using FlatRender.StudioSvc.Domain.Entities;
using FlatRender.StudioSvc.Domain.Enums;
using FlatRender.StudioSvc.Infrastructure.Data;
using FlatRender.StudioSvc.Models.Requests;
using FlatRender.StudioSvc.Models.Responses;
using Microsoft.EntityFrameworkCore;

namespace FlatRender.StudioSvc.Application.Services;

public class StudioService(StudioDbContext db)
{
    public async Task<PagedResponse<SavedProjectSummaryResponse>> ListProjectsAsync(
        Guid userId, SavedProjectListRequest req)
    {
        var q = db.SavedProjects.Where(x => x.UserId == userId);

        if (!string.IsNullOrWhiteSpace(req.Q))
            q = q.Where(x => EF.Functions.ILike(x.Name, $"%{req.Q}%"));

        if (!string.IsNullOrWhiteSpace(req.Type) &&
            Enum.TryParse<SavedProjectType>(req.Type, true, out var t))
            q = q.Where(x => x.Type == t);

        var total = await q.LongCountAsync();
        var items = await q
            .OrderByDescending(x => x.LastEditDate)
            .Skip((req.Page - 1) * req.PageSize)
            .Take(req.PageSize)
            .ToListAsync();

        return new PagedResponse<SavedProjectSummaryResponse>(
            items.Select(MapSummary),
            new PaginationMeta(req.Page, req.PageSize, total,
                (int)Math.Ceiling((double)total / req.PageSize)));
    }

    public async Task<SavedProjectFullResponse> GetProjectAsync(Guid id, Guid userId)
    {
        var p = await LoadProjectQuery()
            .FirstOrDefaultAsync(x => x.Id == id && x.UserId == userId)
            ?? throw new KeyNotFoundException($"Project {id} not found");

        return MapFull(p);
    }

    /// <summary>Internal: load project without user-ownership check (for service-to-service calls).</summary>
    public async Task<SavedProjectFullResponse> GetProjectForRenderAsync(Guid id)
    {
        var p = await LoadProjectQuery()
            .FirstOrDefaultAsync(x => x.Id == id)
            ?? throw new KeyNotFoundException($"Project {id} not found");

        return MapFull(p);
    }

    private IQueryable<Domain.Entities.SavedProject> LoadProjectQuery() =>
        db.SavedProjects
            .Include(x => x.Scenes.OrderBy(s => s.Sort))
                .ThenInclude(s => s.Contents.OrderBy(c => c.Sort))
            .Include(x => x.Scenes).ThenInclude(s => s.Colors.OrderBy(c => c.Sort))
            .Include(x => x.Scenes).ThenInclude(s => s.ColorPresets.OrderBy(c => c.Sort))
                .ThenInclude(cp => cp.Items.OrderBy(i => i.Sort))
            .Include(x => x.Scenes).ThenInclude(s => s.Characters)
                .ThenInclude(ch => ch.Controllers.OrderBy(c => c.Sort))
            .Include(x => x.SharedColors.OrderBy(c => c.Sort))
            .Include(x => x.SharedColorPresets.OrderBy(c => c.Sort))
                .ThenInclude(cp => cp.Items.OrderBy(i => i.Sort))
            .Include(x => x.SharedLayers.OrderBy(l => l.Sort));

    public async Task<SavedProjectFullResponse> CreateProjectAsync(
        Guid userId, Guid tenantId, CreateSavedProjectRequest req)
    {
        var project = new SavedProject
        {
            TenantId = tenantId,
            UserId = userId,
            OriginalProjectId = req.OriginalProjectId,
            OriginalProjectName = req.Name ?? $"Project {DateTime.UtcNow:yyyy-MM-dd}",
            Name = req.Name ?? $"Project {DateTime.UtcNow:yyyy-MM-dd}",
            SelectedPresetStoryId = req.PresetStoryId,
            ProjectDurationSec = 0,
        };

        await using var tx = await db.Database.BeginTransactionAsync();
        db.SavedProjects.Add(project);
        await db.SaveChangesAsync();

        // Deep-copy the template's scene graph (scenes + content/colour elements) from
        // the content schema so the new project opens editable in the studio. Same DB,
        // so this is one atomic cross-schema copy.
        if (req.CopyDefaultValues && req.OriginalProjectId != Guid.Empty)
            await CopyTemplateGraphAsync(project.Id, req.OriginalProjectId);

        await tx.CommitAsync();
        return await GetProjectAsync(project.Id, userId);
    }

    /// <summary>
    /// Copies a content template project's scenes, content elements and colour elements
    /// into a freshly-created editable project. Runs inside the caller's transaction;
    /// the temp scene-id map drops on commit. Same Postgres DB → atomic cross-schema copy.
    /// </summary>
    private async Task CopyTemplateGraphAsync(Guid savedProjectId, Guid originalProjectId)
    {
        // 1. scenes → capture old→new id mapping in a temp table
        await db.Database.ExecuteSqlRawAsync(@"
            CREATE TEMP TABLE _scene_map ON COMMIT DROP AS
            WITH ins AS (
                INSERT INTO studio.saved_scenes
                    (saved_project_id, original_scene_id, key, title, image, demo,
                     scene_color_svg, scene_type, sort, scene_length_sec, min_duration_sec,
                     max_duration_sec, overlap_at_end_sec, can_handle_duration,
                     manual_color_selection, created_at, updated_at)
                SELECT {0}, s.id, s.key, s.title, s.image, s.demo, s.scene_color_svg,
                       s.scene_type::text, s.sort, COALESCE(s.default_duration_sec, 0),
                       s.min_duration_sec, s.max_duration_sec, s.overlap_at_end_sec,
                       s.can_handle_duration, s.manual_color_selection, now(), now()
                FROM content.scenes s
                WHERE s.project_id = {1} AND s.deleted_at IS NULL AND s.is_active = true
                RETURNING id AS new_id, original_scene_id AS old_id
            )
            SELECT new_id, old_id FROM ins;",
            savedProjectId, originalProjectId);

        // 2. content elements — incl. repeater children flattened via repeater_item_key
        await db.Database.ExecuteSqlRawAsync(@"
            INSERT INTO studio.saved_scene_contents
                (saved_scene_id, key, title, localized_title, hint, type, value,
                 font_face, font_face_name, font_size, default_font_size, default_font_face,
                 justify, position_in_container, direction_layer_value, is_text_box,
                 ai_input_type, mapped_list, thumbnail, sort, repeater_item_key,
                 repeater_index, status, created_at, updated_at)
            SELECT sm.new_id, ce.key, ce.title, ce.localized_title, ce.hint, ce.type::text,
                   ce.default_value, ce.font_face, ce.font_face_name, ce.font_size,
                   ce.default_font_size, ce.default_font_face, ce.justify::text,
                   ce.position_in_container, ce.direction_layer_value, ce.is_text_box,
                   ce.ai_input_type::text, ce.mapped_list, ce.thumbnail, ce.sort,
                   ri.repeat_item_key, ri.sort, 'default', now(), now()
            FROM content.scene_content_elements ce
            JOIN _scene_map sm ON sm.old_id = ce.scene_id
            LEFT JOIN content.repeater_items ri ON ri.id = ce.repeater_item_id;");

        // 3. colour elements
        await db.Database.ExecuteSqlRawAsync(@"
            INSERT INTO studio.saved_scene_colors
                (saved_scene_id, element_key, title, icon, attr_value, value, is_selected, sort)
            SELECT sm.new_id, ce.element_key, ce.title, ce.icon, ce.attr_value::text,
                   COALESCE(ce.default_color, ''), false, ce.sort
            FROM content.scene_color_elements ce
            JOIN _scene_map sm ON sm.old_id = ce.scene_id;");

        // 3b. characters — studio's `key` is a uuid; store the original character id
        await db.Database.ExecuteSqlRawAsync(@"
            INSERT INTO studio.saved_scene_characters (saved_scene_id, key, name, icon)
            SELECT sm.new_id, ch.id, ch.name, ch.icon
            FROM content.scene_characters ch
            JOIN _scene_map sm ON sm.old_id = ch.scene_id;");

        // 3c. character controllers (correlate the new character by scene + original id)
        await db.Database.ExecuteSqlRawAsync(@"
            INSERT INTO studio.saved_scene_character_controllers
                (saved_scene_character_id, name, key, value, sort)
            SELECT sc.id, cc.name, cc.key, cc.default_value, cc.sort
            FROM content.scene_character_controllers cc
            JOIN content.scene_characters cch ON cch.id = cc.scene_character_id
            JOIN _scene_map sm ON sm.old_id = cch.scene_id
            JOIN studio.saved_scene_characters sc
              ON sc.saved_scene_id = sm.new_id AND sc.key = cch.id;");

        // 3d. colour presets
        await db.Database.ExecuteSqlRawAsync(@"
            INSERT INTO studio.saved_scene_color_presets (saved_scene_id, is_selected, sort)
            SELECT sm.new_id, false, cp.sort
            FROM content.scene_color_presets cp
            JOIN _scene_map sm ON sm.old_id = cp.scene_id;");

        // 3e. colour preset items (correlate the new preset by scene + sort)
        await db.Database.ExecuteSqlRawAsync(@"
            INSERT INTO studio.saved_scene_color_preset_items (preset_id, element_key, value, sort)
            SELECT sp.id, ci.element_key, ci.value, ci.sort
            FROM content.scene_color_preset_items ci
            JOIN content.scene_color_presets cp ON cp.id = ci.preset_id
            JOIN _scene_map sm ON sm.old_id = cp.scene_id
            JOIN studio.saved_scene_color_presets sp
              ON sp.saved_scene_id = sm.new_id AND sp.sort = cp.sort;");

        // 4. shared (project-level) colours — frshare frd_* controls
        await db.Database.ExecuteSqlRawAsync(@"
            INSERT INTO studio.saved_shared_colors
                (saved_project_id, element_key, title, icon, attr_value, value, is_selected, sort)
            SELECT {0}, sc.element_key, sc.title, sc.icon, sc.attr_value::text,
                   COALESCE(sc.default_color, ''), false, sc.sort
            FROM content.shared_colors sc
            WHERE sc.project_id = {1};",
            savedProjectId, originalProjectId);
    }

    public async Task<SavedProjectFullResponse> UpdateProjectAsync(
        Guid id, Guid userId, UpdateSavedProjectRequest req)
    {
        var project = await db.SavedProjects
            .FirstOrDefaultAsync(x => x.Id == id && x.UserId == userId)
            ?? throw new KeyNotFoundException($"Project {id} not found");

        if (req.Name != null) project.Name = req.Name;
        if (req.Image != null) project.Image = req.Image;
        if (req.Type != null && Enum.TryParse<SavedProjectType>(req.Type, true, out var t))
            project.Type = t;
        if (req.MusicFileId.HasValue) project.MusicFileId = req.MusicFileId;
        if (req.MusicTrackId.HasValue) project.MusicTrackId = req.MusicTrackId;
        if (req.MusicVolume.HasValue) project.MusicVolume = req.MusicVolume.Value;
        if (req.VoiceoverFileId.HasValue) project.VoiceoverFileId = req.VoiceoverFileId;
        if (req.VoiceoverVolume.HasValue) project.VoiceoverVolume = req.VoiceoverVolume.Value;
        if (req.VoiceoverRecordedInBrowser.HasValue)
            project.VoiceoverRecordedInBrowser = req.VoiceoverRecordedInBrowser.Value;
        if (req.SfxVolume.HasValue) project.SfxVolume = req.SfxVolume.Value;
        if (req.SfxEnabled.HasValue) project.SfxEnabled = req.SfxEnabled.Value;
        if (req.AudioVisualizerMusicUrl != null) project.AudioVisualizerMusicUrl = req.AudioVisualizerMusicUrl;
        if (req.AudioVisualizerDurationSec.HasValue)
            project.AudioVisualizerDurationSec = req.AudioVisualizerDurationSec;
        if (req.ManualColorPicker.HasValue) project.ManualColorPicker = req.ManualColorPicker.Value;
        if (req.SelectedPresetStoryId.HasValue) project.SelectedPresetStoryId = req.SelectedPresetStoryId;
        if (req.LastEditStep != null) project.LastEditStep = req.LastEditStep;
        if (req.EditState != null) project.EditState = req.EditState;

        project.LastEditDate = DateTime.UtcNow;
        project.UpdatedAt = DateTime.UtcNow;
        await db.SaveChangesAsync();

        return await GetProjectAsync(id, userId);
    }

    public async Task DeleteProjectAsync(Guid id, Guid userId)
    {
        var project = await db.SavedProjects
            .FirstOrDefaultAsync(x => x.Id == id && x.UserId == userId)
            ?? throw new KeyNotFoundException($"Project {id} not found");
        project.DeletedAt = DateTime.UtcNow;
        await db.SaveChangesAsync();
    }

    /// <summary>
    /// Full scene save — replaces all scene data atomically.
    /// Called by the studio editor on every save checkpoint.
    /// </summary>
    public async Task<SavedProjectFullResponse> SaveScenesAsync(
        Guid projectId, Guid userId, List<SaveSceneRequest> scenes)
    {
        var project = await db.SavedProjects
            .FirstOrDefaultAsync(x => x.Id == projectId && x.UserId == userId)
            ?? throw new KeyNotFoundException($"Project {projectId} not found");

        // Delete existing scenes (cascade deletes children)
        var existing = await db.SavedScenes
            .Where(x => x.SavedProjectId == projectId).ToListAsync();
        db.SavedScenes.RemoveRange(existing);

        foreach (var (sceneReq, idx) in scenes.Select((s, i) => (s, i)))
        {
            var scene = new SavedScene
            {
                SavedProjectId = projectId,
                OriginalSceneId = sceneReq.OriginalSceneId,
                Key = sceneReq.Key,
                Title = sceneReq.Title,
                Image = sceneReq.Image,
                SceneColorSvg = sceneReq.SceneColorSvg,
                SceneType = sceneReq.SceneType,
                Sort = sceneReq.Sort,
                SceneLengthSec = sceneReq.SceneLengthSec,
                MinDurationSec = sceneReq.MinDurationSec,
                MaxDurationSec = sceneReq.MaxDurationSec,
                OverlapAtEndSec = sceneReq.OverlapAtEndSec,
                CanHandleDuration = sceneReq.CanHandleDuration,
                ManualColorSelection = sceneReq.ManualColorSelection,
            };

            foreach (var c in sceneReq.Contents)
                scene.Contents.Add(MapContentEntity(c));

            foreach (var c in sceneReq.Colors)
                scene.Colors.Add(new SavedSceneColor
                {
                    ElementKey = c.ElementKey, Title = c.Title, Icon = c.Icon,
                    AttrValue = c.AttrValue, Value = c.Value, IsSelected = c.IsSelected, Sort = c.Sort
                });

            db.SavedScenes.Add(scene);
        }

        // Sync shared colors
        var sharedColors = scenes.SelectMany(s => s.SharedColors).DistinctBy(x => x.ElementKey).ToList();
        if (sharedColors.Count > 0)
        {
            var existingSC = await db.SavedSharedColors
                .Where(x => x.SavedProjectId == projectId).ToListAsync();
            db.SavedSharedColors.RemoveRange(existingSC);
            foreach (var c in sharedColors)
                db.SavedSharedColors.Add(new SavedSharedColor
                {
                    SavedProjectId = projectId, ElementKey = c.ElementKey, Title = c.Title,
                    Icon = c.Icon, AttrValue = c.AttrValue, Value = c.Value,
                    IsSelected = c.IsSelected, Sort = c.Sort
                });
        }

        // Sync shared layers
        var sharedLayers = scenes.SelectMany(s => s.SharedLayers).DistinctBy(x => x.Key).ToList();
        if (sharedLayers.Count > 0)
        {
            var existingSL = await db.SavedSharedLayers
                .Where(x => x.SavedProjectId == projectId).ToListAsync();
            db.SavedSharedLayers.RemoveRange(existingSL);
            foreach (var l in sharedLayers)
                db.SavedSharedLayers.Add(MapSharedLayerEntity(projectId, l));
        }

        project.LastEditDate = DateTime.UtcNow;
        project.UpdatedAt = DateTime.UtcNow;

        // Recalc total duration
        project.ProjectDurationSec = scenes.Sum(s => s.SceneLengthSec - s.OverlapAtEndSec);

        await db.SaveChangesAsync();
        return await GetProjectAsync(projectId, userId);
    }

    // ── Mappers ───────────────────────────────────────────────────────────────

    private static SavedProjectSummaryResponse MapSummary(SavedProject p) => new(
        p.Id, p.UserId, p.OriginalProjectId, p.OriginalProjectName, p.OriginalContainerSlug,
        p.Name, p.Image, p.Type.ToString(), p.Resolution, p.ChooseMode,
        p.ProjectDurationSec, p.LastEditDate, p.CreatedAt);

    private static SavedProjectFullResponse MapFull(SavedProject p) => new(
        p.Id, p.UserId, p.OriginalProjectId, p.OriginalProjectName, p.OriginalContainerSlug,
        p.Name, p.Image, p.Type.ToString(), p.FrameRate, p.ProjectDurationSec,
        p.Resolution, p.ChooseMode, p.VipFactor,
        p.MusicFileId, p.MusicTrackId, p.MusicVolume,
        p.VoiceoverFileId, p.VoiceoverVolume, p.VoiceoverRecordedInBrowser,
        p.SfxVolume, p.SfxEnabled, p.AudioVisualizerMusicUrl, p.AudioVisualizerDurationSec,
        p.ManualColorPicker, p.SelectedPresetStoryId,
        p.LastEditStep, p.EditState, p.LastEditDate, p.CreatedAt,
        p.Scenes.Select(MapSceneResponse).ToList(),
        p.SharedColors.Select(MapSharedColorResponse).ToList(),
        p.SharedColorPresets.Select(MapSharedColorPresetResponse).ToList(),
        p.SharedLayers.Select(MapSharedLayerResponse).ToList()
    );

    private static SavedSceneResponse MapSceneResponse(SavedScene s) => new(
        s.Id, s.OriginalSceneId, s.Key, s.Title, s.Image, s.SceneType,
        s.Sort, s.SceneLengthSec, s.MinDurationSec, s.MaxDurationSec,
        s.OverlapAtEndSec, s.CanHandleDuration, s.ManualColorSelection, s.SelectedColorPresetId,
        s.Contents.Select(MapContentResponse).ToList(),
        s.Colors.Select(c => new SavedSceneColorResponse(c.Id, c.ElementKey, c.Title, c.Icon, c.AttrValue, c.Value, c.IsSelected, c.Sort)).ToList(),
        s.ColorPresets.Select(cp => new SavedSceneColorPresetResponse(cp.Id, cp.IsSelected, cp.Sort,
            cp.Items.Select(i => new SavedColorPresetItemResponse(i.Id, i.ElementKey, i.Value, i.Sort)).ToList()
        )).ToList(),
        s.Characters.Select(ch => new SavedSceneCharacterResponse(ch.Id, ch.Key, ch.Name, ch.Icon,
            ch.Controllers.Select(c => new SavedCharacterControllerResponse(c.Id, c.Name, c.Key, c.Value, c.Sort)).ToList()
        )).ToList()
    );

    private static SavedSceneContentResponse MapContentResponse(SavedSceneContent c) => new(
        c.Id, c.Key, c.Title, c.Type, c.Value, c.ValueFileId, c.FileUrlCached,
        c.FontFace, c.FontSize, c.Justify, c.PositionInContainer, c.DirectionLayerValue,
        c.IsTextBox, c.AiInputType, c.SelectedDp, c.RepeaterItemKey, c.RepeaterIndex,
        c.IsFocused, c.MappedList, c.Sort);

    private static SavedSharedColorResponse MapSharedColorResponse(SavedSharedColor c) =>
        new(c.Id, c.ElementKey, c.Title, c.Icon, c.AttrValue, c.Value, c.IsSelected, c.Sort);

    private static SavedSharedColorPresetResponse MapSharedColorPresetResponse(SavedSharedColorPreset cp) =>
        new(cp.Id, cp.Name, cp.IsSelected, cp.Sort,
            cp.Items.Select(i => new SavedColorPresetItemResponse(i.Id, i.ElementKey, i.Value, i.Sort)).ToList());

    private static SavedSharedLayerResponse MapSharedLayerResponse(SavedSharedLayer l) => new(
        l.Id, l.Key, l.Title, l.Type, l.Value, l.ValueFileId, l.FileUrlCached,
        l.FontFace, l.FontSize, l.Justify, l.PositionInContainer, l.DirectionLayerValue,
        l.IsTextBox, l.AiInputType, l.MappedList, l.Width, l.Height,
        l.IsFocused, l.IsFontChangeable, l.IsFontSizeChangeable, l.Sort);

    private static SavedSceneContent MapContentEntity(SaveSceneContentRequest c) => new()
    {
        Key = c.Key, Title = c.Title, Type = c.Type, Value = c.Value,
        ValueFileId = c.ValueFileId, InsertedFileType = c.InsertedFileType,
        FontFace = c.FontFace, FontFaceName = c.FontFaceName, FontSize = c.FontSize,
        DefaultFontSize = c.DefaultFontSize, DefaultFontFace = c.DefaultFontFace,
        Justify = c.Justify, PositionInContainer = c.PositionInContainer,
        DirectionLayerValue = c.DirectionLayerValue, IsTextBox = c.IsTextBox,
        AiInputType = c.AiInputType, SelectedDp = c.SelectedDp,
        RepeaterItemKey = c.RepeaterItemKey, RepeaterIndex = c.RepeaterIndex,
        IsFocused = c.IsFocused, MappedList = c.MappedList, Thumbnail = c.Thumbnail, Sort = c.Sort
    };

    private static SavedSharedLayer MapSharedLayerEntity(Guid projectId, SaveSharedLayerRequest l) => new()
    {
        SavedProjectId = projectId, Key = l.Key, Title = l.Title, Type = l.Type,
        Value = l.Value, ValueFileId = l.ValueFileId, FontFace = l.FontFace,
        FontFaceName = l.FontFaceName, FontSize = l.FontSize, Justify = l.Justify,
        PositionInContainer = l.PositionInContainer, DirectionLayerValue = l.DirectionLayerValue,
        IsTextBox = l.IsTextBox, AiInputType = l.AiInputType, MappedList = l.MappedList,
        Thumbnail = l.Thumbnail, Width = l.Width, Height = l.Height, IsFocused = l.IsFocused,
        IsFontChangeable = l.IsFontChangeable, IsFontSizeChangeable = l.IsFontSizeChangeable, Sort = l.Sort
    };
}