#!/usr/bin/env python3
"""
初始化SQLite数据库并导入CSV数据
"""
import sqlite3
import csv
from pathlib import Path
from datetime import datetime

DB_PATH = "data/customs_data.db"
CSV_PATH = "data/standard_trade_records_sample.csv"

def create_database():
    """创建SQLite数据库和表结构"""
    print(f"创建数据库: {DB_PATH}")
    
    # 确保data目录存在
    Path("data").mkdir(exist_ok=True)
    
    conn = sqlite3.connect(DB_PATH)
    cursor = conn.cursor()
    
    # 删除旧表（如果存在）
    cursor.execute("DROP TABLE IF EXISTS standard_trade_records")
    
    # 创建标准贸易记录表
    cursor.execute("""
        CREATE TABLE standard_trade_records (
            record_id TEXT PRIMARY KEY,
            source_record_id TEXT NOT NULL,
            batch_no TEXT NOT NULL,
            source_country TEXT NOT NULL,
            trade_direction TEXT NOT NULL,
            trade_date TEXT NOT NULL,
            importer_name TEXT,
            exporter_name TEXT,
            hs_code TEXT,
            product_name TEXT,
            amount REAL,
            currency TEXT,
            weight REAL,
            weight_unit TEXT,
            origin_country TEXT,
            destination_country TEXT,
            departure_port TEXT,
            arrival_port TEXT,
            transport_mode TEXT,
            created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
            updated_at TIMESTAMP
        )
    """)
    
    # 创建索引
    cursor.execute("CREATE INDEX IF NOT EXISTS idx_source_country ON standard_trade_records(source_country)")
    cursor.execute("CREATE INDEX IF NOT EXISTS idx_trade_date ON standard_trade_records(trade_date)")
    cursor.execute("CREATE INDEX IF NOT EXISTS idx_hs_code ON standard_trade_records(hs_code)")
    cursor.execute("CREATE INDEX IF NOT EXISTS idx_trade_direction ON standard_trade_records(trade_direction)")
    
    conn.commit()
    return conn

def import_csv_data(conn):
    """从CSV导入数据"""
    print(f"导入CSV数据: {CSV_PATH}")
    
    if not Path(CSV_PATH).exists():
        print(f"警告: CSV文件不存在 {CSV_PATH}")
        return
    
    cursor = conn.cursor()
    
    # 先清空旧数据
    cursor.execute("DELETE FROM standard_trade_records")
    conn.commit()
    print("清空旧数据")
    
    with open(CSV_PATH, 'r', encoding='utf-8') as f:
        reader = csv.DictReader(f)
        count = 0
        batch = []
        
        for row in reader:
            # 处理日期：确保有效的日期格式，避免空字符串
            raw_date = row['trade_date'].strip() if row['trade_date'] else ''
            if not raw_date:
                trade_date = '2020-01-01'  # 默认日期
            else:
                # 去掉时间部分，只保留日期
                trade_date = raw_date.split(' ')[0] if ' ' in raw_date else raw_date
            
            batch.append((
                row['record_id'],
                row['source_record_id'],
                row['batch_no'],
                row['source_country'],
                row['trade_direction'],
                trade_date,
                row['importer_name'] or None,
                row['exporter_name'] or None,
                row['hs_code'] or None,
                row['product_name'] or None,
                float(row['amount']) if row['amount'] else None,
                row['currency'] or None,
                float(row['weight']) if row['weight'] else None,
                row['weight_unit'] or None,
                row['origin_country'] or None,
                row['destination_country'] or None,
                row['departure_port'] or None,
                row['arrival_port'] or None,
                row['transport_mode'] or None,
                row['created_at'],
                row.get('updated_at')
            ))
            
            count += 1
            
            # 每1000条批量插入
            if len(batch) >= 1000:
                cursor.executemany("""
                    INSERT INTO standard_trade_records VALUES (
                        ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?
                    )
                """, batch)
                conn.commit()
                print(f"已导入 {count} 条记录...")
                batch = []
        
        # 插入剩余数据
        if batch:
            cursor.executemany("""
                INSERT INTO standard_trade_records VALUES (
                    ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?
                )
            """, batch)
            conn.commit()
    
    print(f"总共导入 {count} 条记录")

def main():
    """主函数"""
    print("=== 初始化SQLite数据库 ===\n")
    
    conn = create_database()
    import_csv_data(conn)
    
    # 验证数据
    cursor = conn.cursor()
    cursor.execute("SELECT COUNT(*) FROM standard_trade_records")
    total = cursor.fetchone()[0]
    print(f"\n数据库中共有 {total} 条记录")
    
    cursor.execute("SELECT COUNT(*) FROM standard_trade_records WHERE source_country='BR'")
    br_count = cursor.fetchone()[0]
    print(f"巴西数据: {br_count} 条")
    
    conn.close()
    print("\n✅ 数据库初始化完成！")

if __name__ == "__main__":
    main()