第一版提交，答题功能OK，题库管理待完善

api/database/index.ts

@@ -0,0 +1,185 @@
+import sqlite3 from 'sqlite3';
+import path from 'path';
+import fs from 'fs';
+
+const DEFAULT_DB_DIR = path.join(process.cwd(), 'data');
+const DEFAULT_DB_PATH = path.join(DEFAULT_DB_DIR, 'survey.db');
+
+const DB_PATH = process.env.DB_PATH || DEFAULT_DB_PATH;
+const DB_DIR = path.dirname(DB_PATH);
+
+// 确保数据目录存在
+if (!fs.existsSync(DB_DIR)) {
+  fs.mkdirSync(DB_DIR, { recursive: true });
+}
+
+// 创建数据库连接
+export const db = new sqlite3.Database(DB_PATH, (err) => {
+  if (err) {
+    console.error('数据库连接失败:', err);
+  } else {
+    console.log('数据库连接成功');
+  }
+});
+
+// 启用外键约束
+db.run('PRAGMA foreign_keys = ON');
+
+const exec = (sql: string): Promise<void> => {
+  return new Promise((resolve, reject) => {
+    db.exec(sql, (err) => {
+      if (err) reject(err);
+      else resolve();
+    });
+  });
+};
+
+const tableExists = async (tableName: string): Promise<boolean> => {
+  const row = await get(
+    "SELECT name FROM sqlite_master WHERE type='table' AND name=?",
+    [tableName]
+  );
+  return Boolean(row);
+};
+
+const columnExists = async (tableName: string, columnName: string): Promise<boolean> => {
+  const columns = await query(`PRAGMA table_info(${tableName})`);
+  return columns.some((col: any) => col.name === columnName);
+};
+
+const ensureColumn = async (tableName: string, columnDefSql: string, columnName: string) => {
+  if (!(await columnExists(tableName, columnName))) {
+    await exec(`ALTER TABLE ${tableName} ADD COLUMN ${columnDefSql}`);
+  }
+};
+
+const ensureTable = async (createTableSql: string) => {
+  await exec(createTableSql);
+};
+
+const ensureIndex = async (createIndexSql: string) => {
+  await exec(createIndexSql);
+};
+
+const migrateDatabase = async () => {
+  await ensureColumn('users', `password TEXT NOT NULL DEFAULT ''`, 'password');
+
+  await ensureColumn('questions', `category TEXT NOT NULL DEFAULT '通用'`, 'category');
+  await run(`UPDATE questions SET category = '通用' WHERE category IS NULL OR category = ''`);
+
+  await ensureTable(`
+    CREATE TABLE IF NOT EXISTS question_categories (
+      id TEXT PRIMARY KEY,
+      name TEXT UNIQUE NOT NULL,
+      created_at DATETIME DEFAULT CURRENT_TIMESTAMP
+    );
+  `);
+
+  await run(
+    `INSERT OR IGNORE INTO question_categories (id, name) VALUES ('default', '通用')`
+  );
+
+  await ensureTable(`
+    CREATE TABLE IF NOT EXISTS exam_subjects (
+      id TEXT PRIMARY KEY,
+      name TEXT UNIQUE NOT NULL,
+      type_ratios TEXT NOT NULL,
+      category_ratios TEXT NOT NULL,
+      total_score INTEGER NOT NULL,
+      duration_minutes INTEGER NOT NULL DEFAULT 60,
+      created_at DATETIME DEFAULT CURRENT_TIMESTAMP,
+      updated_at DATETIME DEFAULT CURRENT_TIMESTAMP
+    );
+  `);
+
+  await ensureTable(`
+    CREATE TABLE IF NOT EXISTS exam_tasks (
+      id TEXT PRIMARY KEY,
+      name TEXT NOT NULL,
+      subject_id TEXT NOT NULL,
+      start_at DATETIME NOT NULL,
+      end_at DATETIME NOT NULL,
+      created_at DATETIME DEFAULT CURRENT_TIMESTAMP,
+      FOREIGN KEY (subject_id) REFERENCES exam_subjects(id)
+    );
+  `);
+
+  await ensureTable(`
+    CREATE TABLE IF NOT EXISTS exam_task_users (
+      id TEXT PRIMARY KEY,
+      task_id TEXT NOT NULL,
+      user_id TEXT NOT NULL,
+      created_at DATETIME DEFAULT CURRENT_TIMESTAMP,
+      UNIQUE(task_id, user_id),
+      FOREIGN KEY (task_id) REFERENCES exam_tasks(id) ON DELETE CASCADE,
+      FOREIGN KEY (user_id) REFERENCES users(id) ON DELETE CASCADE
+    );
+  `);
+
+  if (await tableExists('quiz_records')) {
+    await ensureColumn('quiz_records', `subject_id TEXT`, 'subject_id');
+    await ensureColumn('quiz_records', `task_id TEXT`, 'task_id');
+  }
+
+  await ensureIndex(`CREATE INDEX IF NOT EXISTS idx_questions_category ON questions(category);`);
+  await ensureIndex(`CREATE INDEX IF NOT EXISTS idx_exam_tasks_subject_id ON exam_tasks(subject_id);`);
+  await ensureIndex(`CREATE INDEX IF NOT EXISTS idx_exam_task_users_task_id ON exam_task_users(task_id);`);
+  await ensureIndex(`CREATE INDEX IF NOT EXISTS idx_exam_task_users_user_id ON exam_task_users(user_id);`);
+  await ensureIndex(`CREATE INDEX IF NOT EXISTS idx_quiz_records_subject_id ON quiz_records(subject_id);`);
+  await ensureIndex(`CREATE INDEX IF NOT EXISTS idx_quiz_records_task_id ON quiz_records(task_id);`);
+};
+
+// 数据库初始化函数
+export const initDatabase = async () => {
+  const initSQL = fs.readFileSync(path.join(process.cwd(), 'api', 'database', 'init.sql'), 'utf8');
+
+  const hasUsersTable = await tableExists('users');
+  if (!hasUsersTable) {
+    await exec(initSQL);
+    console.log('数据库初始化成功');
+  } else {
+    console.log('数据库已初始化，准备执行迁移检查');
+  }
+
+  await migrateDatabase();
+};
+
+// 数据库查询工具函数
+export const query = (sql: string, params: any[] = []): Promise<any[]> => {
+  return new Promise((resolve, reject) => {
+    db.all(sql, params, (err, rows) => {
+      if (err) {
+        reject(err);
+      } else {
+        resolve(rows);
+      }
+    });
+  });
+};
+
+// all函数是query函数的别名，用于向后兼容
+export const all = query;
+
+export const run = (sql: string, params: any[] = []): Promise<{ id: string }> => {
+  return new Promise((resolve, reject) => {
+    db.run(sql, params, function(err) {
+      if (err) {
+        reject(err);
+      } else {
+        resolve({ id: this.lastID.toString() });
+      }
+    });
+  });
+};
+
+export const get = (sql: string, params: any[] = []): Promise<any> => {
+  return new Promise((resolve, reject) => {
+    db.get(sql, params, (err, row) => {
+      if (err) {
+        reject(err);
+      } else {
+        resolve(row);
+      }
+    });
+  });
+};