<?php

namespace App\Http\Controllers;

use Illuminate\Http\Request;
use Illuminate\Support\Facades\Auth;
use Illuminate\Support\Facades\Http;
use Illuminate\Support\Str;
use Symfony\Component\HttpFoundation\StreamedResponse;

class SupportChatController extends Controller
{
    private const SESSION_KEY = 'support_chat';

    private function ensureEnabled()
    {
        // Use config/env directly to avoid cache/DB dependency if possible,
        // or assume cache is file-based (which is fine).
        $flag = cache()->get('support_chat_enabled');
        $enabled = is_null($flag) ? (bool) config('app.support_chat_enabled', env('SUPPORT_CHAT_ENABLED', true)) : (bool) $flag;
        if (!$enabled) {
            abort(503, 'Support chat is currently unavailable.');
        }
    }

    private function isChatEnabled(): bool
    {
        $flag = cache()->get('support_chat_enabled');
        return is_null($flag) ? (bool) config('app.support_chat_enabled', env('SUPPORT_CHAT_ENABLED', true)) : (bool) $flag;
    }

    private function sessionState(Request $request): array
    {
        $state = $request->session()->get(self::SESSION_KEY, [
            'thread_id' => null,
            'status' => 'new',
            'topic' => null,
            'messages' => [],
            'data_access_granted' => false,
        ]);

        if (!empty($state['thread_id'])) {
            $cached = cache()->get('support_threads:'.$state['thread_id']);
            if (is_array($cached)) {
                $state['status'] = $cached['status'] ?? $state['status'];
                foreach ($cached['messages'] ?? [] as $msg) {
                    if (($msg['sender'] ?? '') === 'agent') {
                        $state['status'] = 'agent';
                        break;
                    }
                }
                if (count($cached['messages'] ?? []) > count($state['messages'])) {
                    $state['messages'] = $cached['messages'];
                }
            }
        }
        return $state;
    }

    private function saveState(Request $request, array $state): void
    {
        $state['messages'] = array_slice($state['messages'], -100);
        $state['updated_at'] = now()->toIso8601String();
        $request->session()->put(self::SESSION_KEY, $state);
        $this->persistThread($request, $state);
    }

    private function persistThread(Request $request, array $state): void
    {
        if (empty($state['thread_id'])) return;
        $user = $request->user();

        // Construct user data safely without assuming local DB columns exist if Auth is mocked
        $userData = null;
        if ($user) {
            $userData = [
                'id' => $user->id ?? 'guest',
                'username' => $user->username ?? $user->name ?? 'Guest',
                'email' => $user->email ?? '',
                'avatar_url' => $user->avatar_url ?? $user->profile_photo_url ?? null,
            ];
        }

        $record = [
            'id' => $state['thread_id'],
            'status' => $state['status'] ?? 'new',
            'topic' => $state['topic'] ?? null,
            'user' => $userData,
            'messages' => $state['messages'] ?? [],
            'updated_at' => now()->toIso8601String(),
        ];

        // Cache is file/redis based, so this is fine (no SQL DB)
        cache()->put('support_threads:'.$state['thread_id'], $record, now()->addDay());

        $index = cache()->get('support_threads_index', []);
        $found = false;
        foreach ($index as &$row) {
            if (($row['id'] ?? null) === $record['id']) {
                $row['updated_at'] = $record['updated_at'];
                $row['status'] = $record['status'];
                $row['topic'] = $record['topic'];
                $row['user'] = $record['user'];
                $found = true;
                break;
            }
        }
        if (!$found) {
            $index[] = [
                'id' => $record['id'],
                'updated_at' => $record['updated_at'],
                'status' => $record['status'],
                'topic' => $record['topic'],
                'user' => $record['user'],
            ];
        }
        cache()->put('support_threads_index', $index, now()->addDay());
    }

    public function start(Request $request)
    {
        // ensureEnabled removed here to allow handoff logic
        $user = $request->user();
        abort_unless($user, 401);

        $data = $request->validate(['topic' => 'nullable|string|max:60']);
        $enabled = $this->isChatEnabled();

        $state = $this->sessionState($request);
        if (!$state['thread_id']) {
            $state['thread_id'] = (string) Str::uuid();
            $state['status'] = $enabled ? 'ai' : 'handoff';
            $state['topic'] = $data['topic'] ?? null;
            $state['messages'] = [];
            $state['data_access_granted'] = false;
            $state['user'] = [
                'id' => $user->id,
                'username' => $user->username ?? $user->name,
                'email' => $user->email
            ];

            if (!empty($data['topic'])) {
                 $state['messages'][] = ['id' => Str::uuid()->toString(), 'sender' => 'user', 'body' => 'Thema gewählt: ' . $data['topic'], 'at' => now()->toIso8601String()];

                 if ($enabled) {
                    $aiReply = $this->askOllama($state);
                    if ($aiReply) {
                        $state['messages'][] = ['id' => Str::uuid()->toString(), 'sender' => 'ai', 'body' => $aiReply, 'at' => now()->toIso8601String()];
                    } else {
                        // Ollama offline or returned nothing — fall back to human handoff
                        $state['status'] = 'handoff';
                        $state['messages'][] = ['id' => Str::uuid()->toString(), 'sender' => 'system', 'body' => 'Unser KI-Assistent ist gerade nicht erreichbar. Ein Mitarbeiter wird sich in Kürze bei dir melden.', 'at' => now()->toIso8601String()];
                    }
                 } else {
                     $state['messages'][] = ['id' => Str::uuid()->toString(), 'sender' => 'system', 'body' => 'Der KI-Assistent ist derzeit inaktiv. Ein Mitarbeiter wird sich in Kürze bei dir melden.', 'at' => now()->toIso8601String()];
                 }
            }
        }

        $this->saveState($request, $state);
        return response()->json($state);
    }

    public function close(Request $request)
    {
        abort_unless(Auth::check(), 401);
        $state = $this->sessionState($request);

        if (!empty($state['thread_id'])) {
            cache()->forget('support_threads:'.$state['thread_id']);
            $index = cache()->get('support_threads_index', []);
            $index = array_filter($index, fn($item) => $item['id'] !== $state['thread_id']);
            cache()->put('support_threads_index', array_values($index), now()->addDay());
        }

        $request->session()->forget(self::SESSION_KEY);

        return response()->json(['thread_id' => null, 'status' => 'closed', 'topic' => null, 'messages' => []]);
    }

    public function message(Request $request)
    {
        $user = $request->user();
        abort_unless($user, 401);

        $data = $request->validate(['text' => 'required|string|min:1|max:1000']);
        $text = trim($data['text']);
        $state = $this->sessionState($request);
        $enabled = $this->isChatEnabled();

        if (!$state['thread_id'] || ($state['status'] ?? null) === 'closed') {
            return response()->json(['error' => 'No active chat thread.'], 422);
        }

        $state['messages'][] = ['id' => Str::uuid()->toString(), 'sender' => 'user', 'body' => $text, 'at' => now()->toIso8601String()];

        if (!$enabled) {
            $lastMsg = collect($state['messages'])->where('sender', 'system')->last();
            if (!$lastMsg || !Str::contains($lastMsg['body'], 'Mitarbeiter')) {
                 $state['status'] = 'handoff';
                 $state['messages'][] = ['id' => Str::uuid()->toString(), 'sender' => 'system', 'body' => 'Deine Nachricht wurde empfangen. Bitte warte auf einen Mitarbeiter.', 'at' => now()->toIso8601String()];
            }
            $this->saveState($request, $state);
            return response()->json($state);
        }

        if (Str::of(Str::lower($text))->contains(['ja', 'yes', 'erlaubt', 'okay', 'ok', 'zugriff'])) {
            $lastSystemMsg = collect($state['messages'])->where('sender', 'system')->last();
            if ($lastSystemMsg && Str::contains($lastSystemMsg['body'], 'zugreifen')) {
                $state['data_access_granted'] = true;
                $state['messages'][] = ['id' => Str::uuid()->toString(), 'sender' => 'system', 'body' => 'Zugriff erlaubt. Ich sehe mir deine Daten an...', 'at' => now()->toIso8601String()];
                $aiReply = $this->askOllama($state);
                if ($aiReply) {
                    $state['messages'][] = ['id' => Str::uuid()->toString(), 'sender' => 'ai', 'body' => $aiReply, 'at' => now()->toIso8601String()];
                }
                $this->saveState($request, $state);
                return response()->json($state);
            }
        }

        if (Str::contains($text, ['🛑', ':stop:', 'STOP'])) {
            $state['status'] = 'stopped';
            $state['messages'][] = ['id' => Str::uuid()->toString(), 'sender' => 'system', 'body' => 'Verstanden. Soll ein Mitarbeiter übernehmen?', 'at' => now()->toIso8601String()];
            $this->saveState($request, $state);
            return response()->json($state);
        }

        if ($state['status'] === 'stopped' && Str::of(Str::lower($text))->contains(['ja', 'yes', 'y'])) {
            return $this->handoff($request);
        }

        if (in_array($state['status'], ['handoff', 'agent'])) {
            $this->saveState($request, $state);
            return response()->json($state);
        }

        $aiReply = $this->askOllama($state);

        if ($aiReply && (str_contains($aiReply, '[HANDOFF]') || trim($aiReply) === '[HANDOFF]')) {
            return $this->handoff($request);
        }

        if ($aiReply && (str_contains($aiReply, '[REQUEST_DATA]') || trim($aiReply) === '[REQUEST_DATA]')) {
             $state['messages'][] = ['id' => Str::uuid()->toString(), 'sender' => 'system', 'body' => 'Um dir besser helfen zu können, müsste ich auf deine Kontodaten (Wallet, Boni, etc.) zugreifen. Ist das in Ordnung? (Antworte mit "Ja")', 'at' => now()->toIso8601String()];
             $this->saveState($request, $state);
             return response()->json($state);
        }

        if ($aiReply) {
            $state['messages'][] = ['id' => Str::uuid()->toString(), 'sender' => 'ai', 'body' => $aiReply, 'at' => now()->toIso8601String()];
        } else {
            $state['messages'][] = ['id' => Str::uuid()->toString(), 'sender' => 'system', 'body' => 'Ich konnte gerade keine Antwort generieren. Bitte versuche es erneut oder stoppe die KI mit 🛑.', 'at' => now()->toIso8601String()];
        }

        $this->saveState($request, $state);
        return response()->json($state);
    }

    private function askOllama(array $state): ?string
    {
        $host = rtrim(env('OLLAMA_HOST', 'http://127.0.0.1:11434'), '/');
        $model = env('OLLAMA_MODEL', 'llama3');
        if (!$host) return null;

        $topic = $state['topic'] ? (string) $state['topic'] : 'Allgemeiner Support';
        $hasAccess = $state['data_access_granted'] ?? false;

        $system = "Du bist ein hilfsbereiter Casino-Support-Assistent. Antworte knapp, freundlich und in deutscher Sprache. Frage maximal eine Rückfrage gleichzeitig. Wenn du eine Frage nicht beantworten kannst oder der Nutzer frustriert wirkt, antworte NUR mit dem Wort `[HANDOFF]`. Thema: {$topic}.";

        if (!$hasAccess) {
            $system .= "\n\nWICHTIG: Du hast AKTUELL KEINEN ZUGRIFF auf Nutzerdaten. Wenn der Nutzer nach persönlichen Informationen fragt (z.B. E-Mail, Guthaben, Boni, Transaktionen), antworte SOFORT und AUSSCHLIESSLICH mit dem Wort `[REQUEST_DATA]`. Erkläre nichts, entschuldige dich nicht. Nur `[REQUEST_DATA]`.";
        } else {
            $contextJson = '';
            try {
                // REPLACED DB CALLS WITH API CALLS
                $u = Auth::user();
                if ($u) {
                    $apiBase = config('app.api_url');
                    // We assume the user is authenticated via a token or session that is passed along.
                    // Since we are in a local environment acting as a client, we might need to forward the token.
                    // For now, we assume the API endpoints are protected and we need a way to call them.
                    // If Auth::user() works, it means we have a session.

                    // Fetch data from external API
                    // Note: In a real microservice setup, we would pass the user's token.
                    // Here we try to fetch from the API using the configured base URL.

                    // Example: Fetch Wallets
                    $walletsResp = Http::acceptJson()->get($apiBase . '/user/wallets');
                    $wallets = $walletsResp->ok() ? $walletsResp->json() : [];

                    // Example: Fetch Bonuses
                    $bonusesResp = Http::acceptJson()->get($apiBase . '/user/bonuses/active');
                    $activeBonuses = $bonusesResp->ok() ? $bonusesResp->json() : [];

                    $ctx = [
                        'user' => [
                            'username' => $u->username ?? $u->name,
                            'email' => $u->email,
                            'id' => $u->id
                        ],
                        'wallets' => $wallets,
                        'active_bonuses' => $activeBonuses,
                    ];
                    $contextJson = json_encode($ctx, JSON_UNESCAPED_UNICODE | JSON_PRETTY_PRINT);
                }
            } catch (\Throwable $e) {
                // Fallback if API calls fail
                \Illuminate\Support\Facades\Log::error('Failed to fetch remote context: ' . $e->getMessage());
            }

            if ($contextJson) {
                $system .= "\n\nNutzerdaten (ZUGRIFF ERLAUBT):\n" . $contextJson . "\n\nDU DARFST DIESE DATEN JETZT VERWENDEN. Die Daten im JSON beziehen sich AUSSCHLIESSLICH auf den aktuellen Gesprächspartner. Wenn der Nutzer nach seinen EIGENEN Daten fragt (z.B. 'meine E-Mail', 'mein Guthaben'), antworte ihm direkt mit den Werten aus dem JSON. Wenn der Nutzer nach den Daten einer ANDEREN Person fragt (z.B. 'die E-Mail von Bingo'), musst du die Anfrage ablehnen und antworten, dass du nur Auskunft über sein eigenes Konto geben darfst.";
            }
        }

        $recent = array_slice($state['messages'], -10);
        $chatText = $system."\n\n";
        foreach ($recent as $m) {
            $role = $m['sender'] === 'user' ? 'User' : ucfirst($m['sender']);
            $chatText .= "{$role}: {$m['body']}\n";
        }
        $chatText .= "Assistant:";

        try {
            $res = Http::timeout(12)->post($host.'/api/generate', [
                'model' => $model,
                'prompt' => $chatText,
                'stream' => false,
                'options' => ['temperature' => 0.3, 'num_predict' => 180],
            ]);
            if (!$res->ok()) return null;
            $json = $res->json();
            $out = trim((string)($json['response'] ?? ''));
            return $out ?: null;
        } catch (\Throwable $e) {
            return null;
        }
    }

    public function status(Request $request) { return response()->json($this->sessionState($request)); }

    public function stop(Request $request)
    {
        abort_unless(Auth::check(), 401);
        $state = $this->sessionState($request);
        if (!$state['thread_id'] || ($state['status'] ?? null) === 'closed') {
            return response()->json(['error' => 'No active chat thread.'], 422);
        }
        if ($state['status'] === 'ai') {
            $state['status'] = 'stopped';
            $state['messages'][] = [
                'id' => Str::uuid()->toString(),
                'sender' => 'system',
                'body' => 'KI-Assistent gestoppt. Du kannst einen Mitarbeiter anfordern.',
                'at' => now()->toIso8601String(),
            ];
            $this->saveState($request, $state);
        }
        return response()->json($state);
    }

    public function handoff(Request $request) {
        $this->ensureEnabled();
        abort_unless(Auth::check(), 401);
        $state = $this->sessionState($request);
        if (!$state['thread_id']) return response()->json(['message' => 'No active support thread'], 422);
        $state['status'] = 'handoff';
        $state['messages'][] = ['id' => Str::uuid()->toString(), 'sender' => 'system', 'body' => 'Ich leite dich an einen Mitarbeiter weiter. Bitte habe einen Moment Geduld.', 'at' => now()->toIso8601String()];
        $this->saveState($request, $state);
        $webhook = env('SUPPORT_DASHBOARD_WEBHOOK_URL');
        if ($webhook) { try { Http::timeout(5)->post($webhook, ['event' => 'support.handoff', 'thread_id' => $state['thread_id']]); } catch (\Throwable $e) {} }
        return response()->json(['message' => 'Hand-off requested', 'state' => $state]);
    }
    public function stream(Request $request) {
        $state = $this->sessionState($request);
        if (empty($state['thread_id'])) return response('', 204);
        $threadId = $state['thread_id'];
        return new StreamedResponse(function () use ($request, $threadId) {
            $send = fn($data) => print('data: ' . json_encode($data) . "\n\n");
            $start = time();
            $lastUpdated = null;
            $lastCount = -1;
            while (time() - $start < 60) {
                usleep(500000);
                $cached = cache()->get('support_threads:'.$threadId);
                $nowState = is_array($cached) ? $cached : $this->sessionState($request);
                $count = count($nowState['messages'] ?? []);
                $updated = $nowState['updated_at'] ?? null;
                if ($count !== $lastCount || $updated !== $lastUpdated) {
                    $send($nowState);
                    $lastCount = $count;
                    $lastUpdated = $updated;
                }
                if ((time() - $start) % 15 === 0) { print(": ping\n\n"); }
                @ob_flush(); @flush();
            }
        }, 200, ['Content-Type' => 'text/event-stream', 'Cache-Control' => 'no-cache', 'Connection' => 'keep-alive', 'X-Accel-Buffering' => 'no']);
    }
}