import pandas as pd
from sqlalchemy import create_engine, inspect

cfg = {
    'csv_file': 'CARLO.csv',
    'clients': {'1': 'M und S Fahrzeughandel GmbH'},
    'filter': {'01.01.2018', '2019-01-01'},
    'source_dsn': {'user': 'sa', 'pass': 'Mffu3011#', 'server': 'GC-SERVER1\\GLOBALCUBE', 'database': 'DE0017', 'schema': 'dbo'},
    'target_dsn': {'user': 'sa', 'pass': 'Mffu3011#', 'server': 'GC-SERVER1\\GLOBALCUBE', 'database': 'CARLO2', 'schema': 'import'},
    'stage_dir': 'C:\\GlobalCube\\System\\CARLO\\Export\\stage'
}


def db_import(select_query, source_db, current_table, target_db, target_schema):
    pd.read_sql(select_query, source_db).to_sql(current_table['target'], target_db, schema=target_schema, index=False, if_exists='append')


def conn_string(dsn):
    return f"mssql+pyodbc://{dsn['user']}:{dsn['pass']}@{dsn['server']}/{dsn['database']}?driver=SQL+Server+Native+Client+11.0"


def conn_params(dsn):
    return f"-S {dsn['server']} -d {dsn['database']} -U {dsn['user']} -P {dsn['pass']}"


df = pd.read_csv(cfg['csv_file'], sep=';', encoding='latin-1')
config = df[df['target'].notnull()]
print(config.head())

source_db = create_engine(conn_string(cfg['source_dsn']))
source_insp = inspect(source_db)
source_tables = source_insp.get_table_names(schema=cfg['source_dsn']['schema'])
source_tables_prefix = set([t.split('$')[0] for t in source_tables if '$' in t])
print(source_tables_prefix)

target_db = create_engine(conn_string(cfg['target_dsn']))
target_insp = inspect(target_db)
target_tables = target_insp.get_table_names(schema=cfg['target_dsn']['schema'])


for index, current_table in config.iterrows():
    with open(cfg['stage_dir'] + "\\batch\\" + current_table['target'] + ".bat", "w", encoding="cp850") as f:
        f.write("@echo off \n")
        f.write("rem ==" + current_table['target'] + "==\n")

        if not current_table['target'] in target_tables:
            f.write(f"echo Ziel-Tabelle '{current_table['target']}' existiert nicht!\n")
            continue

        f.write(f"del {cfg['stage_dir']}\\{current_table['target']}*.* /Q /F >nul 2>nul \n")
        f.write(f"sqlcmd.exe {conn_params(cfg['target_dsn'])} -p " +
                f"-Q \"TRUNCATE TABLE [{cfg['target_dsn']['schema']}].[{current_table['target']}]\" \n")

        target_insp_cols = target_insp.get_columns(current_table['target'], schema=cfg['target_dsn']['schema'])
        target_columns_list = [col['name'] for col in target_insp_cols]
        target_columns = set(target_columns_list)

        for client_db, prefix in cfg['clients'].items():
            source_table = current_table['source'].format(prefix)

            if source_table not in source_tables:
                f.write(f"echo Quell-Tabelle '{source_table}' existiert nicht!\n")
                continue
            stage_csv = f"{cfg['stage_dir']}\\{current_table['target']}_{client_db}.csv"

            if not pd.isnull(current_table['query']):
                select_query = current_table['query'].format(prefix, cfg['filter'][0], cfg['filter'][1])
            else:
                select_query = f"SELECT T1.* FROM [{cfg['source_dsn']['schema']}].[{source_table}] T1 "

            if not pd.isnull(current_table['filter']):
                select_query += " WHERE " + current_table['filter'].format("", cfg['filter'][0], cfg['filter'][1])

            source_insp_cols = source_insp.get_columns(source_table)
            source_columns = set([col['name'] for col in source_insp_cols])

            intersect = source_columns.intersection(target_columns)
            # print("Auf beiden Seiten: " + ";".join(intersect))
            diff1 = source_columns.difference(target_columns)
            if len(diff1) > 0:
                f.write("rem Nur in Quelle: " + ";".join(diff1) + "\n")
            diff2 = target_columns.difference(source_columns)
            if "Client_DB" not in diff2:
                f.write("echo Spalte 'Client_DB' fehlt!\n")
                continue
            diff2.remove("Client_DB")
            if len(diff2) > 0:
                f.write("rem Nur in Ziel:   " + ";".join(diff2) + "\n")

            # select_columns = "T1.[" + "], T1.[".join(intersect) + "],"
            select_columns = ""
            for col in target_columns_list:
                if col in intersect:
                    select_columns += "T1.[" + col + "], "
                elif col == "Client_DB":
                    select_columns += "'" + client_db + "' as \\\"Client_DB\\\", "
                else:
                    select_columns += "'' as \\\"" + col + "\\\", "

            select_query = select_query.replace("T1.*", select_columns[:-2])
            select_query = select_query.replace("%", "%%")    # batch-Problem
            # print(select_query)
            f.write(f"bcp \"{select_query}\" queryout \"{stage_csv}\" {conn_params(cfg['source_dsn'])} " +
                    f"-c -C 65001 -e \"{stage_csv[:-4]}.queryout.log\" > \"{stage_csv[:-4]}.bcp1.log\" \n")
            f.write(f"type \"{stage_csv[:-4]}.bcp1.log\" | findstr -v \"1000\" \n")
            f.write(f"bcp [{cfg['target_dsn']['schema']}].[{current_table['target']}] in \"{stage_csv}\" " +
                    f"-c -C 65001 {conn_params(cfg['target_dsn'])} -e \"{stage_csv[:-4]}.in.log\" > \"{stage_csv[:-4]}.bcp2.log\" \n")
            f.write(f"type \"{stage_csv[:-4]}.bcp2.log\" | findstr -v \"1000\" \n")


with open(cfg['stage_dir'] + "\\batch\\_all.bat", "w", encoding="cp850") as f:
    f.write("@echo off & cd /d %~dp0 \n")
    f.write(f"del {cfg['stage_dir']}\\*.* /Q /F >nul 2>nul \n\n")
    for index, current_table in config.iterrows():
        f.write("echo ==" + current_table['target'] + "==\n")
        f.write("echo " + current_table['target'] + " >CON \n")
        f.write("call " + current_table['target'] + ".bat\n\n")