<?php
require_once __DIR__ . '/../config.php';

// Telegram Bot Configuration - Please change these
define('TELEGRAM_BOT_TOKEN', 'YOUR_TELEGRAM_BOT_TOKEN_HERE');
define('TELEGRAM_CHAT_ID', 'YOUR_TELEGRAM_CHAT_ID_HERE');

// Optionally get date from query param, default to today
$dateStr = isset($_GET['date']) ? $_GET['date'] : date('Y-m-d');
$date = new DateTime($dateStr);
$year = (int)$date->format('Y');
$month = (int)$date->format('n');
$day = (int)$date->format('j');

// Thai Date formatting
$thaiMonths = [
    1 => 'มกราคม', 2 => 'กุมภาพันธ์', 3 => 'มีนาคม', 4 => 'เมษายน',
    5 => 'พฤษภาคม', 6 => 'มิถุนายน', 7 => 'กรกฎาคม', 8 => 'สิงหาคม',
    9 => 'กันยายน', 10 => 'ตุลาคม', 11 => 'พฤศจิกายน', 12 => 'ธันวาคม'
];
$thaiDays = [
    'Sunday' => 'อาทิตย์', 'Monday' => 'จันทร์', 'Tuesday' => 'อังคาร',
    'Wednesday' => 'พุธ', 'Thursday' => 'พฤหัสบดี', 'Friday' => 'ศุกร์', 'Saturday' => 'เสาร์'
];

$thaiDateStr = "วัน" . $thaiDays[$date->format('l')] . "ที่ " . $day . " " . $thaiMonths[$month] . " " . ($year + 543);

try {
    // Get schedules for the target date
    $stmt = $pdo->prepare("
        SELECT s.shift_type, st.name, st.phone 
        FROM schedules s
        JOIN staff st ON s.staff_id = st.id
        WHERE s.year = :year AND s.month = :month AND s.day = :day
    ");
    $stmt->execute([':year' => $year, ':month' => $month, ':day' => $day]);
    $schedules = $stmt->fetchAll();

    if (empty($schedules)) {
        // No schedule for today, maybe send nothing or send a specific message
        $message = "\n📅 <b>ประกาศตารางเวร</b>\n$thaiDateStr\n\n✨ <i>วันนี้ไม่มีผู้เข้าเวรพักผ่อนให้เต็มที่ครับ</i> ✨";
    } else {
        $morning = [];
        $afternoon = [];
        $both = [];
        $leave = [];

        foreach ($schedules as $row) {
            $nameInfo = $row['name'];
            if (!empty($row['phone'])) {
                $nameInfo .= " (📞 " . $row['phone'] . ")";
            }

            if ($row['shift_type'] === 'ช') {
                $morning[] = $nameInfo;
            } elseif ($row['shift_type'] === 'บ') {
                $afternoon[] = $nameInfo;
            } elseif ($row['shift_type'] === 'ช/บ') {
                $both[] = $nameInfo;
            } elseif ($row['shift_type'] === 'ลา') {
                $leave[] = $nameInfo;
            }
        }

        // Build beautiful message using HTML tags for Telegram
        $message = "📢 <b>แจ้งเตือนตารางเวรประจำวัน</b> 📢\n";
        $message .= "🗓️ <b>$thaiDateStr</b>\n";
        $message .= str_repeat("➖", 12) . "\n\n";

        if (!empty($morning) || !empty($both)) {
            $message .= "🌅 <b>เวรเช้า (08:30 - 16:30 น.)</b>\n";
            foreach ($both as $name) {
                $message .= "  🔹 " . $name . "\n";
            }
            foreach ($morning as $name) {
                $message .= "  🔹 " . $name . "\n";
            }
            $message .= "\n";
        }

        if (!empty($afternoon) || !empty($both)) {
            $message .= "🌇 <b>เวรบ่าย (16:30 - 00:30 น.)</b>\n";
            foreach ($both as $name) {
                $message .= "  🔸 " . $name . "\n";
            }
            foreach ($afternoon as $name) {
                $message .= "  🔸 " . $name . "\n";
            }
            $message .= "\n";
        }

        if (!empty($leave)) {
            $message .= "⛔ <b>ลาพัก/ลากิจ</b>\n";
            foreach ($leave as $name) {
                $message .= "  ❌ " . $name . "\n";
            }
            $message .= "\n";
        }
        
        $message .= "💡 <i>ศูนย์คอมพิวเตอร์ ฝ่ายคอมพิวเตอร์และสารสนเทศ</i>";
    }

    // Only send to Telegram if token is set and not default
    if (TELEGRAM_BOT_TOKEN !== 'YOUR_TELEGRAM_BOT_TOKEN_HERE' && !empty(TELEGRAM_BOT_TOKEN)) {
        $url = "https://api.telegram.org/bot" . TELEGRAM_BOT_TOKEN . "/sendMessage";
        
        $postData = [
            'chat_id' => TELEGRAM_CHAT_ID,
            'text' => $message,
            'parse_mode' => 'HTML'
        ];
        
        $ch = curl_init();
        curl_setopt($ch, CURLOPT_URL, $url);
        curl_setopt($ch, CURLOPT_POST, 1);
        curl_setopt($ch, CURLOPT_POSTFIELDS, http_build_query($postData));
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
        curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
        $result = curl_exec($ch);
        curl_close($ch);
        
        echo json_encode([
            'status' => 'success',
            'message' => 'Notification sent successfully',
            'response' => json_decode($result),
            'text' => $message // For preview
        ]);
    } else {
        echo json_encode([
            'status' => 'success',
            'message' => 'Preview mode (No Telegram Token)',
            'text' => $message // For preview
        ]);
    }

} catch (PDOException $e) {
    http_response_code(500);
    echo json_encode(['status' => 'error', 'message' => $e->getMessage()]);
}
?>