"""
Migration: uapi table apisetid -> upappid

Removes uapiset intermediate layer. Each upapp now owns its own uapi records.
For shared apisetid: copies uapi records so each upapp has its own copy.

Usage (in Sage virtual env):
    ./py3/bin/python3 ~/repos/uapi/scripts/migrate_uapi_upappid.py --output /tmp/migrate_uapi.sql

Review the output SQL, then execute on your database.
"""
from appPublic.getConfig import getConfig
import asyncio, json, sys, argparse
from sqlor.dbpools import DBPools
from appPublic.uniqueID import getID

config = getConfig('.')
db = DBPools(config.databases)
dbname = list(config.databases.keys())[0]


async def generate_migration_sql():
    """Generate SQL to migrate uapi.apisetid -> uapi.upappid."""
    lines = [
        "-- Migration: uapi table apisetid -> upappid",
        "-- Removes uapiset intermediate layer.",
        "-- Each upapp owns its own uapi records after migration.",
        "",
        "-- Step 1: Add upappid column to uapi",
        "ALTER TABLE uapi ADD COLUMN upappid VARCHAR(21) DEFAULT NULL COMMENT '上位系统ID' AFTER id;",
        ""
    ]

    # Load data
    async with db.sqlorContext(dbname) as sor:
        # Get all upapps
        upapps = await sor.sqlExe('select id, name, apisetid from upapp', {})
        # Get all uapis
        uapis = await sor.sqlExe('select id, apisetid, name, httpmethod, path, headers, ioid, auth_apiname, response, params, data, chunk_match from uapi', {})

    # Build mapping: apisetid -> [upapp1, upapp2, ...]
    apiset_to_upapps = {}
    for u in upapps:
        aid = u.get('apisetid')
        if aid:
            apiset_to_upapps.setdefault(aid, []).append(u)

    # Build mapping: apisetid -> [uapi_records]
    apiset_to_uapis = {}
    for a in uapis:
        aid = a.get('apisetid')
        if aid:
            apiset_to_uapis.setdefault(aid, []).append(a)

    inserts = []
    for apisetid, upapp_list in apiset_to_upapps.items():
        uapi_records = apiset_to_uapis.get(apisetid, [])
        
        if len(upapp_list) == 1:
            # Single upapp owns this apisetid -> just update
            upapp = upapp_list[0]
            for uapi in uapi_records:
                inserts.append(
                    f"UPDATE uapi SET upappid = '{upapp['id']}' WHERE id = '{uapi['id']}';"
                )
        else:
            # Multiple upapps share this apisetid -> pick first as owner, copy for rest
            owner = upapp_list[0]
            
            # Update existing records to point to owner
            for uapi in uapi_records:
                inserts.append(
                    f"UPDATE uapi SET upappid = '{owner['id']}' WHERE id = '{uapi['id']}';"
                )
            
            # Copy for other upapps
            for other_upapp in upapp_list[1:]:
                for uapi in uapi_records:
                    new_id = getID()
                    old_id = uapi['id']
                    fields = ['id', 'upappid', 'name', 'httpmethod', 'path', 'headers', 'ioid', 'response', 'params', 'data', 'chunk_match']
                    vals = [f"'{new_id}'", f"'{other_upapp['id']}'"]
                    for f in fields[2:]:
                        v = uapi.get(f)
                        if v is None:
                            vals.append('NULL')
                        elif isinstance(v, str):
                            escaped = v.replace("'", "\\'")
                            vals.append(f"'{escaped}'")
                        else:
                            vals.append(str(v))
                    col_str = ', '.join(fields)
                    val_str = ', '.join(vals)
                    inserts.append(f"INSERT INTO uapi ({col_str}) VALUES ({val_str});")

    if inserts:
        lines.append("-- Step 2: Migrate data (updates + copies for shared apisetid)")
        lines.extend(inserts)
        lines.append("")

    lines.extend([
        "-- Step 3: Drop apisetid column (verify upappid has no NULLs first)",
        "-- UPDATE uapi SET upappid = (SELECT ownerid FROM organization LIMIT 1) WHERE upappid IS NULL;",
        "-- ALTER TABLE uapi DROP COLUMN apisetid;",
        "",
        "-- Step 4: Add index",
        "CREATE INDEX idx_uapi_upappid ON uapi (upappid);",
        ""
    ])
    
    return '\n'.join(lines)


async def main():
    parser = argparse.ArgumentParser()
    parser.add_argument('--output', '-o', default='-')
    args = parser.parse_args()
    
    sql = await generate_migration_sql()
    
    if args.output == '-':
        print(sql)
    else:
        with open(args.output, 'w', encoding='utf-8') as f:
            f.write(sql)
        print(f"Generated migration SQL -> {args.output}")


if __name__ == '__main__':
    asyncio.run(main())