<?php

namespace App\Http\Controllers;

use App\Http\Requests\SongRequest;
use App\Models\Label;
use App\Models\Song;
use App\Services\SongService;
use Illuminate\Http\JsonResponse;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\DB;

class SongController extends Controller
{
    public function __construct(
        private readonly SongService $songService,
    ) {}

    public function index(Request $request): JsonResponse
    {
        $query = Song::query()
            ->withCount(['sections as content_slides_count' => fn ($q) => $q->has('slides')]);

        if ($search = $request->input('search')) {
            $query->where(function ($q) use ($search) {
                $q->where('title', 'like', "%{$search}%")
                    ->orWhere('ccli_id', 'like', "%{$search}%");
            });
        }

        // The SongDB UI sends with_content=1 by default to hide songs without content;
        // pass with_content=0 (or omit) to include empty songs.
        if ($request->boolean('with_content')) {
            $query->whereHas('sections', fn ($q) => $q->has('slides'));
        }

        $songs = $query->orderBy('title')
            ->paginate($request->input('per_page', 20));

        return response()->json([
            'data' => $songs->map(fn (Song $song) => [
                'id' => $song->id,
                'title' => $song->title,
                'ccli_id' => $song->ccli_id,
                'author' => $song->author,
                'has_translation' => $song->has_translation,
                'has_content' => (int) $song->content_slides_count > 0,
                'last_used_at' => $song->last_used_at?->toDateString(),
                'last_used_in_service' => $song->last_used_in_service,
                'created_at' => $song->created_at->toDateTimeString(),
                'updated_at' => $song->updated_at->toDateTimeString(),
            ]),
            'meta' => [
                'current_page' => $songs->currentPage(),
                'last_page' => $songs->lastPage(),
                'per_page' => $songs->perPage(),
                'total' => $songs->total(),
            ],
        ]);
    }

    public function store(SongRequest $request): JsonResponse
    {
        $song = DB::transaction(function () use ($request) {
            $song = Song::create($request->validated());

            $this->songService->createDefaultArrangement($song);

            return $song;
        });

        return response()->json([
            'message' => 'Song erfolgreich erstellt',
            'data' => $this->formatSongDetail($song->fresh(['arrangements.arrangementSections.section.slides', 'arrangements.arrangementSections.section.label'])),
        ], 201);
    }

    public function show(int $id): JsonResponse
    {
        $song = Song::with(['arrangements.arrangementSections.section.slides', 'arrangements.arrangementSections.section.label'])->find($id);

        if (! $song) {
            return response()->json(['message' => 'Song nicht gefunden'], 404);
        }

        return response()->json([
            'data' => $this->formatSongDetail($song),
        ]);
    }

    public function update(SongRequest $request, int $id): JsonResponse
    {
        $song = Song::find($id);

        if (! $song) {
            return response()->json(['message' => 'Song nicht gefunden'], 404);
        }

        $song->update($request->validated());

        return response()->json([
            'message' => 'Song erfolgreich aktualisiert',
            'data' => $this->formatSongDetail($song->fresh(['arrangements.arrangementSections.section.slides', 'arrangements.arrangementSections.section.label'])),
        ]);
    }

    public function destroy(int $id): JsonResponse
    {
        $song = Song::find($id);

        if (! $song) {
            return response()->json(['message' => 'Song nicht gefunden'], 404);
        }

        $song->delete();

        return response()->json([
            'message' => 'Song erfolgreich gelöscht',
        ]);
    }

    public function formatSongDetail(Song $song): array
    {
        $defaultArr = $song->arrangements->firstWhere('is_default', true);

        $groupsPayload = [];
        if ($defaultArr !== null) {
            $groupsPayload = $defaultArr->arrangementSections
                ->sortBy('order')
                ->values()
                ->map(fn ($arrangementSection) => [
                    'id' => $arrangementSection->section?->id,
                    'section_id' => $arrangementSection->section?->id,
                    'label_id' => $arrangementSection->section?->label_id,
                    'name' => $arrangementSection->section?->label?->name,
                    'color' => $arrangementSection->section?->label?->color,
                    'order' => $arrangementSection->order,
                    'slides' => $arrangementSection->section
                        ? $arrangementSection->section->slides
                            ->sortBy('order')
                            ->values()
                            ->map(fn ($slide) => [
                                'id' => $slide->id,
                                'order' => $slide->order,
                                'text_content' => $slide->text_content,
                                'text_content_translated' => $slide->text_content_translated,
                                'notes' => $slide->notes,
                            ])->toArray()
                        : [],
                ])->toArray();
        }

        return [
            'id' => $song->id,
            'title' => $song->title,
            'ccli_id' => $song->ccli_id,
            'author' => $song->author,
            'copyright_text' => $song->copyright_text,
            'copyright_year' => $song->copyright_year,
            'publisher' => $song->publisher,
            'has_translation' => $song->has_translation,
            'last_used_at' => $song->last_used_at?->toDateString(),
            'last_used_in_service' => $song->last_used_in_service,
            'created_at' => $song->created_at->toDateTimeString(),
            'updated_at' => $song->updated_at->toDateTimeString(),
            'groups' => $groupsPayload,
            'available_labels' => Label::query()
                ->whereNull('hidden_at')
                ->orderBy('name')
                ->get(['id', 'name', 'color'])
                ->map(fn (Label $label) => [
                    'id' => $label->id,
                    'name' => $label->name,
                    'color' => $label->color,
                ])->toArray(),
            'arrangements' => $song->arrangements->map(fn ($arr) => [
                'id' => $arr->id,
                'name' => $arr->name,
                'is_default' => $arr->is_default,
                'arrangement_groups' => $arr->arrangementSections->sortBy('order')->values()->map(fn ($arrangementSection) => [
                    'id' => $arrangementSection->id,
                    'section_id' => $arrangementSection->song_section_id,
                    'label_id' => $arrangementSection->section?->label_id,
                    'order' => $arrangementSection->order,
                ])->toArray(),
            ])->toArray(),
        ];
    }
}