<?php

namespace App\Http\Controllers\Admin;

use App\Http\Controllers\Controller;
use App\Models\ResearchDirection;
use App\Models\Teacher;
use App\Support\ApiResponse;
use Illuminate\Http\JsonResponse;
use Illuminate\Http\Request;

class ResearchDirectionController extends Controller
{
    use ApiResponse;

    public function index(Request $request): JsonResponse
    {
        $query = ResearchDirection::query();

        if ($kw = $request->query('keyword')) {
            $query->where('name', 'like', "%{$kw}%");
        }
        if ($request->filled('status')) {
            $query->where('status', (int) $request->query('status'));
        }

        $paginator = $query
            ->orderBy('sort')
            ->orderBy('id')
            ->paginate((int) $request->query('page_size', 20))
            ->withQueryString();

        $paginator->getCollection()->transform(fn (ResearchDirection $r) => $this->serialize($r));

        return $this->paginated($paginator);
    }

    public function options(): JsonResponse
    {
        $items = ResearchDirection::query()
            ->where('status', 1)
            ->orderBy('sort')
            ->orderBy('name')
            ->get()
            ->map(fn (ResearchDirection $r) => $this->serialize($r));

        return $this->ok(['items' => $items]);
    }

    public function store(Request $request): JsonResponse
    {
        $data = $request->validate([
            'name' => ['required', 'string', 'max:255', 'unique:research_directions,name'],
            'sort' => ['nullable', 'integer', 'min:0'],
            'status' => ['required', 'integer', 'in:0,1'],
            'remark' => ['nullable', 'string', 'max:512'],
        ]);

        $row = ResearchDirection::query()->create([
            'name' => trim($data['name']),
            'sort' => (int) ($data['sort'] ?? 0),
            'status' => (int) $data['status'],
            'remark' => $data['remark'] ?? null,
        ]);

        return $this->ok($this->serialize($row), '已创建');
    }

    public function update(Request $request, int $researchDirection): JsonResponse
    {
        $row = ResearchDirection::query()->findOrFail($researchDirection);
        $data = $request->validate([
            'name' => ['sometimes', 'string', 'max:255', 'unique:research_directions,name,'.$row->id],
            'sort' => ['nullable', 'integer', 'min:0'],
            'status' => ['sometimes', 'integer', 'in:0,1'],
            'remark' => ['nullable', 'string', 'max:512'],
        ]);

        if (isset($data['name'])) {
            $data['name'] = trim($data['name']);
        }

        $row->fill($data);
        $row->save();

        return $this->ok($this->serialize($row->fresh()), '已保存');
    }

    public function destroy(int $researchDirection): JsonResponse
    {
        $row = ResearchDirection::query()->findOrFail($researchDirection);

        if ($row->adminUsers()->exists()) {
            return $this->fail('该研究方向已分配给网格员，无法删除', 422);
        }

        $row->delete();

        return $this->ok(null, '已删除');
    }

    /**
     * @return array<string, mixed>
     */
    protected function serialize(ResearchDirection $r): array
    {
        $teacherCount = $r->teachers()->count();

        return [
            'id' => $r->id,
            'name' => $r->name,
            'sort' => (int) $r->sort,
            'status' => (int) $r->status,
            'remark' => $r->remark,
            'teacher_count' => $teacherCount,
            'created_at' => $r->created_at?->toIso8601String(),
        ];
    }
}