<?php

namespace App\Http\Controllers\Api\Admin;

use App\Http\Controllers\Controller;
use App\Http\Requests\Admin\StoreFormSchemaDefinitionRequest;
use App\Http\Requests\Admin\UpdateFormSchemaDefinitionRequest;
use App\Models\Competition;
use App\Models\FormSchemaDefinition;
use Illuminate\Http\JsonResponse;
use Illuminate\Http\Request;
use Illuminate\Http\Response;

class FormSchemaDefinitionController extends Controller
{
    public function index(Request $request, Competition $competition): JsonResponse
    {
        $purpose = $request->query('purpose');
        $q = FormSchemaDefinition::query()->where('competition_id', $competition->id);
        if (in_array($purpose, [FormSchemaDefinition::PURPOSE_SIGNUP, FormSchemaDefinition::PURPOSE_REVIEW], true)) {
            $q->where('purpose', $purpose);
        }

        $rows = $q->orderByDesc('version')->orderByDesc('id')->get();

        return response()->json([
            'data' => $rows->map(fn (FormSchemaDefinition $s) => $this->toBrief($s, $competition))->values(),
        ]);
    }

    public function store(StoreFormSchemaDefinitionRequest $request, Competition $competition): JsonResponse
    {
        $purpose = $request->validated('purpose');
        $nextVersion = (int) FormSchemaDefinition::query()
            ->where('competition_id', $competition->id)
            ->where('purpose', $purpose)
            ->max('version') + 1;

        $schema = FormSchemaDefinition::query()->create([
            'competition_id' => $competition->id,
            'purpose' => $purpose,
            'name' => $request->validated('name'),
            'version' => $nextVersion,
            'schema_json' => $request->validated('schema_json'),
            'is_published' => (bool) $request->validated('is_published', false),
        ]);

        return response()->json($this->toDetail($schema, $competition), 201);
    }

    public function show(Competition $competition, FormSchemaDefinition $formSchema): JsonResponse
    {
        $this->assertSchemaBelongs($competition, $formSchema);

        return response()->json($this->toDetail($formSchema, $competition));
    }

    public function update(UpdateFormSchemaDefinitionRequest $request, Competition $competition, FormSchemaDefinition $formSchema): JsonResponse
    {
        $this->assertSchemaBelongs($competition, $formSchema);

        $formSchema->fill($request->validated());
        $formSchema->save();

        return response()->json($this->toDetail($formSchema->fresh(), $competition));
    }

    public function destroy(Competition $competition, FormSchemaDefinition $formSchema): Response
    {
        $this->assertSchemaBelongs($competition, $formSchema);

        if ((int) $competition->form_schema_id === $formSchema->id
            || (int) $competition->review_form_schema_id === $formSchema->id) {
            return response()->json([
                'message' => '该版本正被本场赛事使用，请先更换绑定后再删除。',
            ], 422);
        }

        $formSchema->delete();

        return response()->noContent();
    }

    private function assertSchemaBelongs(Competition $competition, FormSchemaDefinition $formSchema): void
    {
        if ((int) $formSchema->competition_id !== (int) $competition->id) {
            abort(404);
        }
    }

    /**
     * @return array<string, mixed>
     */
    private function toBrief(FormSchemaDefinition $s, Competition $competition): array
    {
        return [
            'id' => $s->id,
            'competition_id' => $s->competition_id,
            'purpose' => $s->purpose,
            'name' => $s->name,
            'version' => $s->version,
            'is_published' => $s->is_published,
            'is_current_signup' => (int) $competition->form_schema_id === (int) $s->id,
            'is_current_review' => (int) $competition->review_form_schema_id === (int) $s->id,
            'field_labels' => $this->extractFieldLabels($s->schema_json ?? []),
            'created_at' => $s->created_at?->toIso8601String(),
            'updated_at' => $s->updated_at?->toIso8601String(),
        ];
    }

    /**
     * @return array<string, mixed>
     */
    private function toDetail(FormSchemaDefinition $s, Competition $competition): array
    {
        $row = $this->toBrief($s, $competition);
        $row['schema_json'] = $s->schema_json ?? [];

        return $row;
    }

    /**
     * @param  array<int, mixed>  $schemaJson
     * @return array<int, string>
     */
    private function extractFieldLabels(array $schemaJson): array
    {
        $labels = [];
        foreach ($schemaJson as $item) {
            if (is_array($item) && isset($item['label']) && is_string($item['label']) && $item['label'] !== '') {
                $labels[] = $item['label'];
            }
            if (count($labels) >= 12) {
                break;
            }
        }

        return $labels;
    }
}