MovieLog_Server/lib/reviews.php

<?php
// ============================================
// 文件: lib/reviews.php
// 说明: 电影评价 + 评价下的讨论（评论）。
//
//       评价人是「登录账号」（admins），与观影人（persons / viewers）无关：
//       没一起去看这部电影的人，只要有账号，也能打分、写评价、参与讨论。
//
//       数据模型:
//         reviews           一部电影 × 一个账号 至多一条（rating 1-10 + 正文）
//         review_comments   挂在某条评价下的讨论；可带多个「观后感受」
//
//       观后感受只存 key（如 happy / sad），emoji 与文案统一在本文件的
//       feelingCatalog() 里维护，改文案 / 换 emoji 都不需要动数据库。
// ============================================

// 评价正文 / 评论正文的最大字数（UTF-8 字符数）
define('REVIEW_CONTENT_MAX', 5000);
define('REVIEW_COMMENT_MAX', 1000);
// 一条评论最多能选几种感受
define('REVIEW_FEELING_MAX', 6);

// ===== 观后感受目录 =====
// key => [emoji, 中文名]。评论时可多选，每种感受一个专属 emoji。
function feelingCatalog() {
    static $catalog = null;
    if ($catalog === null) {
        $catalog = [
            'happy'         => ['emoji' => '😄', 'label' => '开心'],
            'moved'         => ['emoji' => '🥹', 'label' => '感动'],
            'warm'          => ['emoji' => '🥰', 'label' => '温暖'],
            'excited'       => ['emoji' => '🤩', 'label' => '激动'],
            'thoughtful'    => ['emoji' => '🤔', 'label' => '深思'],
            'tense'         => ['emoji' => '😰', 'label' => '紧张'],
            'scared'        => ['emoji' => '😨', 'label' => '恐惧'],
            'surprised'     => ['emoji' => '😲', 'label' => '震惊'],
            'sad'           => ['emoji' => '😢', 'label' => '难受'],
            'angry'         => ['emoji' => '😠', 'label' => '气愤'],
            'bored'         => ['emoji' => '😴', 'label' => '无聊'],
            'confused'      => ['emoji' => '😵', 'label' => '困惑'],
        ];
    }
    return $catalog;
}

// 取某一种感受的 emoji + 文案；key 不存在时返回 null
function feelingInfo($key) {
    $catalog = feelingCatalog();
    return isset($catalog[$key]) ? $catalog[$key] : null;
}

// ===== 文本长度（按 UTF-8 字符计；没有 mbstring 时退化为字节数） =====
function reviewTextLength($str) {
    return function_exists('mb_strlen') ? mb_strlen((string)$str, 'UTF-8') : strlen((string)$str);
}

// ===== 感受的校验 / 存取 =====

// 把表单提交（数组）或库里取出的数组，整理成合法的感受 key 列表：
// 过滤不在目录里的值、去重、截断到上限，并保持目录里的顺序。
function normalizeFeelings($raw, $max = REVIEW_FEELING_MAX) {
    $catalog = feelingCatalog();
    $picked  = [];
    if (is_array($raw)) {
        foreach ($raw as $key) {
            $key = is_string($key) ? trim($key) : '';
            if ($key !== '' && isset($catalog[$key]) && !in_array($key, $picked, true)) {
                $picked[] = $key;
            }
        }
    }
    // 保持目录顺序，读出来展示时才不会跟着勾选顺序乱跳
    $ordered = [];
    foreach ($catalog as $key => $info) {
        if (in_array($key, $picked, true)) $ordered[] = $key;
    }
    return array_slice($ordered, 0, max(0, (int)$max));
}

// 解析库里 feelings 字段（JSON 数组字符串）→ 合法的 key 列表
function parseStoredFeelings($json) {
    if ($json === null || $json === '') return [];
    $keys = json_decode((string)$json, true);
    if (!is_array($keys)) return [];
    return normalizeFeelings($keys);
}

// 感受列表 → 入库用的 JSON 字符串
function feelingsToJson(array $keys) {
    return json_encode(array_values($keys), JSON_UNESCAPED_UNICODE);
}

// ===== 评分文案 =====
// 1-10 分给一句词，详情页打分时实时显示，评价列表里也用它做 title。
function ratingWord($rating) {
    $r = (int)$rating;
    if ($r <= 2) return '很失望';
    if ($r <= 4) return '不太行';
    if ($r <= 6) return '还行';
    if ($r <= 8) return '不错';
    return '很棒';
}

// ===== 读取 =====

// 某部电影的全部评价（新在前），并把讨论一次性挂到每条评价的 comments 上
function getMovieReviews($movie_id) {
    $db = getDB();
    $stmt = $db->prepare("
        SELECT r.*, a.username, a.avatar
        FROM reviews r
        LEFT JOIN admins a ON r.admin_id = a.id
        WHERE r.movie_id = ?
        ORDER BY r.created_at DESC, r.id DESC
    ");
    $stmt->execute([$movie_id]);
    $reviews = $stmt->fetchAll();
    foreach ($reviews as &$review) {
        // 评价本身带的观后感受（JSON 字符串 → key 列表）
        $review['feelings'] = parseStoredFeelings($review['feelings'] ?? '');
    }
    unset($review);
    attachCommentsToReviews($reviews);
    return $reviews;
}

// 给一批评价挂上 comments（一次查询，避免每条评价查一次库）
function attachCommentsToReviews(array &$reviews) {
    if (empty($reviews)) return;
    $ids = array_column($reviews, 'id');
    $ids = array_values(array_filter($ids, function ($v) { return (int)$v > 0; }));
    if (empty($ids)) return;

    $db = getDB();
    $placeholders = implode(',', array_fill(0, count($ids), '?'));
    $stmt = $db->prepare("
        SELECT c.*, a.username, a.avatar
        FROM review_comments c
        LEFT JOIN admins a ON c.admin_id = a.id
        WHERE c.review_id IN ($placeholders)
        ORDER BY c.created_at ASC, c.id ASC
    ");
    $stmt->execute($ids);

    $map = [];
    foreach ($stmt->fetchAll() as $row) {
        $row['feelings'] = parseStoredFeelings($row['feelings'] ?? '');
        $map[(int)$row['review_id']][] = $row;
    }
    foreach ($reviews as &$review) {
        $review['comments'] = $map[(int)$review['id']] ?? [];
    }
    unset($review);
}

// 当前账号在这部电影上的评价（没有则 null）
function getMyReview($movie_id, $admin_id) {
    if ((int)$admin_id <= 0) return null;
    $db = getDB();
    $stmt = $db->prepare("SELECT * FROM reviews WHERE movie_id = ? AND admin_id = ?");
    $stmt->execute([$movie_id, $admin_id]);
    $row = $stmt->fetch();
    if ($row) {
        $row['feelings'] = parseStoredFeelings($row['feelings'] ?? '');
    }
    return $row ?: null;
}

// 取单条评价（用于校验评论挂在的评价确实属于这部电影）
function getReviewById($review_id) {
    $db = getDB();
    $stmt = $db->prepare("SELECT * FROM reviews WHERE id = ?");
    $stmt->execute([$review_id]);
    $row = $stmt->fetch();
    return $row ?: null;
}

// 某部电影的评分概况：['count' => n, 'avg' => 7.5]
// 没人评价时 avg 为 null，展示时不要显示 0 分。
function reviewStats($movie_id) {
    $db = getDB();
    $stmt = $db->prepare("SELECT COUNT(*) AS c, AVG(rating) AS a FROM reviews WHERE movie_id = ?");
    $stmt->execute([$movie_id]);
    $row = $stmt->fetch();
    $count = (int)($row['c'] ?? 0);
    return [
        'count' => $count,
        'avg'   => $count > 0 ? round((float)$row['a'], 1) : null,
    ];
}

// 给电影列表批量挂上评分概况（列表页展示均分用，一次查询搞定）
function attachReviewStatsToMovies(array &$movies) {
    if (empty($movies)) return;
    $ids = array_values(array_unique(array_filter(array_column($movies, 'id'), function ($v) { return (int)$v > 0; })));
    if (empty($ids)) return;

    $db = getDB();
    $placeholders = implode(',', array_fill(0, count($ids), '?'));
    $stmt = $db->prepare("
        SELECT movie_id, COUNT(*) AS c, AVG(rating) AS a
        FROM reviews WHERE movie_id IN ($placeholders) GROUP BY movie_id
    ");
    $stmt->execute($ids);

    $map = [];
    foreach ($stmt->fetchAll() as $row) {
        $map[(int)$row['movie_id']] = [
            'count' => (int)$row['c'],
            'avg'   => round((float)$row['a'], 1),
        ];
    }
    foreach ($movies as &$movie) {
        $movie['review_count'] = $map[(int)$movie['id']]['count'] ?? 0;
        $movie['review_avg']   = $map[(int)$movie['id']]['avg'] ?? null;
    }
    unset($movie);
}

// ===== 写入 =====

/**
 * 发表 / 修改评价。一个账号对一部电影只保留一条：已有则更新，没有则插入。
 * $feelings 是评价人自己选的观后感受 key 数组（可以为空）。
 * 调用前请自行校验 rating 在 1-10、content 非空且未超长。
 * 成功返回 true。
 */
function saveReview($movie_id, $admin_id, $rating, $content, array $feelings = []) {
    $db = getDB();
    $rating   = (int)$rating;
    $content  = trim((string)$content);
    $feelings = normalizeFeelings($feelings);
    if ($rating < 1 || $rating > 10 || $content === '' || (int)$admin_id <= 0) {
        return false;
    }

    try {
        $db->beginTransaction();
        $stmt = $db->prepare("SELECT id FROM reviews WHERE movie_id = ? AND admin_id = ?");
        $stmt->execute([$movie_id, $admin_id]);
        $existing = $stmt->fetch();

        if ($existing) {
            $stmt = $db->prepare("
                UPDATE reviews SET rating = ?, content = ?, feelings = ?, updated_at = CURRENT_TIMESTAMP
                WHERE id = ?
            ");
            $stmt->execute([$rating, $content, feelingsToJson($feelings), $existing['id']]);
        } else {
            $stmt = $db->prepare("
                INSERT INTO reviews (movie_id, admin_id, rating, content, feelings)
                VALUES (?, ?, ?, ?, ?)
            ");
            $stmt->execute([$movie_id, $admin_id, $rating, $content, feelingsToJson($feelings)]);
        }
        $db->commit();
        return true;
    } catch (PDOException $e) {
        if ($db->inTransaction()) $db->rollBack();
        return false;
    }
}

// 删除自己的评价（连同下面的讨论一起删）。只能删自己的，删别人的返回 false。
function deleteReview($review_id, $admin_id) {
    $db = getDB();
    $stmt = $db->prepare("DELETE FROM reviews WHERE id = ? AND admin_id = ?");
    $stmt->execute([$review_id, $admin_id]);
    if ($stmt->rowCount() <= 0) return false;

    // 外键级联在本项目里没有开启（SQLite 默认关闭 PRAGMA foreign_keys），
    // 所以评论要手动清一遍，删掉评价后不能留下孤儿讨论。
    $stmt = $db->prepare("DELETE FROM review_comments WHERE review_id = ?");
    $stmt->execute([$review_id]);
    return true;
}

/**
 * 在一条评价下发表讨论。$feelings 是感受 key 数组（可为空）。
 * 返回新评论 id，失败返回 false。
 */
function addReviewComment($review_id, $admin_id, $content, array $feelings = []) {
    $db = getDB();
    $content = trim((string)$content);
    $review  = getReviewById($review_id);
    if (!$review || $content === '' || (int)$admin_id <= 0) {
        return false;
    }

    $stmt = $db->prepare("
        INSERT INTO review_comments (review_id, admin_id, content, feelings)
        VALUES (?, ?, ?, ?)
    ");
    $ok = $stmt->execute([
        $review_id,
        $admin_id,
        $content,
        feelingsToJson(normalizeFeelings($feelings)),
    ]);
    return $ok ? (int)$db->lastInsertId() : false;
}

// 删除自己的讨论；只能删自己的
function deleteReviewComment($comment_id, $admin_id) {
    $db = getDB();
    $stmt = $db->prepare("DELETE FROM review_comments WHERE id = ? AND admin_id = ?");
    $stmt->execute([$comment_id, $admin_id]);
    return $stmt->rowCount() > 0;
}

/**
 * 删除某部电影的全部评价与讨论（删电影时调用；级联未开启，需手动清）。
 *
 * $db 可以传入调用方已经打开的连接：delete.php 手里那条连接上还有没读完的
 * 游标（持有共享读锁），此时另开一条连接去 DELETE 会撞上 PDO 默认的
 * 60 秒 busy timeout，表现成「页面卡死」。复用同一条连接就不会互等。
 */
function deleteReviewsOfMovie($movie_id, $db = null) {
    if (!($db instanceof PDO)) {
        $db = getDB();
    }
    $stmt = $db->prepare("SELECT id FROM reviews WHERE movie_id = ?");
    $stmt->execute([$movie_id]);
    $ids = $stmt->fetchAll(PDO::FETCH_COLUMN);
    if (empty($ids)) return;

    $placeholders = implode(',', array_fill(0, count($ids), '?'));
    $stmt = $db->prepare("DELETE FROM review_comments WHERE review_id IN ($placeholders)");
    $stmt->execute($ids);
    $stmt = $db->prepare("DELETE FROM reviews WHERE movie_id = ?");
    $stmt->execute([$movie_id]);
}