<?php
/**
 * AJAX API voor Dagplanning & Taken
 */

require_once __DIR__ . '/../includes/auth.php';
$user = require_auth();
$db = get_db_connection();

header('Content-Type: application/json');

$action = $_GET['action'] ?? ($_POST['action'] ?? '');
$today = date('Y-m-d');

try {
    // 1. Dagdoel of notities opslaan
    if ($action === 'save_goal') {
        $data = json_decode(file_get_contents('php://input'), true);
        $date = $data['date'] ?? $today;
        $focusGoal = $data['focus_goal'] ?? '';
        $notes = $data['notes'] ?? '';

        $stmt = $db->prepare("
            INSERT INTO daily_plans (user_id, plan_date, focus_goal, notes)
            VALUES (?, ?, ?, ?)
            ON DUPLICATE KEY UPDATE focus_goal = VALUES(focus_goal), notes = VALUES(notes)
        ");
        $stmt->execute([$user['id'], $date, $focusGoal, $notes]);

        echo json_encode(['success' => true]);
        exit;
    }

    // 2. Taak toevoegen
    if ($action === 'add_task') {
        $data = json_decode(file_get_contents('php://input'), true);
        $title = trim($data['title'] ?? '');
        $priority = in_array($data['priority'] ?? '', ['P1', 'P2', 'P3']) ? $data['priority'] : 'P2';
        $timeBlockStart = $data['time_block_start'] ?? null;
        $date = $data['date'] ?? $today;

        if (empty($title)) {
            echo json_encode(['error' => 'Titel is verplicht']);
            exit;
        }

        // Haal of maak daily plan op
        $stmtPlan = $db->prepare("
            INSERT INTO daily_plans (user_id, plan_date)
            VALUES (?, ?)
            ON DUPLICATE KEY UPDATE id=LAST_INSERT_ID(id)
        ");
        $stmtPlan->execute([$user['id'], $date]);
        $planId = $db->lastInsertId();

        $source = !empty($data['source']) ? substr(trim($data['source']), 0, 50) : 'FOCIZ';
        $externalId = !empty($data['external_id']) ? substr(trim($data['external_id']), 0, 100) : null;
        $externalUrl = !empty($data['external_url']) ? trim($data['external_url']) : null;

        $stmt = $db->prepare("
            INSERT INTO tasks (user_id, daily_plan_id, title, priority, time_block_start, status, source, external_id, external_url)
            VALUES (?, ?, ?, ?, ?, 'TODO', ?, ?, ?)
        ");
        $stmt->execute([$user['id'], $planId, $title, $priority, $timeBlockStart, $source, $externalId, $externalUrl]);
        $taskId = (int)$db->lastInsertId();

        echo json_encode([
            'success' => true,
            'task' => [
                'id' => $taskId,
                'title' => $title,
                'priority' => $priority,
                'time_block_start' => $timeBlockStart,
                'is_completed' => 0,
                'status' => 'TODO'
            ]
        ]);
        exit;
    }

    // 3. Taak status toggelen (voltooid / open)
    if ($action === 'toggle_task') {
        $data = json_decode(file_get_contents('php://input'), true);
        $taskId = (int)($data['task_id'] ?? 0);
        $isCompleted = !empty($data['is_completed']) ? 1 : 0;
        $status = $isCompleted ? 'DONE' : 'TODO';

        $stmt = $db->prepare("
            UPDATE tasks SET is_completed = ?, status = ?
            WHERE id = ? AND user_id = ?
        ");
        $stmt->execute([$isCompleted, $status, $taskId, $user['id']]);

        echo json_encode(['success' => true]);
        exit;
    }

    // 4. Taak verwijderen
    if ($action === 'delete_task') {
        $data = json_decode(file_get_contents('php://input'), true);
        $taskId = (int)($data['task_id'] ?? 0);

        $stmt = $db->prepare("DELETE FROM tasks WHERE id = ? AND user_id = ?");
        $stmt->execute([$taskId, $user['id']]);

        echo json_encode(['success' => true]);
        exit;
    }

    echo json_encode(['error' => 'Onbekende actie']);
} catch (Exception $e) {
    http_response_code(500);
    echo json_encode(['error' => $e->getMessage()]);
}