<?php

namespace App\Http\Controllers;

use App\Models\ChatMessage;
use App\Models\ChatMessageReaction;
use App\Models\ChatMessageReport;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\DB;

class ChatController extends Controller
{
    private function formatMessage(ChatMessage $m, int $authId = 0): array
    {
        $user = $m->user;
        $reactionsAgg = [];

        foreach ($m->reactions->groupBy('emoji') as $emoji => $group) {
            $reactionsAgg[] = [
                'emoji'       => $emoji,
                'count'       => $group->count(),
                'reactedByMe' => $group->contains('user_id', $authId),
            ];
        }

        $replyTo = null;
        if ($m->reply_to_id && $m->replyTo) {
            $replyTo = [
                'id'      => $m->replyTo->id,
                'message' => $m->replyTo->message,
                'user'    => [
                    'id'       => $m->replyTo->user?->id,
                    'username' => $m->replyTo->user?->username,
                ],
            ];
        }

        return [
            'id'           => $m->id,
            'user_id'      => $m->user_id,
            'message'      => $m->is_deleted ? null : $m->message,
            'is_deleted'   => (bool) $m->is_deleted,
            'deleted_by_user' => $m->is_deleted && $m->deletedByUser ? [
                'id'       => $m->deletedByUser->id,
                'username' => $m->deletedByUser->username,
                'role'     => $m->deletedByUser->role ?? 'user',
            ] : null,
            'reply_to_id'  => $m->reply_to_id,
            'reply_to'     => $replyTo,
            'created_at'   => $m->created_at?->toIso8601String(),
            'user'         => [
                'id'        => $user?->id,
                'username'  => $user?->username,
                'avatar_url' => $user?->avatar_url ?? $user?->avatar ?? null,
                'role'      => $user?->role ?? 'user',
                'vip_level' => (int) ($user?->vip_level ?? 0),
                'clan_tag'  => $user?->clan_tag ?? null,
            ],
            'reactions_agg' => $reactionsAgg,
        ];
    }

    /**
     * List recent chat messages from local DB.
     */
    public function index(Request $request)
    {
        $limit   = min(max((int) $request->query('limit', 50), 1), 200);
        $afterId = $request->query('after_id');
        $authId  = (int) optional($request->user())->id;

        $query = ChatMessage::with([
            'user:id,username,avatar,avatar_url,role,vip_level,clan_tag',
            'reactions',
            'replyTo:id,message,user_id',
            'replyTo.user:id,username',
            'deletedByUser:id,username,role',
        ])->orderBy('id', 'asc');

        if ($afterId !== null) {
            $query->where('id', '>', (int) $afterId);
        } else {
            // Return last N messages
            $query = ChatMessage::with([
                'user:id,username,avatar,avatar_url,role,vip_level,clan_tag',
                'reactions',
                'replyTo:id,message,user_id',
                'replyTo.user:id,username',
            ])->orderBy('id', 'desc')->limit($limit);

            $messages = $query->get()->reverse()->values();
            $formatted = $messages->map(fn ($m) => $this->formatMessage($m, $authId))->values()->all();
            $lastId = $messages->last()?->id;

            return response()->json(['data' => $formatted, 'last_id' => $lastId]);
        }

        $messages  = $query->limit($limit)->get();
        $formatted = $messages->map(fn ($m) => $this->formatMessage($m, $authId))->values()->all();
        $lastId    = $messages->last()?->id;

        return response()->json(['data' => $formatted, 'last_id' => $lastId]);
    }

    /**
     * Store a new chat message in local DB.
     */
    public function store(Request $request)
    {
        $user = $request->user();
        if (!$user) return response()->json(['message' => 'Unauthenticated'], 401);

        $validated = $request->validate([
            'message'     => ['required', 'string', 'min:1', 'max:300'],
            'reply_to_id' => ['nullable', 'integer', 'exists:chat_messages,id'],
        ]);

        // Check local chat ban
        $chatBan = \App\Models\UserRestriction::where('user_id', $user->id)
            ->where('type', 'chat_ban')
            ->where('active', true)
            ->where(fn($q) => $q->whereNull('ends_at')->orWhere('ends_at', '>', now()))
            ->first();
        if ($chatBan) {
            return response()->json([
                'message' => 'Du bist vom Chat gebannt.',
                'type'    => 'chat_ban',
                'ends_at' => $chatBan->ends_at?->toIso8601String(),
            ], 403);
        }

        $msg = ChatMessage::create([
            'user_id'     => $user->id,
            'message'     => $validated['message'],
            'reply_to_id' => $validated['reply_to_id'] ?? null,
        ]);

        $msg->load([
            'user:id,username,avatar,avatar_url,role,vip_level,clan_tag',
            'reactions',
            'replyTo:id,message,user_id',
            'replyTo.user:id,username',
            'deletedByUser:id,username,role',
        ]);

        return response()->json(['data' => $this->formatMessage($msg, (int) $user->id)], 201);
    }

    /**
     * Soft-delete a chat message (admin/mod only).
     */
    public function destroy(Request $request, int $id)
    {
        $user = $request->user();
        if (!$user) return response()->json(['message' => 'Unauthenticated'], 401);

        $role = strtolower((string) $user->role);
        if (!in_array($role, ['admin', 'moderator', 'mod'])) {
            return response()->json(['message' => 'Forbidden'], 403);
        }

        $msg = ChatMessage::findOrFail($id);
        $msg->update(['is_deleted' => true, 'deleted_by' => $user->id]);

        $msg->load([
            'user:id,username,avatar,avatar_url,role,vip_level,clan_tag',
            'reactions',
            'replyTo:id,message,user_id',
            'replyTo.user:id,username',
            'deletedByUser:id,username,role',
        ]);

        return response()->json(['data' => $this->formatMessage($msg, (int) $user->id)]);
    }

    /**
     * Toggle a reaction on a message.
     */
    public function react(Request $request, int $id)
    {
        $user = $request->user();
        if (!$user) return response()->json(['message' => 'Unauthenticated'], 401);

        $validated = $request->validate([
            'emoji' => ['required', 'string', 'max:8'],
        ]);

        $msg = ChatMessage::findOrFail($id);

        $existing = ChatMessageReaction::where([
            'message_id' => $msg->id,
            'user_id'    => $user->id,
            'emoji'      => $validated['emoji'],
        ])->first();

        if ($existing) {
            $existing->delete();
        } else {
            ChatMessageReaction::create([
                'message_id' => $msg->id,
                'user_id'    => $user->id,
                'emoji'      => $validated['emoji'],
            ]);
        }

        $msg->load([
            'user:id,username,avatar,avatar_url,role,vip_level,clan_tag',
            'reactions',
            'replyTo:id,message,user_id',
            'replyTo.user:id,username',
            'deletedByUser:id,username,role',
        ]);

        return response()->json(['data' => $this->formatMessage($msg, (int) $user->id)]);
    }

    /**
     * Report a chat message.
     */
    public function report(Request $request, int $id)
    {
        $user = $request->user();
        if (!$user) return response()->json(['message' => 'Unauthenticated'], 401);

        $validated = $request->validate([
            'message_text'     => ['required', 'string', 'max:500'],
            'sender_id'        => ['nullable', 'integer'],
            'sender_username'  => ['nullable', 'string', 'max:255'],
            'reason'           => ['nullable', 'string', 'max:255'],
            'context_messages' => ['nullable', 'array'],
            'context_messages.*.id'         => ['nullable'],
            'context_messages.*.message'    => ['nullable', 'string', 'max:500'],
            'context_messages.*.user'       => ['nullable', 'array'],
            'context_messages.*.created_at' => ['nullable', 'string'],
        ]);

        ChatMessageReport::create([
            'reporter_id'      => $user->id,
            'message_id'       => (string) $id,
            'message_text'     => $validated['message_text'],
            'sender_id'        => $validated['sender_id'] ?? null,
            'sender_username'  => $validated['sender_username'] ?? null,
            'reason'           => $validated['reason'] ?? null,
            'context_messages' => $validated['context_messages'] ?? null,
        ]);

        return response()->json(['message' => 'Reported.'], 201);
    }
}