<?php

namespace Modules\Communication\Http\Controllers;

use App\User;
use Illuminate\Http\Request;
use Illuminate\Routing\Controller;
use Modules\Communication\Entities\ChatMessage;
use Modules\Communication\Entities\ChatRoom;
use Modules\Communication\Events\MessageSent;
use Modules\Communication\Events\UserTyping;
use Modules\Communication\Services\ChatRoomService;
use Modules\Communication\Services\PresenceService;

class ChatController extends Controller
{
    public function __construct(
        private ChatRoomService $chatRoomService,
        private PresenceService $presenceService
    ) {}

    private function authorizeModule(): int
    {
        $business_id = request()->session()->get('user.business_id');
        if (! auth()->user()->can('communication.access')) {
            abort(403, 'Unauthorized action.');
        }

        return (int) $business_id;
    }

    public function index()
    {
        $businessId = $this->authorizeModule();
        $this->presenceService->heartbeat($businessId, auth()->id());

        return view('communication::spa');
    }

    public function colleagues()
    {
        $businessId = $this->authorizeModule();
        $users = User::where('business_id', $businessId)
            ->where('id', '!=', auth()->id())
            ->orderBy('first_name')
            ->get(['id', 'surname', 'first_name', 'last_name', 'username', 'email']);

        $onlineIds = $this->presenceService->onlineUserIds($businessId, $users->pluck('id')->all());

        return response()->json($users->map(function ($user) use ($onlineIds) {
            return [
                'id' => $user->id,
                'surname' => $user->surname,
                'first_name' => $user->first_name,
                'last_name' => $user->last_name,
                'username' => $user->username,
                'email' => $user->email,
                'is_online' => in_array($user->id, $onlineIds, true),
            ];
        }));
    }

    public function presence()
    {
        $businessId = $this->authorizeModule();
        $userIds = User::where('business_id', $businessId)->pluck('id')->all();
        $onlineIds = $this->presenceService->onlineUserIds($businessId, $userIds);

        return response()->json(['online_user_ids' => $onlineIds]);
    }

    public function heartbeat()
    {
        $businessId = $this->authorizeModule();
        $this->presenceService->heartbeat($businessId, auth()->id());

        return response()->json(['success' => true]);
    }

    public function rooms(Request $request)
    {
        $businessId = $this->authorizeModule();
        $user = auth()->user();
        $this->presenceService->heartbeat($businessId, $user->id);

        $query = ChatRoom::where('business_id', $businessId)
            ->whereHas('members', fn ($q) => $q->where('users.id', $user->id))
            ->with([
                'members' => fn ($q) => $q->select('users.id', 'surname', 'first_name', 'last_name', 'username', 'email')->withPivot('last_read_at'),
                'latestMessage.user:id,surname,first_name,last_name,username',
            ]);

        if ($request->filled('type') && in_array($request->type, ['direct', 'group'], true)) {
            $query->where('type', $request->type);
        }

        if ($request->filled('q')) {
            $search = $request->q;
            $query->where(function ($sub) use ($search, $user) {
                $sub->where('name', 'like', '%'.$search.'%')
                    ->orWhereHas('members', function ($m) use ($search, $user) {
                        $m->where('users.id', '!=', $user->id)
                            ->where(function ($n) use ($search) {
                                $n->where('first_name', 'like', '%'.$search.'%')
                                    ->orWhere('last_name', 'like', '%'.$search.'%');
                            });
                    })
                    ->orWhereHas('latestMessage', fn ($lm) => $lm->where('body', 'like', '%'.$search.'%'));
            });
        }

        $rooms = $query->orderByDesc('last_message_at')
            ->orderByDesc('updated_at')
            ->get();

        $memberIds = $rooms->flatMap(fn ($room) => $room->members->pluck('id'))->unique()->all();
        $onlineIds = $this->presenceService->onlineUserIds($businessId, $memberIds);

        return response()->json($rooms->map(function ($room) use ($user, $onlineIds) {
            $myPivot = $room->members->firstWhere('id', $user->id)?->pivot;
            $lastReadAt = $myPivot?->last_read_at;
            $unread = 0;
            if ($room->latestMessage && (int) $room->latestMessage->user_id !== (int) $user->id) {
                if (! $lastReadAt || $room->latestMessage->created_at > $lastReadAt) {
                    $unread = ChatMessage::where('chat_room_id', $room->id)
                        ->when($lastReadAt, fn ($q) => $q->where('created_at', '>', $lastReadAt))
                        ->where('user_id', '!=', $user->id)
                        ->count();
                }
            }

            $otherMember = $room->type === 'direct'
                ? $room->members->firstWhere('id', '!=', $user->id)
                : null;

            return [
                'id' => $room->id,
                'type' => $room->type,
                'name' => $room->name,
                'created_by' => $room->created_by,
                'last_message_at' => $room->last_message_at?->toIso8601String(),
                'members' => $room->members->map(fn ($m) => [
                    'id' => $m->id,
                    'surname' => $m->surname,
                    'first_name' => $m->first_name,
                    'last_name' => $m->last_name,
                    'username' => $m->username,
                    'email' => $m->email,
                    'is_online' => in_array($m->id, $onlineIds, true),
                ]),
                'latest_message' => $room->latestMessage ? [
                    'body' => $room->latestMessage->body,
                    'created_at' => $room->latestMessage->created_at?->toIso8601String(),
                    'user' => $room->latestMessage->user,
                ] : null,
                'unread_count' => $unread,
                'is_other_online' => $otherMember ? in_array($otherMember->id, $onlineIds, true) : false,
            ];
        }));
    }

    public function showRoom(int $roomId)
    {
        $businessId = $this->authorizeModule();
        $room = ChatRoom::where('business_id', $businessId)
            ->with(['members:id,surname,first_name,last_name,username,email', 'creator:id,surname,first_name,last_name,username'])
            ->findOrFail($roomId);
        $this->chatRoomService->assertRoomMember($room, auth()->user());

        $onlineIds = $this->presenceService->onlineUserIds(
            $businessId,
            $room->members->pluck('id')->all()
        );

        return response()->json([
            'id' => $room->id,
            'type' => $room->type,
            'name' => $room->name,
            'created_by' => $room->created_by,
            'members' => $room->members->map(fn ($m) => [
                'id' => $m->id,
                'surname' => $m->surname,
                'first_name' => $m->first_name,
                'last_name' => $m->last_name,
                'username' => $m->username,
                'email' => $m->email,
                'is_online' => in_array($m->id, $onlineIds, true),
            ]),
        ]);
    }

    public function createRoom(Request $request)
    {
        $businessId = $this->authorizeModule();
        $validated = $request->validate([
            'type' => 'required|in:direct,group',
            'user_id' => 'required_if:type,direct|integer|exists:users,id',
            'name' => 'required_if:type,group|string|max:255',
            'member_ids' => 'required_if:type,group|array|min:1',
            'member_ids.*' => 'integer|exists:users,id',
        ]);

        $user = auth()->user();
        $room = $validated['type'] === 'direct'
            ? $this->chatRoomService->findOrCreateDirectRoom($businessId, $user, (int) $validated['user_id'])
            : $this->chatRoomService->createGroupRoom($businessId, $user, $validated['name'], $validated['member_ids'] ?? []);

        return response()->json($room);
    }

    public function addMember(Request $request, int $roomId)
    {
        $businessId = $this->authorizeModule();
        $validated = $request->validate(['user_id' => 'required|integer|exists:users,id']);
        $room = ChatRoom::where('business_id', $businessId)->findOrFail($roomId);
        $room = $this->chatRoomService->addMember($room, $businessId, auth()->user(), (int) $validated['user_id']);

        return response()->json($room);
    }

    public function removeMember(int $roomId, int $userId)
    {
        $businessId = $this->authorizeModule();
        $room = ChatRoom::where('business_id', $businessId)->findOrFail($roomId);
        $room = $this->chatRoomService->removeMember($room, auth()->user(), $userId);

        return response()->json($room);
    }

    public function messages(Request $request, int $roomId)
    {
        $businessId = $this->authorizeModule();
        $room = ChatRoom::where('business_id', $businessId)->findOrFail($roomId);
        $this->chatRoomService->assertRoomMember($room, auth()->user());

        $query = ChatMessage::where('chat_room_id', $room->id)
            ->with('user:id,surname,first_name,last_name,username,email')
            ->orderBy('created_at');

        if ($request->filled('search')) {
            $query->where('body', 'like', '%'.$request->search.'%');
        }

        return response()->json($query->get());
    }

    public function sendMessage(Request $request, int $roomId)
    {
        $businessId = $this->authorizeModule();
        $validated = $request->validate([
            'body' => 'required|string|max:5000',
            'type' => 'sometimes|in:text,file,image',
            'metadata' => 'sometimes|array',
        ]);
        $room = ChatRoom::where('business_id', $businessId)->findOrFail($roomId);
        $this->chatRoomService->assertRoomMember($room, auth()->user());

        $message = ChatMessage::create([
            'chat_room_id' => $room->id,
            'user_id' => auth()->id(),
            'body' => $validated['body'],
            'type' => $validated['type'] ?? 'text',
            'metadata' => $validated['metadata'] ?? null,
        ]);
        $room->update(['last_message_at' => now()]);
        $this->presenceService->heartbeat($businessId, auth()->id());
        try {
            event(new MessageSent($message->load('user:id,surname,first_name,last_name,username,email'), $businessId));
        } catch (\Throwable $e) {
            report($e);
        }

        return response()->json($message->load('user:id,surname,first_name,last_name,username,email'));
    }

    public function markRead(int $roomId)
    {
        $businessId = $this->authorizeModule();
        $room = ChatRoom::where('business_id', $businessId)->findOrFail($roomId);
        $this->chatRoomService->assertRoomMember($room, auth()->user());
        $room->members()->updateExistingPivot(auth()->id(), ['last_read_at' => now()]);

        return response()->json(['success' => true]);
    }

    public function typing(int $roomId)
    {
        $businessId = $this->authorizeModule();
        $room = ChatRoom::where('business_id', $businessId)->findOrFail($roomId);
        $this->chatRoomService->assertRoomMember($room, auth()->user());
        try {
            event(new UserTyping($businessId, $room->id, auth()->id(), auth()->user()->user_full_name));
        } catch (\Throwable $e) {
            report($e);
        }

        return response()->json(['success' => true]);
    }
}