<?php
/**
 * NY 问卷考试系统数据平台 - 后端接口
 */
declare(strict_types=1);

require __DIR__ . '/bootstrap.php';

$action = (string)($_GET['action'] ?? $_POST['action'] ?? '');

function cfg(): array
{
    return ny_load_config();
}

try {
    switch ($action) {
        // ---------------- 配置 ----------------
        case 'config_get':
            $c = cfg();
            $c['has_password'] = $c['password'] !== '';
            ny_ok($c);

        case 'config_save':
            $raw = (string)file_get_contents('php://input');
            $in  = json_decode($raw, true);
            if (!is_array($in)) {
                $in = $_POST;
            }
            $old = cfg();
            $allowed = ['base_url', 'api_prefix', 'username', 'password', 'timeout', 'refresh_interval', 'page_size', 'name_keywords'];
            $new = $old;
            foreach ($allowed as $k) {
                if (array_key_exists($k, $in)) {
                    $new[$k] = is_string($in[$k]) ? trim((string)$in[$k]) : $in[$k];
                }
            }
            foreach (['verify_ssl', 'include_temp_save', 'dedupe'] as $k) {
                if (array_key_exists($k, $in)) {
                    $new[$k] = filter_var($in[$k], FILTER_VALIDATE_BOOL);
                }
            }
            $pwdIn = $in['password'] ?? null;
            if ($pwdIn === null || $pwdIn === '' || $pwdIn === '******') {
                $new['password'] = $old['password'];
            }
            $new['base_url']   = rtrim($new['base_url'], '/');
            $new['api_prefix'] = '/' . trim((string)$new['api_prefix'], '/');
            $new['timeout']    = (int)$new['timeout'];
            $new['refresh_interval'] = (int)$new['refresh_interval'];
            if ($new['refresh_interval'] < 3) {
                $new['refresh_interval'] = 3;
            }
            // 每套试卷独立满分：选中试卷时写入 full_scores[projectId]，否则更新全局默认
            $fs = (int)($in['full_score'] ?? $new['full_score'] ?? 100);
            if ($fs < 1) {
                $fs = 100;
            }
            $pid = trim((string)($in['project_id'] ?? ''));
            if ($pid !== '') {
                $scores = is_array($new['full_scores'] ?? null) ? $new['full_scores'] : [];
                $scores[$pid] = $fs;
                $new['full_scores'] = $scores;
            } else {
                $new['full_score'] = $fs;
            }
            ny_save_config($new);
            @unlink(NY_DATA . '/cache/token.json'); // 清掉旧令牌
            ny_ok(['saved' => true, 'config' => ny_load_config()]);

        // ---------------- 连接测试 ----------------
        case 'ping':
            $client = new SurveyKingClient(cfg());
            $res = $client->ping();
            $res['session'] = $client->sessionInfo();
            ny_ok($res);

        case 'diag':
            $client = new SurveyKingClient(cfg());
            ny_ok($client->diagnose());

        // ---------------- 问卷列表 ----------------
        case 'projects':
            $client = new SurveyKingClient(cfg());
            $list   = $client->listProjects();
            $out    = [];
            foreach ($list as $p) {
                if (!is_array($p)) {
                    continue;
                }
                $out[] = [
                    'id'    => ny_str($p['id'] ?? ''),
                    'name'  => ny_str($p['name'] ?? '') ?: '未命名',
                    'mode'  => ny_str($p['mode'] ?? ''),
                    'total' => (int)($p['total'] ?? 0),
                    'status'=> (int)($p['status'] ?? 0),
                ];
            }
            ny_ok($out);

        // ---------------- 数据 ----------------
        case 'data':
            $projectId = (string)($_GET['projectId'] ?? '');
            if ($projectId === '') {
                ny_fail('请先选择问卷/考试');
            }
            $nameQid = (string)($_GET['nameQid'] ?? '');
            $c = cfg();
            $result = DataService::build($c, $projectId, $nameQid);
            $fsMap = is_array($c['full_scores'] ?? null) ? $c['full_scores'] : [];
            $fs = isset($fsMap[$projectId]) ? (int)$fsMap[$projectId] : (int)($c['full_score'] ?? 100);
            if ($fs < 1) {
                $fs = 100;
            }
            $result['config'] = [
                'refresh_interval'  => (int)$c['refresh_interval'],
                'base_url'          => $c['base_url'],
                'full_score'        => $fs,
            ];
            ny_ok($result);

        // ---------------- 数据看板（按班级聚合，面向班主任/学生整体情况） ----------------
        case 'dashboard':
            $projectId = (string)($_GET['projectId'] ?? '');
            if ($projectId === '') {
                ny_fail('请先选择问卷/考试');
            }
            $nameQid = (string)($_GET['nameQid'] ?? '');
            $c = cfg();
            $result = DataService::build($c, $projectId, $nameQid);
            $fsMap = is_array($c['full_scores'] ?? null) ? $c['full_scores'] : [];
            $fs = isset($fsMap[$projectId]) ? (int)$fsMap[$projectId] : (int)($c['full_score'] ?? 100);
            if ($fs < 1) {
                $fs = 100;
            }

            $students = $result['roster'] ?: [];
            $rows     = $result['rows'] ?: [];

            $byCls = [];
            foreach ($students as $s) {
                $k = trim((string)($s['cls'] ?? '')) ?: '（未分班）';
                $byCls[$k][] = $s;
            }
            $rowsByCls = [];
            foreach ($rows as $r) {
                $k = trim((string)($r['cls'] ?? '')) ?: '（未分班）';
                $rowsByCls[$k][] = $r;
            }

            $classes = [];
            foreach ($byCls as $k => $stu) {
                $rs       = $rowsByCls[$k] ?? [];
                $total    = count($stu);
                $submitted = count($rs);
                $scores   = array_values(array_filter(array_map(static fn($r) => $r['score'] ?? null, $rs), static fn($v) => $v !== null));
                $avg      = $scores !== [] ? round(array_sum($scores) / count($scores), 2) : null;
                $pass     = count(array_filter($rs, static fn($r) => ($r['score'] ?? null) !== null && ($r['score'] >= 0.6 * $fs)));
                $passRate = $submitted > 0 ? round($pass / $submitted * 100, 1) : 0;
                $durs     = array_values(array_filter(array_map(static fn($r) => $r['duration'] ?? null, $rs), static fn($v) => $v !== null));
                $avgDur   = $durs !== [] ? (int)round(array_sum($durs) / count($durs)) : null;
                $classes[] = [
                    'class'         => $k,
                    'total'         => $total,
                    'submitted'     => $submitted,
                    'absent'        => max(0, $total - $submitted),
                    'rate'          => $total > 0 ? round($submitted / $total * 100, 1) : 0,
                    'avg'           => $avg,
                    'pass_rate'     => $passRate,
                    'max'           => $scores !== [] ? max($scores) : null,
                    'min'           => $scores !== [] ? min($scores) : null,
                    'avg_duration'  => $avgDur,
                ];
            }
            usort($classes, static function (array $a, array $b): int {
                $an = is_numeric($a['class']) ? (int)$a['class'] : $a['class'];
                $bn = is_numeric($b['class']) ? (int)$b['class'] : $b['class'];
                if (is_int($an) && is_int($bn)) {
                    return $an <=> $bn;
                }
                return strcmp((string)$a['class'], (string)$b['class']);
            });

            ny_ok([
                'project'    => $result['project'],
                'full_score' => $fs,
                'overall'    => $result['stats'],
                'classes'    => $classes,
                'updated_at' => $result['updated_at'],
            ]);

        // ---------------- 名单 ----------------
        case 'roster':
            ny_ok(['students' => Roster::all(), 'meta' => Roster::meta()]);

        case 'roster_import':
            if (empty($_FILES['file']) || !is_uploaded_file($_FILES['file']['tmp_name'])) {
                ny_fail('请选择要导入的文件');
            }
            $f    = $_FILES['file'];
            $ext  = strtolower(pathinfo((string)$f['name'], PATHINFO_EXTENSION));
            $dest = NY_DATA . '/uploads/roster_' . date('Ymd_His') . '.' . ($ext !== '' ? $ext : 'dat');
            if (!@move_uploaded_file($f['tmp_name'], $dest)) {
                ny_fail('文件保存失败，请检查 data/uploads 目录权限');
            }
            try {
                $res = Roster::importFile($dest, $ext);
            } catch (Throwable $e) {
                @unlink($dest);
                ny_fail($e->getMessage());
            }
            $mode = (string)($_POST['mode'] ?? 'replace');
            if ($mode === 'append') {
                $merged = array_merge(Roster::all(), $res['students']);
                Roster::save($merged);
            } else {
                Roster::save($res['students']);
            }
            ny_ok(['students' => Roster::all(), 'meta' => Roster::meta(), 'imported' => $res['count']]);

        case 'roster_save':
            $raw = (string)file_get_contents('php://input');
            $in  = json_decode($raw, true);
            if (!is_array($in) || !isset($in['students']) || !is_array($in['students'])) {
                ny_fail('参数错误');
            }
            $students = [];
            foreach ($in['students'] as $s) {
                if (!is_array($s)) {
                    continue;
                }
                $students[] = [
                    'sid'  => (string)($s['sid'] ?? ''),
                    'name' => (string)($s['name'] ?? ''),
                    'cls'  => trim((string)($s['cls'] ?? '')),
                ];
            }
            Roster::save($students);
            ny_ok(['students' => Roster::all(), 'meta' => Roster::meta()]);

        case 'roster_clear':
            Roster::clear();
            ny_ok(['students' => [], 'meta' => Roster::meta()]);

        // ---------------- 导出 ----------------
        case 'export':
        case 'export_absent':
            $projectId = (string)($_GET['projectId'] ?? '');
            if ($projectId === '') {
                ny_fail('请先选择问卷/考试');
            }
            $nameQid = (string)($_GET['nameQid'] ?? '');
            $c = cfg();
            $result = DataService::build($c, $projectId, $nameQid);
            $filename = ($action === 'export_absent' ? '缺考名单' : '成绩明细')
                . '_' . preg_replace('/[\\\\\/:*?"<>|]/u', '_', (string)$result['project']['name'])
                . '_' . date('Ymd_His') . '.csv';

            header('Content-Type: text/csv; charset=utf-8');
            header('Content-Disposition: attachment; filename="' . $filename . '"');
            header('Cache-Control: no-store');
            echo "\xEF\xBB\xBF";
            $out = fopen('php://output', 'w');

            if ($action === 'export_absent') {
                fputcsv($out, ['学号', '姓名', '班级']);
                foreach ($result['absent'] as $r) {
                    fputcsv($out, [$r['sid'], $r['name'], $r['cls'] ?? '']);
                }
            } else {
                fputcsv($out, ['学号', '姓名', '班级', '成绩', '提交时间', '考试时长', '考试时长(秒)']);
                foreach ($result['rows'] as $r) {
                    fputcsv($out, [
                        $r['sid'],
                        $r['name'],
                        $r['cls'] ?? '',
                        $r['score'] === null ? '' : $r['score'],
                        $r['submit_at'],
                        $r['duration_txt'],
                        $r['duration'] === null ? '' : $r['duration'],
                    ]);
                }
            }
            fclose($out);
            exit;

        default:
            ny_fail('未知操作：' . $action);
    }
} catch (Throwable $e) {
    ny_fail($e->getMessage(), [
        'trace' => defined('NY_DEBUG') && NY_DEBUG ? $e->getTraceAsString() : null,
    ]);
}