# -*- coding: utf-8 -*-
"""检查 DWD 维度表 SCD2 配置"""
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("=" * 70)
print("DWD Dimension Tables - SCD2 Analysis")
print("=" * 70)

# 获取所有维度表
tables = db.query("""
    SELECT table_name 
    FROM information_schema.tables 
    WHERE table_schema = 'billiards_dwd' 
      AND table_name LIKE 'dim_%'
    ORDER BY table_name
""")

scd_cols = {"scd2_start_time", "scd2_end_time", "scd2_is_current", "scd2_version"}

scd2_tables = []
type1_tables = []

for t in tables:
    tbl = t["table_name"]
    cols = db.query("""
        SELECT column_name FROM information_schema.columns
        WHERE table_schema = 'billiards_dwd' AND table_name = %s
    """, (tbl,))
    col_names = {c["column_name"].lower() for c in cols}
    
    has_scd = col_names & scd_cols
    if has_scd:
        scd2_tables.append((tbl, has_scd))
    else:
        type1_tables.append(tbl)

print("\n[SCD2 Tables - History Tracking]")
print("-" * 50)
if scd2_tables:
    for tbl, cols in scd2_tables:
        print(f"  {tbl}")
        print(f"    SCD2 cols: {', '.join(sorted(cols))}")
else:
    print("  (none)")

print(f"\n[Type1 Tables - Direct Overwrite] ({len(type1_tables)} tables)")
print("-" * 50)
for tbl in type1_tables:
    print(f"  {tbl}")

print("\n" + "=" * 70)
print("Processing Logic")
print("=" * 70)
print("""
Code path in dwd_load_task.py:

  if table.startswith('dim_'):
      _merge_dim()
        |
        +-- if has SCD2 columns:
        |       _merge_dim_scd2()
        |       -> Compare data, close old version, insert new version
        |       -> Uses INSERT (no ON CONFLICT)
        |       -> SCD2 NOT affected by fact_upsert config
        |
        +-- else:
                _merge_dim_type1_upsert()
                -> Uses ON CONFLICT DO UPDATE
                -> Direct overwrite (Type1)
  else:
      _load_fact_generic()
      -> Uses ON CONFLICT DO UPDATE (if fact_upsert=true)

CONCLUSION: SCD2 logic is INDEPENDENT, NOT affected by conflict mode settings.
""")

db.close()