refactor: 拆分 config.php 为 lib/ 模块，消除页面层重复代码

纯结构性重构，不改变任何功能。

- config.php 由 739 行缩减为 42 行，改为纯引导入口；新增 ROOT_DIR 常量
  统一拼接绝对路径（lib/ 内模块的 __DIR__ 会指向 lib/，必须替换）
- 新增 lib/ 五个模块 db.php / helpers.php / auth.php / movies.php / stats.php，
  由 config.php 按 db → helpers → auth → movies → stats 顺序加载
- add.php、edit.php 各自约 80 行重复的 POST 处理改为调用
  resolveCinemaId / resolvePersonIds / linkViewers / uploadImageFile /
  saveBase64Image / uploadMultiplePhotos / deleteStoredFile
- cinemas.php、persons.php 中重复 4 次的颜色校验改用 normalizeHexColor()
- toggleNewViewer / removeViewerRow / toggleNewCinema 下沉至 js/main.js，
  add.php 中的 removeViewer 统一更名为 removeViewerRow
- 删除死代码：imageUrl()（全项目无调用）；cinemas.php 配色数组中本就会被
  array_slice 丢弃的 extra 颜色逻辑，简化为单条扁平 50 元素数组
- README 目录结构补充 lib/ 说明

验证方式：以便携 PHP 8.4 搭建 A/B 回归环境，播种固定数据后遍历 47 个
GET/POST 端点录制「状态码 + 响应体」。重构前后 42 个逐字节相同、2 个仅
上传文件名时间戳不同、3 个差异均为内联脚本下沉（已单独校验函数体逐字符
等价，剥离脚本后 HTML 标记完全一致）。24 个 PHP 文件语法检查全部通过。

lib/stats.php

@@ -0,0 +1,329 @@
+<?php
+// ============================================
+// 文件: lib/stats.php
+// 说明: 统计仪表板与年度报告的查询逻辑
+// ============================================
+
+// ===== 统计 =====
+function getStatsOverview() {
+    $db = getDB();
+    $stats = [];
+    $stmt = $db->query("SELECT COUNT(*) FROM movies");
+    $stats['total_movies'] = $stmt->fetchColumn();
+    $stmt = $db->query("SELECT COUNT(*) FROM cinemas");
+    $stats['total_cinemas'] = $stmt->fetchColumn();
+    $stmt = $db->query("SELECT COUNT(*) FROM persons");
+    $stats['total_persons'] = $stmt->fetchColumn();
+    $stmt = $db->query("SELECT COUNT(*) FROM viewers");
+    $stats['total_viewership'] = $stmt->fetchColumn();
+    $stmt = $db->query("SELECT MIN(watch_date) as first, MAX(watch_date) as last FROM movies WHERE watch_date IS NOT NULL");
+    $row = $stmt->fetch();
+    $stats['first_date'] = $row['first'];
+    $stats['last_date'] = $row['last'];
+    return $stats;
+}
+
+function statsByCinema() {
+    $db = getDB();
+    $stmt = $db->query("
+        SELECT c.id, c.name, c.color, COUNT(m.id) as count
+        FROM cinemas c
+        LEFT JOIN movies m ON c.id = m.cinema_id
+        GROUP BY c.id
+        ORDER BY count DESC
+    ");
+    return $stmt->fetchAll();
+}
+
+function statsByPerson() {
+    $db = getDB();
+    $stmt = $db->query("
+        SELECT p.id, p.name, p.color, p.avatar, COUNT(v.movie_id) as count
+        FROM persons p
+        LEFT JOIN viewers v ON p.id = v.person_id
+        GROUP BY p.id
+        ORDER BY count DESC
+    ");
+    return $stmt->fetchAll();
+}
+
+function statsByMonth($limit = 12) {
+    $db = getDB();
+    $stmt = $db->prepare("
+        SELECT strftime('%Y-%m', watch_date) as month, COUNT(*) as count
+        FROM movies
+        WHERE watch_date IS NOT NULL
+        GROUP BY month
+        ORDER BY month DESC
+        LIMIT ?
+    ");
+    $stmt->execute([$limit]);
+    return $stmt->fetchAll();
+}
+
+function statsByYear() {
+    $db = getDB();
+    $stmt = $db->query("
+        SELECT strftime('%Y', watch_date) as year, COUNT(*) as count
+        FROM movies
+        WHERE watch_date IS NOT NULL
+        GROUP BY year
+        ORDER BY year DESC
+    ");
+    return $stmt->fetchAll();
+}
+
+// ===== 年度报告 =====
+function getAnnualStats($year) {
+    $db = getDB();
+    $stats = [];
+
+    // 获取当前管理员
+    $admin = getCurrentAdmin();
+    $self_person_id = $admin['person_id'] ?? null;
+    $stats['self_person_name'] = $admin['person_name'] ?? null;
+    $stats['self_person_avatar'] = $admin['person_avatar'] ?? null;
+
+    if (!$self_person_id) {
+        // 未关联观影人，返回空数据
+        $stats['total'] = 0;
+        $stats['days'] = 0;
+        $stats['top_cinema'] = '无';
+        $stats['top_cinema_count'] = 0;
+        $stats['top_person'] = '无';
+        $stats['top_person_count'] = 0;
+        $stats['first_date'] = null;
+        $stats['last_date'] = null;
+        $stats['most_viewers_movie'] = '无';
+        $stats['most_viewers_count'] = 0;
+        $stats['month_distribution'] = array_fill(1, 12, 0);
+        $stats['weekday_distribution'] = ['日'=>0,'一'=>0,'二'=>0,'三'=>0,'四'=>0,'五'=>0,'六'=>0];
+        $stats['avg_per_month'] = 0;
+        $stats['avg_days_between'] = 0;
+        $stats['keywords'] = [];
+        $stats['recent_movies'] = [];
+        $stats['my_movies'] = [];
+        $stats['common_viewers'] = [];
+        return $stats;
+    }
+
+    // 1. 总观影数（当前用户参与的电影）
+    $stmt = $db->prepare("
+        SELECT COUNT(DISTINCT m.id)
+        FROM movies m
+        JOIN viewers v ON m.id = v.movie_id
+        WHERE strftime('%Y', m.watch_date) = ?
+          AND v.person_id = ?
+    ");
+    $stmt->execute([$year, $self_person_id]);
+    $stats['total'] = (int)$stmt->fetchColumn();
+
+    // 2. 观影天数
+    $stmt = $db->prepare("
+        SELECT COUNT(DISTINCT m.watch_date)
+        FROM movies m
+        JOIN viewers v ON m.id = v.movie_id
+        WHERE strftime('%Y', m.watch_date) = ?
+          AND v.person_id = ?
+          AND m.watch_date IS NOT NULL
+    ");
+    $stmt->execute([$year, $self_person_id]);
+    $stats['days'] = (int)$stmt->fetchColumn();
+
+    // 3. 最常去的影院
+    $stmt = $db->prepare("
+        SELECT c.name, COUNT(m.id) as count
+        FROM movies m
+        JOIN viewers v ON m.id = v.movie_id
+        LEFT JOIN cinemas c ON m.cinema_id = c.id
+        WHERE strftime('%Y', m.watch_date) = ?
+          AND v.person_id = ?
+          AND m.cinema_id IS NOT NULL
+        GROUP BY m.cinema_id
+        ORDER BY count DESC LIMIT 1
+    ");
+    $stmt->execute([$year, $self_person_id]);
+    $top_cinema = $stmt->fetch();
+    $stats['top_cinema'] = $top_cinema ? $top_cinema['name'] : '无';
+    $stats['top_cinema_count'] = $top_cinema ? (int)$top_cinema['count'] : 0;
+
+    // 4. 最常一起观影的人（与当前用户同场最多的人）
+    // 先获取当前用户看过的所有电影ID
+    $stmt = $db->prepare("
+        SELECT DISTINCT m.id
+        FROM movies m
+        JOIN viewers v ON m.id = v.movie_id
+        WHERE strftime('%Y', m.watch_date) = ?
+          AND v.person_id = ?
+    ");
+    $stmt->execute([$year, $self_person_id]);
+    $movie_ids = $stmt->fetchAll(PDO::FETCH_COLUMN);
+
+    // 共同观影人统计
+    $common_viewers = [];
+    if (!empty($movie_ids)) {
+        $placeholders = implode(',', array_fill(0, count($movie_ids), '?'));
+        $params = array_merge($movie_ids, [$self_person_id]);
+        $stmt = $db->prepare("
+            SELECT p.id, p.name, p.avatar, COUNT(*) as count
+            FROM viewers v
+            JOIN persons p ON v.person_id = p.id
+            WHERE v.movie_id IN ($placeholders)
+              AND v.person_id != ?
+            GROUP BY v.person_id
+            ORDER BY count DESC
+        ");
+        $stmt->execute($params);
+        $common_viewers = $stmt->fetchAll();
+    }
+    $stats['common_viewers'] = $common_viewers;
+
+    // 最常一起观影的人（取第一个）
+    $stats['top_person'] = !empty($common_viewers) ? $common_viewers[0]['name'] : '无';
+    $stats['top_person_count'] = !empty($common_viewers) ? (int)$common_viewers[0]['count'] : 0;
+
+    // 5. 最早和最晚日期
+    $stmt = $db->prepare("
+        SELECT MIN(m.watch_date) as first, MAX(m.watch_date) as last
+        FROM movies m
+        JOIN viewers v ON m.id = v.movie_id
+        WHERE strftime('%Y', m.watch_date) = ?
+          AND v.person_id = ?
+          AND m.watch_date IS NOT NULL
+    ");
+    $stmt->execute([$year, $self_person_id]);
+    $row = $stmt->fetch();
+    $stats['first_date'] = $row['first'];
+    $stats['last_date'] = $row['last'];
+
+    // 6. 单次最多人的电影（当前用户参与的电影中）
+    $stmt = $db->prepare("
+        SELECT m.id, m.title, COUNT(v.id) as viewer_count
+        FROM movies m
+        JOIN viewers v ON m.id = v.movie_id
+        WHERE strftime('%Y', m.watch_date) = ?
+          AND m.id IN (SELECT movie_id FROM viewers WHERE person_id = ?)
+        GROUP BY m.id
+        ORDER BY viewer_count DESC LIMIT 1
+    ");
+    $stmt->execute([$year, $self_person_id]);
+    $most_viewers = $stmt->fetch();
+    $stats['most_viewers_movie'] = $most_viewers ? $most_viewers['title'] : '无';
+    $stats['most_viewers_count'] = $most_viewers ? (int)$most_viewers['viewer_count'] : 0;
+
+    // 7. 月份分布
+    $stmt = $db->prepare("
+        SELECT strftime('%m', m.watch_date) as month, COUNT(*) as count
+        FROM movies m
+        JOIN viewers v ON m.id = v.movie_id
+        WHERE strftime('%Y', m.watch_date) = ?
+          AND v.person_id = ?
+          AND m.watch_date IS NOT NULL
+        GROUP BY month
+        ORDER BY month
+    ");
+    $stmt->execute([$year, $self_person_id]);
+    $month_data = $stmt->fetchAll(PDO::FETCH_KEY_PAIR);
+    $stats['month_distribution'] = [];
+    for ($m=1; $m<=12; $m++) {
+        $key = str_pad($m, 2, '0', STR_PAD_LEFT);
+        $stats['month_distribution'][$m] = isset($month_data[$key]) ? (int)$month_data[$key] : 0;
+    }
+
+    // 8. 星期分布
+    $stmt = $db->prepare("
+        SELECT strftime('%w', m.watch_date) as wday, COUNT(*) as count
+        FROM movies m
+        JOIN viewers v ON m.id = v.movie_id
+        WHERE strftime('%Y', m.watch_date) = ?
+          AND v.person_id = ?
+          AND m.watch_date IS NOT NULL
+        GROUP BY wday
+        ORDER BY wday
+    ");
+    $stmt->execute([$year, $self_person_id]);
+    $wday_data = $stmt->fetchAll(PDO::FETCH_KEY_PAIR);
+    $weekdays = ['日','一','二','三','四','五','六'];
+    $stats['weekday_distribution'] = [];
+    foreach ($weekdays as $idx => $name) {
+        $stats['weekday_distribution'][$name] = isset($wday_data[$idx]) ? (int)$wday_data[$idx] : 0;
+    }
+
+    // 9. 月均和频率
+    $stats['avg_per_month'] = $stats['total'] > 0 ? round($stats['total'] / 12, 1) : 0;
+    $stats['avg_days_between'] = $stats['total'] > 0 ? round(365 / $stats['total'], 1) : 0;
+
+    // 10. 关键词（基于当前用户电影的备注）
+    $stmt = $db->prepare("
+        SELECT m.remark
+        FROM movies m
+        JOIN viewers v ON m.id = v.movie_id
+        WHERE strftime('%Y', m.watch_date) = ?
+          AND v.person_id = ?
+          AND m.remark IS NOT NULL
+          AND m.remark != ''
+    ");
+    $stmt->execute([$year, $self_person_id]);
+    $remarks = $stmt->fetchAll(PDO::FETCH_COLUMN);
+    $word_count = [];
+    foreach ($remarks as $text) {
+        $words = preg_split('/[\s，,。.！!？?、；;：:]+/', $text, -1, PREG_SPLIT_NO_EMPTY);
+        foreach ($words as $w) {
+            $w = trim($w);
+            if (mb_strlen($w) >= 2) {
+                if (!isset($word_count[$w])) $word_count[$w] = 0;
+                $word_count[$w]++;
+            }
+        }
+    }
+    arsort($word_count);
+    $stats['keywords'] = array_slice(array_keys($word_count), 0, 5);
+
+    // 11. 最近5部（当前用户参与的）
+    $stmt = $db->prepare("
+        SELECT DISTINCT m.title
+        FROM movies m
+        JOIN viewers v ON m.id = v.movie_id
+        WHERE strftime('%Y', m.watch_date) = ?
+          AND v.person_id = ?
+        ORDER BY m.watch_date DESC
+        LIMIT 5
+    ");
+    $stmt->execute([$year, $self_person_id]);
+    $stats['recent_movies'] = $stmt->fetchAll(PDO::FETCH_COLUMN);
+
+    // 12. 我的观影记录（含海报）
+    $stmt = $db->prepare("
+        SELECT m.id, m.title, m.watch_date, m.poster_path
+        FROM movies m
+        JOIN viewers v ON m.id = v.movie_id
+        WHERE strftime('%Y', m.watch_date) = ?
+          AND v.person_id = ?
+        GROUP BY m.id
+        ORDER BY m.watch_date DESC
+    ");
+    $stmt->execute([$year, $self_person_id]);
+    $movie_list = $stmt->fetchAll();
+
+    // 对每个电影查询一起观影的人（含头像）
+    foreach ($movie_list as &$movie) {
+        $stmt2 = $db->prepare("
+            SELECT p.id, p.name, p.avatar
+            FROM viewers v
+            LEFT JOIN persons p ON v.person_id = p.id
+            WHERE v.movie_id = ?
+              AND v.person_id != ?
+        ");
+        $stmt2->execute([$movie['id'], $self_person_id]);
+        $movie['viewers'] = $stmt2->fetchAll();
+    }
+    $stats['my_movies'] = $movie_list;
+
+    return $stats;
+}
+
+function getYearsWithData() {
+    $db = getDB();
+    $stmt = $db->query("SELECT DISTINCT strftime('%Y', watch_date) as year FROM movies WHERE watch_date IS NOT NULL ORDER BY year DESC");
+    return $stmt->fetchAll(PDO::FETCH_COLUMN);
+}