ト書き 4以降=キャラごとに(立ち絵, ボイス)
        var charLayer = new Dictionary<string, int>();
        var nextCharLayer = 4;
        int LayerOf(string charId, bool voice)
        {
            if (!charLayer.TryGetValue(charId, out var baseLayer))
            {
                baseLayer = nextCharLayer;
                nextCharLayer += 2;
                charLayer[charId] = baseLayer;
            }
            return voice ? baseLayer + 1 : baseLayer;
        }

        double NextStartOfType(int i, params string[] types)
        {
            for (var j = i + 1; j < evs.Count; j++)
                if (types.Contains(evs[j].Type)) return evs[j].Start;
            return totalEnd;
        }

        var items = new List<BaseItem>();
        var skipped = new List<string>();

        for (var i = 0; i < evs.Count; i++)
        {
            var ev = evs[i];
            switch (ev.Type)
            {
                case "bg":
                {
                    var path = ResolveAsset(packDir, ev.Asset, skipped, ev);
                    if (path is null) break;
                    var item = new ImageItem();
                    SetProps(item, log,
                        ("FilePath", path), ("Frame", F(ev.Start)), ("Layer", 0),
                        ("Length", F(NextStartOfType(i, "bg") - ev.Start)),
                        ("Label", $"背景: {ev.Asset!.Name}"));
                    items.Add(item);
                    break;
                }
                case "bgm":
                {
                    var path = ResolveAsset(packDir, ev.Asset, skipped, ev);
                    if (path is null) break;
                    var item = new AudioItem();
                    SetProps(item, log,
                        ("FilePath", path), ("Frame", F(ev.Start)), ("Layer", 1),
                        ("Length", F(NextStartOfType(i, "bgm", "bgm_stop") - ev.Start)),
                        ("Label", $"BGM: {ev.Asset!.Name}"));
                    items.Add(item);
                    break;
                }
                case "se":
                {
                    var path = ResolveAsset(packDir, ev.Asset, skipped, ev);
                    if (path is null) break;
                    var item = new AudioItem();
                    SetProps(item, log,
                        ("FilePath", path), ("Frame", F(ev.Start)), ("Layer", 2),
                        ("Length", F(1.0)),
                        ("Label", $"SE: {ev.Asset!.Name}"));
                    items.Add(item);
                    break;
                }
                case "stage":
                {
                    var item = new TextItem();
                    SetProps(item, log,
                        ("Text", $"({ev.Text})"), ("Frame", F(ev.Start)), ("Layer", 3),
                        ("Length", F(ev.Seconds)), ("IsHidden", true),
                        ("Label", "ト書き"));
                    items.Add(item);
                    break;
                }
                case "serif":
                {
                    var chara = pack.Characters.FirstOrDefault(c => c.Id == ev.Speaker);
                    var ymm4Name = chara?.Ymm4Name ?? chara?.Name ?? ev.SpeakerName ?? "";

                    var voice = new VoiceItem();
                    SetProps(voice, log,
                        ("CharacterName", ymm4Name), ("Serif", ev.Text ?? ""),
                        ("Frame", F(ev.Start)), ("Layer", LayerOf(ev.Speaker ?? "?", voice: true)),
                        ("Length", F(ev.Seconds)));
                    if (!string.IsNullOrEmpty(ev.Reading))
                        SetProps(voice, log, ("Pronounce", ev.Reading!));
                    items.Add(voice);

                    // 立ち絵(スパイク版): 表情の画像/PSDを ImageItem としてセリフ区間に置く。
                    // 本来は TachieItem + TachieFaceParameter(残調査)。
                    var portrait = ResolvePortrait(packDir, chara, ev.Expression);
                    if (portrait is not null)
                    {
                        var img = new ImageItem();
                        SetProps(img, log,
                            ("FilePath", portrait), ("Frame", F(ev.Start)),
                            ("Layer", LayerOf(ev.Speaker ?? "?", voice: false)),
                            ("Length", F(ev.Seconds)),
                            ("Label", $"{chara?.Name}({ev.Expression ?? "既定"})"));
                        items.Add(img);
                    }

                    foreach (var se in ev.Se)
                    {
                        var sePath = ResolveAsset(packDir, se, skipped, ev);
                        if (sePath is null) continue;
                        var item = new AudioItem();
                        SetProps(item, log,
                            ("FilePath", sePath), ("Frame", F(ev.Start)), ("Layer", 2),
                            ("Length", F(1.0)), ("Label", $"SE: {se.Name}"));
                        items.Add(item);
                    }
                    break;
                }
                case "bgm_stop":
                case "custom":
                    break; // アイテム化しない(bgm_stop は bgm の終端計算で消費済み)
                default:
                    skipped.Add($"no.{ev.No}: 未知の type '{ev.Type}'");
                    break;
            }
        }

        log($"アイテム生成: {items.Count}件 (fps={fps})");
        foreach (var s in skipped) log($"  スキップ: {s}");

        AddItems(timeline, items, log);
    }

    /// <summary>MainWindow.DataContext → ActiveTimelineViewModel → 内部の Timeline モデルを辿る</summary>
    static Timeline? FindActiveTimeline(Action<string> log)
    {
        var mainVm = Application.Current.MainWindow?.DataContext;
        if (mainVm is null) { log("NG: MainWindow.DataContext が null"); return null; }
        log($"MainViewModel: {mainVm.GetType().FullName}");

        var tlVm = mainVm.GetType().GetProperty("ActiveTimelineViewModel")?.GetValue(mainVm);
        if (tlVm is null) { log("NG: ActiveTimelineViewModel が null(プロジェクトが開かれていない?)"); return null; }
        log($"TimelineViewModel: {tlVm.GetType().FullName}");

        // ViewModel が抱えている Timeline モデルをフィールド/プロパティから探す
        for (var t = tlVm.GetType(); t is not null; t = t.BaseType)
        {
            foreach (var f in t.GetFields(BindingFlags.Instance | BindingFlags.NonPublic | BindingFlags.Public))
            {
                if (typeof(Timeline).IsAssignableFrom(f.FieldType) && f.GetValue(tlVm) is Timeline tl)
                {
                    log($"Timeline 取得: フィールド {t.Name}.{f.Name}");
                    return tl;
                }
            }
            foreach (var p in t.GetProperties(BindingFlags.Instance | BindingFlags.NonPublic | BindingFlags.Public))
            {
                if (typeof(Timeline).IsAssignableFrom(p.PropertyType) && p.GetIndexParameters().Length == 0
                    && p.GetValue(tlVm) is Timeline tl)
                {
                    log($"Timeline 取得: プロパティ {t.Name}.{p.Name}");
                    return tl;
                }
            }
        }
        log("NG: TimelineViewModel から Timeline モデルを見つけられなかった");
        return null;
    }

    static double ReadFps(Timeline timeline, Action<string> log)
    {
        try
        {
            var vi = timeline.GetType().GetProperty("VideoInfo")?.GetValue(timeline);
            var fpsObj = vi?.GetType().GetProperty("FPS")?.GetValue(vi);
            if (fpsObj is not null)
            {
                var fps = Convert.ToDouble(fpsObj);
                if (fps > 0) return fps;
            }
        }
        catch (Exception ex) { log($"FPS取得失敗({ex.Message})→ 30 とみなす"); }
        return 30;
    }

    static string? ResolveAsset(string packDir, PackAssetRef? asset, List<string> skipped, PackEvent ev)
    {
        if (asset?.Path is null)
        {
            skipped.Add($"no.{ev.No}: 素材不足 '{asset?.Name ?? "?"}'(path=null)");
            return null;
        }
        var full = Path.GetFullPath(Path.Combine(packDir, asset.Path));
        if (!File.Exists(full))
        {
            skipped.Add($"no.{ev.No}: 素材ファイルが実在しない {asset.Path}");
            return null;
        }
        return full;
    }

    static string? ResolvePortrait(string packDir, PackCharacter? chara, string? expression)
    {
        if (chara is null) return null;
        var expr = expression is null
            ? chara.Expressions.FirstOrDefault(e => e.Default) ?? chara.Expressions.FirstOrDefault()
            : chara.Expressions.FirstOrDefault(e => e.Id == expression || e.Label == expression);
        if (expr is null) return null;
        string? rel = expr.Psd?.Path ?? (expr.File is not null && chara.PortraitDir is not null
            ? $"{chara.PortraitDir}/{expr.File}"
            : null);
        if (rel is null) return null;
        var full = Path.GetFullPath(Path.Combine(packDir, rel));
        return File.Exists(full) ? full : null;
    }

    /// <summary>プロパティ型の食い違いに耐えるためリフレクションで設定(int/double/bool/enum は変換)</summary>
    static void SetProps(object item, Action<string> log, params (string Name, object Value)[] props)
    {
        foreach (var (name, value) in props)
        {
            try
            {
                var p = item.GetType().GetProperty(name);
                if (p is null || !p.CanWrite)
                {
                    log($"  [{item.GetType().Name}] プロパティ {name} が無い/書けない");
                    continue;
                }
                var target = Nullable.GetUnderlyingType(p.PropertyType) ?? p.PropertyType;
                object converted = value;
                if (!target.IsInstanceOfType(value))
                    converted = target.IsEnum
                        ? Enum.ToObject(target, Convert.ToInt32(value))
                        : Convert.ChangeType(value, target);
                p.SetValue(item, converted);
            }
            catch (Exception ex)
            {
                log($"  [{item.GetType().Name}] {name} 設定失敗: {ex.Message}");
            }
        }
    }

    /// <summary>Timeline.AddItems / TryAddItems をリフレクションで探して呼ぶ(シグネチャをログに残す)</summary>
    static void AddItems(Timeline timeline, List<BaseItem> items, Action<string> log)
    {
        if (items.Count == 0) { log("追加するアイテムがありません"); return; }

        var candidates = typeof(Timeline)
            .GetMethods(BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic)
            .Where(m => m.Name is "AddItems" or "TryAddItems")
            .ToArray();
        foreach (var m in candidates)
            log($"候補メソッド: {m.Name}({string.Join(", ", m.GetParameters().Select(p => $"{p.ParameterType.Name} {p.Name}"))})");

        foreach (var m in candidates.OrderBy(m => m.Name == "AddItems" ? 0 : 1)
                                    .ThenBy(m => m.GetParameters().Length))
        {
            var ps = m.GetParameters();
            if (ps.Length == 0 || !ps[0].ParameterType.IsInstanceOfType(items)) continue;
            var args = new object?[ps.Length];
            args[0] = items;
            var ok = true;
            for (var i = 1; i < ps.Length; i++)
            {
                if (ps[i].HasDefaultValue) args[i] = ps[i].DefaultValue;
                else if (ps[i].ParameterType.IsValueType) args[i] = Activator.CreateInstance(ps[i].ParameterType);
                else { ok = false; break; }
            }
            if (!ok) continue;
            try
            {
                var result = m.Invoke(timeline, args);
                log($"実行: {m.Name} → {(result is null ? "完了" : result)}");
                log($"配置完了: {items.Count}アイテム");
                return;
            }
            catch (Exception ex)
            {
                log($"{m.Name} 失敗: {ex.InnerException?.Message ?? ex.Message}");
            }
        }
        log("NG: 適合する AddItems を呼べなかった(上の候補ログを見て次の一手を考える)");
    }
}