<?php

namespace App\Services\Notification;

use App\Services\Database\Connection;
use PDO;
use Throwable;

class TelegramNotifier
{
    private PDO $pdo;
    private ?string $botToken = null;
    private ?string $chatId = null;
    private ?string $lastError = null;

    public function __construct(Connection $connection)
    {
        $this->pdo = $connection->getPdo();
        $this->loadSettings();
    }

    /**
     * Load settings from database settings table.
     */
    public function loadSettings(): void
    {
        $this->botToken = $this->getSetting('telegram_bot_token');
        $this->chatId = $this->getSetting('telegram_chat_id');
    }

    /**
     * Helper to retrieve setting by key.
     */
    private function getSetting(string $key): ?string
    {
        try {
            $stmt = $this->pdo->prepare("SELECT `value` FROM settings WHERE `key` = ?");
            $stmt->execute([$key]);
            $val = $stmt->fetchColumn();
            return $val !== false ? $val : null;
        } catch (Throwable $e) {
            return null;
        }
    }

    /**
     * Configure manually (for testing unsaved parameters).
     */
    public function configure(string $botToken, string $chatId): void
    {
        $this->botToken = $botToken;
        $this->chatId = $chatId;
    }

    /**
     * Retrieve the last HTTP or API error message.
     */
    public function getLastError(): ?string
    {
        return $this->lastError;
    }

    /**
     * Send a notification to Telegram.
     */
    public function send(string $message, string $type = 'info'): bool
    {
        $this->lastError = null;

        if (!$this->botToken || !$this->chatId) {
            $this->lastError = "Telegram token or chat ID is missing.";
            return false;
        }

        $icons = [
            'info' => "\xF0\x9F\x93\xA1",      // 📡
            'success' => "\xE2\x9C\x85",         // ✅
            'warning' => "\xE2\x9A\xA0\xEF\xB8\x8F", // ⚠️
            'error' => "\xE2\x9D\x8C",           // ❌
            'opportunity' => "\xF0\x9F\x92\xA1", // 💡
            'funding' => "\xF0\x9F\x92\xB0",     // 💰
        ];

        $icon = $icons[$type] ?? $icons['info'];
        $fullMessage = "{$icon} *ScoutIQ*\n\n{$message}";

        try {
            $url = "https://api.telegram.org/bot{$this->botToken}/sendMessage";
            $payload = json_encode([
                'chat_id' => $this->chatId,
                'text' => $fullMessage,
                'parse_mode' => 'Markdown',
                'disable_web_page_preview' => true,
            ]);

            if (function_exists('curl_init')) {
                $ch = curl_init();
                curl_setopt($ch, CURLOPT_URL, $url);
                curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
                curl_setopt($ch, CURLOPT_POST, true);
                curl_setopt($ch, CURLOPT_POSTFIELDS, $payload);
                curl_setopt($ch, CURLOPT_HTTPHEADER, ['Content-Type: application/json']);
                curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
                curl_setopt($ch, CURLOPT_TIMEOUT, 10);

                $response = curl_exec($ch);
                if ($response === false) {
                    $this->lastError = "Connection error: " . curl_error($ch);
                    curl_close($ch);
                    return false;
                }

                $httpCode = curl_getinfo($ch, CURLINFO_HTTP_CODE);
                curl_close($ch);

                if ($httpCode !== 200) {
                    $resDecoded = json_decode($response, true);
                    $this->lastError = $resDecoded['description'] ?? "API error HTTP {$httpCode}";
                    error_log("Telegram API returned code {$httpCode}: {$response}");
                    return false;
                }

                return true;
            } else {
                $context = stream_context_create([
                    'http' => [
                        'method' => 'POST',
                        'header' => "Content-Type: application/json\r\n",
                        'content' => $payload,
                        'timeout' => 10,
                    ],
                    'ssl' => ['verify_peer' => false, 'verify_peer_name' => false],
                ]);

                $response = @file_get_contents($url, false, $context);
                if ($response === false) {
                    $error = error_get_last();
                    $this->lastError = $error['message'] ?? "Connection timed out.";
                    return false;
                }

                $resDecoded = json_decode($response, true);
                if (($resDecoded['ok'] ?? false) === false) {
                    $this->lastError = $resDecoded['description'] ?? "API error";
                    return false;
                }

                return true;
            }
        } catch (Throwable $e) {
            $this->lastError = $e->getMessage();
            return false;
        }
    }

    /**
     * Notify about a new opportunity.
     */
    public function notifyNewOpportunity(array $opportunity): void
    {
        $title = $opportunity['title'] ?? 'Untitled';
        $fitScore = $opportunity['fit_score'] ?? 0;
        $url = $opportunity['url'] ?? '';
        $orgName = $opportunity['org_name'] ?? '';
        $whyItMatters = $opportunity['why_it_matters'] ?? [];
        $requirements = $opportunity['requirements'] ?? [];
        $deadline = $opportunity['deadline'] ?? null;
        $effort = $opportunity['effort'] ?? 'متوسط';
        $potentialReturn = $opportunity['potential_return'] ?? 'متوسط';

        $effortEmoji = (str_contains($effort, 'عالي') || str_contains(strtolower($effort), 'high')) ? '🔴' : ((str_contains($effort, 'متوسط') || str_contains(strtolower($effort), 'medium')) ? '🟡' : '🟢');
        $returnEmoji = (str_contains($potentialReturn, 'عالي') || str_contains(strtolower($potentialReturn), 'high')) ? '🟢' : ((str_contains($potentialReturn, 'متوسط') || str_contains(strtolower($potentialReturn), 'medium')) ? '🟡' : '🔴');

        $message = "💡 *ScoutIQ*\n\n";
        $message .= "*{$title}*";
        if ($orgName) {
            $message .= " – {$orgName}";
        }
        
        $message .= "\n\n🔥 *Match Score:* {$fitScore}/100\n";
        
        if (!empty($whyItMatters)) {
            $message .= "\n*لماذا تهمك؟*\n";
            foreach ((array)$whyItMatters as $why) {
                $message .= "• {$why}\n";
            }
        }
        
        if (!empty($requirements)) {
            $message .= "\n*المتطلبات:*\n";
            foreach ((array)$requirements as $req) {
                $message .= "• {$req}\n";
            }
        }
        
        if ($deadline) {
            $message .= "\n*الموعد النهائي:*\n{$deadline}\n";
        }
        
        $message .= "\n*الجهد المطلوب:*\n{$effortEmoji} {$effort}\n";
        $message .= "\n*العائد المحتمل:*\n{$returnEmoji} {$potentialReturn}\n";
        
        $message .= "\n*الإجراء:*\n";
        if ($url) {
            $message .= "[قدم الآن]({$url})";
        } else {
            $message .= "لا يوجد رابط متاح";
        }

        $this->send($message, 'opportunity');
    }

    /**
     * Notify about collector results.
     */
    public function notifyCollectorResults(array $results): void
    {
        $message = "*Data Collection Complete*\n\n";
        $message .= "Sources: {$results['processed']}/{$results['total_sources']}\n";
        $message .= "New Opportunities: {$results['new_opportunities']}\n";
        $message .= "New Organizations: {$results['new_organizations']}\n";
        $message .= "Errors: {$results['errors']}";

        $this->send($message, 'success');
    }

    /**
     * Send test message.
     */
    public function sendTest(): bool
    {
        return $this->send("Test notification from ScoutIQ. Your Telegram integration is working correctly!", 'success');
    }
}