<?php
header('Content-Type: application/json; charset=utf-8');
require_once __DIR__ . '/../../bbs/db_conn.php';
require_once __DIR__ . '/../../bbs/auth.php';
edu_require_login();

$pdo = db_conn();

$year = $_GET['year'] ?? date('Y');
$quarter_raw = $_GET['quarter'] ?? ceil(date('n') / 3);

// Convert quarter code (e.g., CA200Q01, CA200001) to integer 1~4
if (is_string($quarter_raw) && strpos($quarter_raw, 'CA200') === 0) {
    $quarter = (int) substr($quarter_raw, -1);
} else {
    $quarter = (int) $quarter_raw;
}
if ($quarter < 1 || $quarter > 4)
    $quarter = 1;

// Calculate start and end dates for the quarter
$p_fr_dt = $year . '-' . sprintf('%02d', ($quarter - 1) * 3 + 1) . '-01';
$p_to_dt = date('Y-m-t', strtotime($year . '-' . sprintf('%02d', $quarter * 3) . '-01'));
$p_fr_dt_full = $p_fr_dt . ' 00:00:00';
$p_to_dt_full = $p_to_dt . ' 23:59:59';

$response = [
    'success' => true,
    'data' => []
];

try {
    // 1. 전체학습자(quarter_qty)
    $stmt_q1 = $pdo->prepare("
        SELECT COUNT(*) as quarter_qty FROM edu_users 
        WHERE join_date <= ?
        AND (end_date >= ? OR end_date IS NULL)
    ");
    $stmt_q1->execute([$p_to_dt_full, $p_fr_dt_full]);
    $quarter_qty = (int) $stmt_q1->fetchColumn();

    // 2. 목표선택자(goals_qty)
    $stmt_q2 = $pdo->prepare("
        SELECT COUNT(b.member_id) as goals_qty
        FROM edu_learning_goals a
        JOIN edu_user_learning_goals b ON a.goal_code = b.goal_code
        WHERE 1=1
        AND b.is_active = '1' 
        AND a.base_year = ? AND RIGHT(a.quarter, 1) = ?
    ");
    $stmt_q2->execute([$year, $quarter]);
    $goals_qty = (int) $stmt_q2->fetchColumn();

    // 3. 목표달성자(goals_completed_qty)
    $stmt_q3 = $pdo->prepare("
        SELECT COUNT( b.member_id) as goals_completed_qty
        FROM edu_learning_goals a
        JOIN edu_user_learning_goals b ON a.goal_code = b.goal_code
        WHERE a.base_year = ? AND RIGHT(a.quarter, 1) = ? AND b.completed_date IS NOT NULL
    ");
    $stmt_q3->execute([$year, $quarter]);
    $goals_completed_qty = (int) $stmt_q3->fetchColumn();

    // 4. 목표별선택률
    $stmt_q4 = $pdo->prepare("
        SELECT a.sort_order 
             , a.title 
             , IFNULL(b.goal_qty, 0) as goal_qty
        FROM edu_learning_goals a
        LEFT JOIN ( SELECT goal_code , COUNT(0) AS goal_qty
                     FROM edu_user_learning_goals a
                     WHERE 1=1
                     AND is_active = '1'
                     AND RIGHT(a.quarter, 1) = ?
                     GROUP BY goal_code) b ON a.goal_code = b.goal_code
        WHERE 1=1
        AND a.is_active = '1' 
        AND RIGHT(a.quarter, 1) = ?
        ORDER BY a.sort_order
    ");
    $stmt_q4->execute([$quarter, $quarter]);
    $goal_selection_rate = $stmt_q4->fetchAll(PDO::FETCH_ASSOC);

    // 5. 법인별 비교
    $stmt_q5 = $pdo->prepare("
        SELECT fn_get_code_name(CONCAT('CO100', a.code)) AS comp_name
             , IFNULL(b.comp_qty,0) AS comp_qty
             , COUNT(DISTINCT u.member_id) as all_qty
        FROM edu_codes a
        LEFT JOIN edu_users u ON a.code = u.sys_comp_code AND (u.end_date >= ? OR u.end_date IS NULL)
        LEFT JOIN (
             SELECT sys_comp_code 
             , COUNT(0) AS comp_qty 
             FROM edu_user_learning_goals x
             WHERE 1=1
             AND is_active = '1' 
             AND RIGHT(x.quarter, 1) = ?
             GROUP BY sys_comp_code  ) b ON a.code = b.sys_comp_code
        WHERE 1=1
        AND a.group_code = 'CO100'
        GROUP BY a.code, fn_get_code_name(CONCAT('CO100', a.code)), b.comp_qty
        ORDER BY a.code
    ");
    $stmt_q5->execute([$p_fr_dt_full, $quarter]);
    $comp_selection_rate = $stmt_q5->fetchAll(PDO::FETCH_ASSOC);

    // Calculate derived metrics based on User's explicit formulas
    $target_rate = $quarter_qty > 0 ? round(($goals_qty / $quarter_qty) * 100) : 0;
    $achieve_rate = $goals_qty > 0 ? round(($goals_completed_qty / $goals_qty) * 100) : 0;
    $unselected_qty = $quarter_qty - $goals_qty;
    $unselected_rate = $quarter_qty > 0 ? round(($unselected_qty / $quarter_qty) * 100, 1) : 0;

    $response['data'] = [
        'kpi' => [
            'quarter_qty' => $quarter_qty,
            'goals_qty' => $goals_qty,
            'goals_completed_qty' => $goals_completed_qty,
            'target_rate' => $target_rate,
            'achieve_rate' => $achieve_rate,
            'unselected_qty' => $unselected_qty,
            'unselected_rate' => $unselected_rate
        ],
        'goals' => $goal_selection_rate,
        'comps' => $comp_selection_rate
    ];

} catch (PDOException $e) {
    $response['success'] = false;
    $response['error'] = 'DB Query Error: ' . $e->getMessage();
} catch (Exception $e) {
    $response['success'] = false;
    $response['error'] = 'Error: ' . $e->getMessage();
}

echo json_encode($response, JSON_UNESCAPED_UNICODE);