# -*- coding: utf-8 -*-
"""
测试 ODS 回填特性
"""
import os
import sys
from pathlib import Path

project_root = Path(__file__).parent.parent / "etl_billiards"
sys.path.insert(0, str(project_root))

from dotenv import load_dotenv
load_dotenv(project_root / ".env")

from database.connection import DatabaseConnection

dsn = os.getenv("PG_DSN")
db = DatabaseConnection(dsn)

print("=== 测试 ODS 回填特性 ===")

# 1. 创建一个测试场景：找一条有 NULL 值的记录
result = db.query("""
    SELECT id, plcouponsaleamount, mervousalesamount, 
           payload->'settleList'->>'plCouponSaleAmount' as payload_val
    FROM billiards_ods.settlement_records
    WHERE plcouponsaleamount IS NOT NULL
    LIMIT 1
""")

if result:
    row = result[0]
    print(f"找到测试记录: id={row['id']}")
    print(f"  当前 plcouponsaleamount: {row['plcouponsaleamount']}")
    print(f"  payload 中的值: {row['payload_val']}")
else:
    print("未找到测试记录")

# 2. 模拟生成的 SQL 语句
print("\n=== 生成的 SQL 示例 ===")

# 获取表结构
cols = db.query("""
    SELECT column_name 
    FROM information_schema.columns 
    WHERE table_schema = 'billiards_ods' 
      AND table_name = 'settlement_records'
    ORDER BY ordinal_position
""")

col_names = [c["column_name"] for c in cols]
pk_cols = ["id"]  # 假设主键是 id

meta_cols = {"payload", "source_file", "source_endpoint", "fetched_at", "content_hash"}
pk_cols_lower = {c.lower() for c in pk_cols}
update_cols = [
    c for c in col_names
    if c.lower() not in pk_cols_lower and c.lower() not in meta_cols
]

print(f"表有 {len(col_names)} 列")
print(f"可更新列: {len(update_cols)} 列")

# 生成 SQL
table = "billiards_ods.settlement_records"
pk_clause = ", ".join(f'"{c}"' for c in pk_cols)
set_clause = ", ".join(
    f'"{c}" = COALESCE({table}."{c}", EXCLUDED."{c}")'
    for c in update_cols[:3]  # 只显示前3个
)
where_clause = " OR ".join(f'{table}."{c}" IS NULL' for c in update_cols[:3])

print(f"\nSQL 示例 (前3列):")
print(f"INSERT INTO {table} (...) VALUES ...")
print(f"ON CONFLICT ({pk_clause}) DO UPDATE SET")
print(f"  {set_clause}")
print(f"WHERE {where_clause}")

print("\n=== 特性说明 ===")
print("1. 新记录 -> 正常插入")
print("2. 已存在记录 -> 只更新 NULL 列 (COALESCE)")
print("3. 已有值的列 -> 保持不变")
print("4. 可通过配置 run.ods_backfill_null_columns=false 禁用")

db.close()
print("\n测试完成!")