<?php

namespace App\Http\Controllers\Api\Admin\OsManager;

use App\Http\Controllers\Controller;
use App\Models\OsGroup;
use Illuminate\Http\JsonResponse;
use Illuminate\Http\Request;

class OsGroupController extends Controller
{
    /**
     * List all OS groups with their OS entries.
     * Supports ?all=true for full list (no pagination).
     */
    public function index(Request $request): JsonResponse
    {
        $query = OsGroup::withCount('os')
            ->with(['os' => fn($q) => $q->with('host.datacenter.vCenter')->orderBy('version')])
            ->when(
                $request->get('filter'),
                fn($q, $f) => $q->where('name', 'like', "%{$f}%")
            )
            ->orderBy('name');

        if ($request->boolean('all')) {
            $items = $query->get();

            return response()->json([
                'error' => false,
                'data'  => $items->map(fn($g) => $this->formatGroup($g)),
            ]);
        }

        $perPage   = min((int) $request->get('per_page', 15), 100);
        $paginator = $query->paginate($perPage);

        return response()->json([
            'error' => false,
            'data'  => [
                'items'        => collect($paginator->items())->map(fn($g) => $this->formatGroup($g)),
                'total'        => $paginator->total(),
                'per_page'     => $paginator->perPage(),
                'current_page' => $paginator->currentPage(),
                'last_page'    => $paginator->lastPage(),
            ],
        ]);
    }

    public function show(int $id): JsonResponse
    {
        $group = OsGroup::withCount('os')
            ->with(['os' => fn($q) => $q->with('host.datacenter.vCenter')->orderBy('version')])
            ->find($id);

        if (! $group) {
            return response()->json(['error' => true, 'message' => 'Không tìm thấy nhóm OS.'], 404);
        }

        return response()->json(['error' => false, 'data' => $this->formatGroup($group)]);
    }

    public function store(Request $request): JsonResponse
    {
        $validated = $request->validate([
            'name'      => 'required|string|max:255',
            'is_active' => 'boolean',
        ]);

        $group = OsGroup::create([
            'name'   => $validated['name'],
            'status' => ($validated['is_active'] ?? true) ? 1 : 0,
        ]);

        return response()->json([
            'error'   => false,
            'message' => 'Tạo nhóm OS thành công.',
            'data'    => $this->formatGroup($group->load('os')),
        ], 201);
    }

    public function update(Request $request, int $id): JsonResponse
    {
        $group = OsGroup::find($id);

        if (! $group) {
            return response()->json(['error' => true, 'message' => 'Không tìm thấy nhóm OS.'], 404);
        }

        $validated = $request->validate([
            'name'      => 'sometimes|required|string|max:255',
            'is_active' => 'boolean',
        ]);

        $group->update([
            'name'   => $validated['name'] ?? $group->name,
            'status' => isset($validated['is_active']) ? ($validated['is_active'] ? 1 : 0) : $group->status,
        ]);

        return response()->json([
            'error'   => false,
            'message' => 'Cập nhật nhóm OS thành công.',
            'data'    => $this->formatGroup($group->fresh(['os'])),
        ]);
    }

    public function destroy(int $id): JsonResponse
    {
        $group = OsGroup::withCount('os')->find($id);

        if (! $group) {
            return response()->json(['error' => true, 'message' => 'Không tìm thấy nhóm OS.'], 404);
        }

        if ($group->os_count > 0) {
            return response()->json([
                'error'   => true,
                'message' => "Không thể xoá nhóm đang chứa {$group->os_count} OS. Hãy xoá các OS trước.",
            ], 422);
        }

        $group->delete();

        return response()->json(['error' => false, 'message' => 'Xoá nhóm OS thành công.']);
    }

    // ── helpers ──────────────────────────────────────────────────────────────

    private function formatGroup(OsGroup $group): array
    {
        return [
            'id'        => $group->id,
            'name'      => $group->name,
            'is_active' => (bool) $group->status,
            'os_count'  => $group->os_count ?? $group->os->count(),
            'os_list'   => $group->relationLoaded('os')
                ? $group->os->map(fn($o) => $this->formatOs($o))->values()
                : [],
        ];
    }

    private function formatOs(\App\Models\Os $os): array
    {
        $host = $os->relationLoaded('host') ? $os->host : null;

        return [
            'id'              => $os->id,
            'version'         => $os->version,
            'template_id'     => $os->template_id,
            'is_active'       => (bool) $os->status,
            'os_group_id'     => $os->os_group_id,
            'module_host_id'  => $os->module_host_id,
            'host_name'       => $host?->name,
            'datacenter_name' => $host?->datacenter?->name,
            'vcenter_name'    => $host?->datacenter?->vCenter?->host,
        ];
    }
}