-- 用户表
CREATE TABLE users (
    id TEXT PRIMARY KEY,
    name TEXT NOT NULL CHECK(length(name) >= 2 AND length(name) <= 20),
    phone TEXT UNIQUE NOT NULL CHECK(length(phone) = 11 AND phone LIKE '1%' AND substr(phone, 2, 1) BETWEEN '3' AND '9'),
    password TEXT NOT NULL DEFAULT '',
    created_at DATETIME DEFAULT CURRENT_TIMESTAMP
);

-- 创建用户表索引
CREATE INDEX idx_users_phone ON users(phone);
CREATE INDEX idx_users_created_at ON users(created_at);

-- 题目表
CREATE TABLE questions (
    id TEXT PRIMARY KEY,
    content TEXT NOT NULL,
    type TEXT NOT NULL CHECK(type IN ('single', 'multiple', 'judgment', 'text')),
    options TEXT, -- JSON格式存储选项
    answer TEXT NOT NULL,
    score INTEGER NOT NULL CHECK(score > 0),
    category TEXT NOT NULL DEFAULT '通用',
    created_at DATETIME DEFAULT CURRENT_TIMESTAMP
);

-- 创建题目表索引
CREATE INDEX idx_questions_type ON questions(type);
CREATE INDEX idx_questions_score ON questions(score);
CREATE INDEX idx_questions_category ON questions(category);

-- 题目类别表
CREATE TABLE question_categories (
    id TEXT PRIMARY KEY,
    name TEXT UNIQUE NOT NULL,
    created_at DATETIME DEFAULT CURRENT_TIMESTAMP
);

INSERT OR IGNORE INTO question_categories (id, name) VALUES ('default', '通用');

-- 考试科目表
CREATE TABLE 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
);

-- 考试任务表
CREATE TABLE 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)
);

CREATE INDEX idx_exam_tasks_subject_id ON exam_tasks(subject_id);

-- 考试任务参与用户表
CREATE TABLE 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
);

CREATE INDEX idx_exam_task_users_task_id ON exam_task_users(task_id);
CREATE INDEX idx_exam_task_users_user_id ON exam_task_users(user_id);

-- 答题记录表
CREATE TABLE quiz_records (
    id TEXT PRIMARY KEY,
    user_id TEXT NOT NULL,
    subject_id TEXT,
    task_id TEXT,
    total_score INTEGER NOT NULL,
    correct_count INTEGER NOT NULL,
    total_count INTEGER NOT NULL,
    created_at DATETIME DEFAULT CURRENT_TIMESTAMP,
    FOREIGN KEY (user_id) REFERENCES users(id),
    FOREIGN KEY (subject_id) REFERENCES exam_subjects(id),
    FOREIGN KEY (task_id) REFERENCES exam_tasks(id)
);

-- 创建答题记录表索引
CREATE INDEX idx_quiz_records_user_id ON quiz_records(user_id);
CREATE INDEX idx_quiz_records_created_at ON quiz_records(created_at);
CREATE INDEX idx_quiz_records_subject_id ON quiz_records(subject_id);
CREATE INDEX idx_quiz_records_task_id ON quiz_records(task_id);

-- 答题答案表
CREATE TABLE quiz_answers (
    id TEXT PRIMARY KEY,
    record_id TEXT NOT NULL,
    question_id TEXT NOT NULL,
    user_answer TEXT NOT NULL,
    score INTEGER NOT NULL,
    is_correct BOOLEAN NOT NULL,
    created_at DATETIME DEFAULT CURRENT_TIMESTAMP,
    FOREIGN KEY (record_id) REFERENCES quiz_records(id),
    FOREIGN KEY (question_id) REFERENCES questions(id)
);

-- 创建答题答案表索引
CREATE INDEX idx_quiz_answers_record_id ON quiz_answers(record_id);
CREATE INDEX idx_quiz_answers_question_id ON quiz_answers(question_id);

-- 系统配置表
CREATE TABLE system_configs (
    id TEXT PRIMARY KEY,
    config_type TEXT UNIQUE NOT NULL,
    config_value TEXT NOT NULL,
    updated_at DATETIME DEFAULT CURRENT_TIMESTAMP
);

-- 初始化抽题配置
INSERT INTO system_configs (id, config_type, config_value) VALUES 
('1', 'quiz_config', '{"singleRatio":40,"multipleRatio":30,"judgmentRatio":20,"textRatio":10,"totalScore":100}');

-- 初始化管理员账号
INSERT INTO system_configs (id, config_type, config_value) VALUES 
('2', 'admin_user', '{"username":"admin","password":"admin123"}');