<?php
declare(strict_types=1);

header('Content-Type: application/json; charset=utf-8');

if (session_status() === PHP_SESSION_NONE) {
	session_start();
}

require_once __DIR__ . '/../db_conn.php';
require_once __DIR__ . '/common.php';

$sessionUser = api_get_session_user();
$memberId    = (string)($sessionUser['member_id'] ?? $_SESSION['member_id'] ?? '');
$sysCompCode = (string)($sessionUser['sys_comp_code'] ?? $_SESSION['sys_comp_code'] ?? '');

if ($memberId === '') {
	http_response_code(401);
	echo json_encode(['success' => false, 'message' => 'not_logged_in'], JSON_UNESCAPED_UNICODE);
	exit;
}

try {
	$pdo = db_conn();

	$fixedLegalNameMap = [
		'C01' => '개인정보보호',
		'C02' => '직장내 괴롭힘 예방',
		'C03' => '장애인 인식 개선',
		'C04' => '성희롱 예방 교육',
		'C05' => '퇴직금 교육',
	];

	$normalizeLegalGroupCode = static function ($value) {
		$code = strtoupper(trim((string)$value));
		if (preg_match('/^CA200(C\d{2})$/', $code, $m)) {
			return $m[1];
		}
		if (preg_match('/^C\d{2}$/', $code)) {
			return $code;
		}
		return '';
	};

	$legalCodes = array_keys($fixedLegalNameMap);
	$legalRawCodes = [];
	foreach ($legalCodes as $code) {
		$legalRawCodes[] = $code;
		$legalRawCodes[] = 'CA200' . $code;
	}
	$legalRawCodes = array_values(array_unique($legalRawCodes));
	$phCodes = implode(',', array_fill(0, count($legalRawCodes), '?'));

	// 법정교육(CA10003) 컨텐츠를 category_group 기준으로 조회
	$sql = "
		SELECT
			c.content_id,
			c.title,
			c.content_url,
			c.thumbnail_url,
			c.category_code,
			c.category_group,
			c.description,
			c.sort_order,
			lh.watch_tm,
			lh.content_tm,
			lh.all_tm,
			lh.completed_at
		FROM edu_contents c
		LEFT JOIN edu_learning_histories lh
			ON lh.content_id = c.content_id
			AND lh.member_id = ?
			AND lh.sys_comp_code = ?
		WHERE c.category_code = 'CA10003'
		  AND c.is_active = 1
		  AND c.category_group IN ($phCodes)
		ORDER BY c.category_group ASC, c.sort_order ASC, c.content_id ASC
	";

	$stmt = $pdo->prepare($sql);
	$stmt->execute(array_merge([$memberId, $sysCompCode], $legalRawCodes));
	$rows = $stmt->fetchAll(PDO::FETCH_ASSOC) ?: [];

	$chapterMap = [];
	foreach ($legalCodes as $index => $code) {
		$chapterMap[$code] = [
			'code' => $code,
			'name' => $fixedLegalNameMap[$code] ?? $code,
			'lessons' => [],
		];
	}

	foreach ($rows as $row) {
		$groupCode = $normalizeLegalGroupCode($row['category_group'] ?? '');
		if ($groupCode === '' || !isset($chapterMap[$groupCode])) {
			continue;
		}

		// YouTube videoId 추출
		$raw = trim($row['content_url'] ?? '');
		$videoId = '';
		if (preg_match('/(?:v=|youtu\.be\/)([A-Za-z0-9_-]{11})/', $raw, $m)) {
			$videoId = $m[1];
		} elseif (preg_match('/^[A-Za-z0-9_-]{11}$/', $raw)) {
			$videoId = $raw;
		}

		$title = $row['title'] ?? '';
		$watchTm   = (int)($row['watch_tm'] ?? 0);
		$contentTm = (int)($row['content_tm'] ?? 0);
		$completed = !empty($row['completed_at']);

		$chapterMap[$groupCode]['lessons'][] = [
			'content_id' => $row['content_id'] ?? '',
			'title'      => $title,
			'url'        => $videoId,
			'description'=> (string)($row['description'] ?? ''),
			'sort_order' => (int)($row['sort_order'] ?? 0),
			'watch_tm'   => $watchTm,
			'content_tm' => $contentTm,
			'all_tm'     => (int)($row['all_tm'] ?? 0),
			'completed'  => $completed,
		];
	}

	$chapters = [];
	foreach ($legalCodes as $code) {
		$chapter = $chapterMap[$code];
		usort($chapter['lessons'], static function ($left, $right) {
			$sortDiff = (int)($left['sort_order'] ?? 0) <=> (int)($right['sort_order'] ?? 0);
			if ($sortDiff !== 0) {
				return $sortDiff;
			}

			return strcmp((string)($left['content_id'] ?? ''), (string)($right['content_id'] ?? ''));
		});

		$chapters[] = [
			'code' => $chapter['code'],
			'name' => $chapter['name'],
			'lessons' => array_map(static function ($lesson) {
				unset($lesson['sort_order']);
				return $lesson;
			}, $chapter['lessons']),
		];
	}

	echo json_encode([
		'success'  => true,
		'chapters' => $chapters,
	], JSON_UNESCAPED_UNICODE);

} catch (Throwable $e) {
	http_response_code(500);
	echo json_encode([
		'success' => false,
		'message' => 'server_error',
	], JSON_UNESCAPED_UNICODE);
}