<?php
require_once 'db/config.php';
require_once 'layout_header.php';

$pdo = db();

// Create scheduled_posts table if it doesn't exist
$pdo->exec("CREATE TABLE IF NOT EXISTS scheduled_posts (
    id INT AUTO_INCREMENT PRIMARY KEY,
    channel_id INT NOT NULL,
    message TEXT NOT NULL,
    scheduled_at DATETIME NOT NULL,
    status VARCHAR(20) NOT NULL DEFAULT 'pending',
    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
    FOREIGN KEY (channel_id) REFERENCES channels(id) ON DELETE CASCADE
);");

$message = '';
$type = '';

// Handle deletion of a scheduled post
if ($_SERVER['REQUEST_METHOD'] === 'POST' && isset($_POST['action']) && $_POST['action'] === 'delete_post') {
    $post_id_to_delete = $_POST['post_id'] ?? 0;
    if ($post_id_to_delete > 0) {
        try {
            $delete_stmt = $pdo->prepare("DELETE FROM scheduled_posts WHERE id = ?");
            $delete_stmt->execute([$post_id_to_delete]);
            $message = 'Scheduled post cancelled successfully.';
            $type = 'success';
        } catch (PDOException $e) {
            $message = 'Error cancelling post: ' . $e->getMessage();
            $type = 'danger';
        }
    }
}

// Handle form submission for bulk scheduling
if ($_SERVER['REQUEST_METHOD'] === 'POST' && isset($_POST['schedule_post'])) {
    $channel_id = $_POST['channel_id'];
    $post_idea = $_POST['message'];
    $schedule_date = $_POST['schedule_date'];
    $post_count = isset($_POST['post_count']) ? (int)$_POST['post_count'] : 0;

    if (empty($channel_id) || empty($post_idea) || empty($schedule_date) || $post_count <= 0) {
        $message = 'Please fill out all fields and specify a valid number of posts.';
        $type = 'danger';
    } else {
        try {
            $pdo->beginTransaction();

            $stmt = $pdo->prepare("INSERT INTO scheduled_posts (channel_id, message, scheduled_at) VALUES (?, ?, ?)");
            
            // Fetch webhook URL and channel identifier once before the loop
            $webhook_stmt = $pdo->query("SELECT setting_value FROM settings WHERE setting_key = 'webhook_new_post'");
            $webhook_url = $webhook_stmt->fetchColumn();
            $identifier_stmt = $pdo->prepare("SELECT channel_identifier FROM channels WHERE id = ?");
            $identifier_stmt->execute([$channel_id]);
            $channel_identifier = $identifier_stmt->fetchColumn();

            $start_hour = 8; // 8 AM
            $end_hour = 22; // 10 PM
            $total_hours = $end_hour - $start_hour;
            $interval_minutes = ($post_count > 1) ? floor(($total_hours * 60) / ($post_count - 1)) : 0;

            $posts_scheduled = 0;
            for ($i = 0; $i < $post_count; $i++) {
                $minutes_to_add = $i * $interval_minutes;
                $scheduled_datetime = new DateTime($schedule_date . ' ' . $start_hour . ':00');
                $scheduled_datetime->add(new DateInterval('PT' . $minutes_to_add . 'M'));
                $scheduled_at_str = $scheduled_datetime->format('Y-m-d H:i:s');

                $stmt->execute([$channel_id, $post_idea, $scheduled_at_str]);
                $last_post_id = $pdo->lastInsertId();

                // Trigger webhook for each post
                if ($webhook_url && $channel_identifier) {
                    $post_data = [
                        'event' => 'new_post_scheduled',
                        'post_id' => $last_post_id,
                        'channel_identifier' => $channel_identifier,
                        'post_text_idea' => $post_idea,
                        'scheduled_at_utc' => gmdate('Y-m-d H:i:s', strtotime($scheduled_at_str))
                    ];

                    $ch = curl_init($webhook_url);
                    curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
                    curl_setopt($ch, CURLOPT_POST, true);
                    curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode($post_data));
                    curl_setopt($ch, CURLOPT_HTTPHEADER, ['Content-Type: application/json']);
                    curl_exec($ch);
                    curl_close($ch);
                }
                $posts_scheduled++;
            }

            $pdo->commit();
            $message = "$posts_scheduled post(s) scheduled successfully!";
            $type = 'success';

        } catch (Exception $e) {
            $pdo->rollBack();
            $message = 'Error scheduling posts: ' . $e->getMessage();
            $type = 'danger';
        }
    }
}

// Fetch channels for the dropdown
try {
    $channels_stmt = $pdo->query("SELECT id, channel_identifier FROM channels ORDER BY channel_identifier ASC");
    $channels = $channels_stmt->fetchAll(PDO::FETCH_ASSOC);
} catch (PDOException $e) {
    $channels = [];
    $message = 'Error fetching channels: ' . $e->getMessage();
    $type = 'danger';
}

// Fetch scheduled posts for the table
try {
    $posts_stmt = $pdo->query("
        SELECT sp.id, c.channel_identifier, sp.message, sp.scheduled_at, sp.status
        FROM scheduled_posts sp
        JOIN channels c ON sp.channel_id = c.id
        ORDER BY sp.scheduled_at ASC
    ");
    $scheduled_posts = $posts_stmt->fetchAll(PDO::FETCH_ASSOC);
} catch (PDOException $e) {
    $scheduled_posts = [];
    $message = 'Error fetching scheduled posts: ' . $e->getMessage();
    $type = 'danger';
}

?>

<div class="container-fluid p-4">
    <h1 class="h3 mb-4 text-white">Scheduler</h1>

    <?php if ($message): ?>
        <div class="alert alert-<?php echo $type; ?> alert-dismissible fade show" role="alert">
            <?php echo htmlspecialchars($message); ?>
            <button type="button" class="btn-close" data-bs-dismiss="alert" aria-label="Close"></button>
        </div>
    <?php endif; ?>

    <!-- Schedule Posts Form -->
    <div class="card bg-dark-surface mb-4">
        <div class="card-header">
            <h5 class="card-title mb-0">Bulk Schedule Posts</h5>
        </div>
        <div class="card-body">
            <form method="POST" action="scheduler.php">
                <div class="row">
                    <div class="col-md-6 mb-3">
                        <label for="channel_id" class="form-label">Channel</label>
                        <select class="form-select" id="channel_id" name="channel_id" required>
                            <option value="" disabled selected>Select a channel</option>
                            <?php foreach ($channels as $channel): ?>
                                <option value="<?php echo $channel['id']; ?>">
                                    <?php echo htmlspecialchars($channel['channel_identifier']); ?>
                                </option>
                            <?php endforeach; ?>
                        </select>
                    </div>
                    <div class="col-md-3 mb-3">
                        <label for="schedule_date" class="form-label">Date</label>
                        <input type="date" class="form-control" id="schedule_date" name="schedule_date" required>
                    </div>
                    <div class="col-md-3 mb-3">
                        <label for="post_count" class="form-label">Number of Posts</label>
                        <input type="number" class="form-control" id="post_count" name="post_count" min="1" max="100" value="1" required>
                    </div>
                </div>
                <div class="mb-3">
                    <label for="message" class="form-label">Post Idea / Prompt</label>
                    <textarea class="form-control" id="message" name="message" rows="3" required placeholder="e.g., A motivational quote about success"></textarea>
                    <div class="form-text">This text will be sent to your n8n workflow as a prompt for AI content generation.</div>
                </div>
                <button type="submit" name="schedule_post" class="btn btn-primary">Schedule Posts</button>
            </form>
        </div>
    </div>

    <!-- Scheduled Posts Table -->
    <div class="card bg-dark-surface">
        <div class="card-header">
            <h5 class="card-title mb-0">Upcoming Posts</h5>
        </div>
        <div class="card-body">
            <div class="table-responsive">
                <table class="table table-dark table-hover">
                    <thead>
                        <tr>
                            <th>ID</th>
                            <th>Channel</th>
                            <th>Message</th>
                            <th>Scheduled Time</th>
                            <th>Status</th>
                            <th>Actions</th>
                        </tr>
                    </thead>
                    <tbody>
                        <?php if (empty($scheduled_posts)): ?>
                            <tr>
                                <td colspan="6" class="text-center text-muted">No posts scheduled yet.</td>
                            </tr>
                        <?php else: ?>
                            <?php 
                            $current_date = null;
                            foreach ($scheduled_posts as $post): 
                                $post_date = date("F j, Y", strtotime($post['scheduled_at']));
                                if ($post_date !== $current_date):
                                    $current_date = $post_date;
                            ?>
                                <tr class="table-group-divider">
                                    <td colspan="6" class="bg-secondary text-white"><strong><?php echo $current_date; ?></strong></td>
                                </tr>
                            <?php endif; ?>
                                <tr>
                                    <td><?php echo $post['id']; ?></td>
                                    <td><?php echo htmlspecialchars($post['channel_identifier']); ?></td>
                                    <td><?php echo nl2br(htmlspecialchars(substr($post['message'], 0, 80))) . (strlen($post['message']) > 80 ? '...' : ''); ?></td>
                                    <td><?php echo date("g:i a", strtotime($post['scheduled_at'])); ?></td>
                                    <td><span class="badge bg-warning text-dark"><?php echo htmlspecialchars(ucfirst($post['status'])); ?></span></td>
                                    <td>
                                        <form method="POST" action="scheduler.php" onsubmit="return confirm('Are you sure you want to cancel this post?');" style="display: inline;">
                                            <input type="hidden" name="action" value="delete_post">
                                            <input type="hidden" name="post_id" value="<?php echo $post['id']; ?>">
                                            <button type="submit" class="btn btn-danger btn-sm">Cancel</button>
                                        </form>
                                    </td>
                                </tr>
                            <?php endforeach; ?>
                        <?php endif; ?>
                    </tbody>
                </table>
            </div>
        </div>
    </div>
</div>

<?php
require_once 'layout_footer.php';
?>