import io
import json
import os
from dataclasses import dataclass, field
from functools import cached_property
from pathlib import Path

import pandas as pd
import pyodbc
from sqlalchemy import Engine, MetaData, create_engine


@dataclass
class DsnConfig:
    user: str = "sa"
    password: str = "Mffu3011#"
    server: str = "LOCALHOST\\GLOBALCUBE"
    database: str = "CARLO"
    driver: str = "mssql"
    schema: str = "import"

    def conn_ini(self, db_type: str) -> str:
        return "\n".join(
            [
                f'{db_type}_SERVER="{self.server}"',
                f'{db_type}_USER="{self.user}"',
                f'{db_type}_PASSWORD="{self.password}"',
                f'{db_type}_DATABASE="{self.database}"',
            ]
        )


class DatabaseInspect:
    _cursor: pyodbc.Cursor = None
    _sqlalchemy_engine: Engine = None

    def __init__(self, dsn: DsnConfig, source=False):
        self.dsn = dsn
        self.type = "SOURCE" if source else "DEST"

    @property
    def conn_string(self) -> str:
        if self.dsn.driver == "mssql":
            return ";".join(
                [
                    "Driver={SQL Server Native Client 11.0}",
                    f"Server={self.dsn.server}",
                    f"Database={self.dsn.database}",
                    f"Uid={self.dsn.user}",
                    f"Pwd={self.dsn.password}",
                ]
            )
        if self.dsn.driver == "mysql":
            return f"mysql+pymysql://{self.dsn.user}:{self.dsn.password}@{self.dsn.server}/{self.dsn.database}?charset=utf8mb4"
        return ";".join(
            [
                "Driver={PostgreSQL Unicode}",
                f"Server={self.dsn.server}",
                "Port=5432",
                f"Database={self.dsn.database}",
                f"Uid={self.dsn.user}",
                f"Pwd={self.dsn.password}",
            ]
        )
        # f"DSN={self.dsn.server};UID={self.dsn.user};PWD={self.dsn.password}"

    @property
    def conn_string_sqlalchemy(self) -> str:
        if self.dsn.driver == "mssql":
            return (
                f"mssql+pyodbc://{self.dsn.user}:{self.dsn.password}@{self.dsn.server}/{self.dsn.database}?"
                "driver=SQL+Server+Native+Client+11.0"
            )
        if self.dsn.driver == "mysql":
            return f"mysql+pymysql://{self.dsn.user}:{self.dsn.password}@{self.dsn.server}/{self.dsn.database}?charset=utf8mb4"
        return f"pyodbc://{self.dsn.user}:{self.dsn.password}@{self.dsn.server}/{self.dsn.database}?driver={self.dsn.driver}"

    @property
    def bcp_conn_params(self) -> str:
        return f"-S {self.dsn.server} -d {self.dsn.database} -U {self.dsn.user} -P {self.dsn.password}"

    @property
    def cursor(self) -> pyodbc.Cursor:
        if not self._cursor:
            self._cursor = self.connect()
        return self._cursor

    @property
    def sqlalchemy_engine(self) -> Engine:
        if not self._sqlalchemy_engine:
            self._sqlalchemy_engine = create_engine(self.conn_string_sqlalchemy)
        return self._sqlalchemy_engine

    def connect(self) -> pyodbc.Cursor:
        c = pyodbc.connect(self.conn_string)
        return c.cursor()

    @cached_property
    def tables_list(self) -> list[str]:
        tables = [x[2] for x in self.cursor.tables(tableType="TABLE")]
        views = [x[2] for x in self.cursor.tables(tableType="VIEW")]
        return tables + views

    def get_prefix(self) -> dict[str, str]:
        source_tables_prefix = dict(
            enumerate(sorted(list(set([t.split("$")[0] for t in self.tables_list if "$" in t]))), 1)
        )
        if len(source_tables_prefix) == 0:
            q = self.cursor.execute("select name FROM sys.databases")
            source_tables_prefix = [x[0] for x in q.fetchall()]
        return source_tables_prefix

    def get_columns(self, table: str) -> list[str]:
        source_insp_cols = [col.column_name for col in self.cursor.columns(table=table)]
        if len(source_insp_cols) == 0:
            q = self.cursor.execute(
                "SELECT COLUMN_NAME as column_name FROM information_schema.columns "
                + f"WHERE TABLE_NAME = '{self.convert_table(table)}'"
            )
            source_insp_cols = [col[0] for col in q.fetchall()]
        return source_insp_cols

    def get_columns_is_typeof_str(self, table: str) -> list[str]:
        source_insp_cols = [
            col.data_type in [pyodbc.SQL_CHAR, pyodbc.SQL_VARCHAR] for col in self.cursor.columns(table=table)
        ]
        if len(source_insp_cols) == 0:
            q = self.cursor.execute(
                "SELECT COLLATION_NAME as column_collation FROM information_schema.columns "
                + f"WHERE TABLE_NAME = '{self.convert_table(table)}'"
            )
            source_insp_cols = [len(col[0]) > 0 for col in q.fetchall()]
        return source_insp_cols

    def get_pkey(self, table: str, catalog: str) -> list[str]:
        source_insp_cols = [col.column_name for col in self.cursor.primaryKeys(table=table, catalog=catalog)]
        if len(source_insp_cols) == 0:
            self.cursor.execute(f"USE {catalog}")
            q = self.cursor.execute(
                "SELECT COLUMN_NAME "
                "FROM INFORMATION_SCHEMA.KEY_COLUMN_USAGE "
                "WHERE OBJECTPROPERTY(OBJECT_ID(CONSTRAINT_SCHEMA + '.' + QUOTENAME(CONSTRAINT_NAME)), 'IsPrimaryKey') = 1 "
                f"AND TABLE_NAME = '{self.convert_table(table)}' "  # AND TABLE_SCHEMA = 'dbo'"
            )
            source_insp_cols = [col[0] for col in q.fetchall()]
            self.cursor.execute(f"USE {self.dsn.database}")
        return source_insp_cols

    def convert_table(self, table: str) -> str:
        if "." in table:
            table = table.split(".")[-1]
        if "[" in table:
            table = table[1:-1]
        return table


@dataclass
class DbCreateConfig:
    name: str = "CARLO"
    csv_file: str = "..\\config\\CARLO.csv"
    clients: dict[str, str] = field(default_factory=lambda: {"1": "M und S Fahrzeughandel GmbH"})
    filter: list[str] = (["2018-01-01T00:00:00", "2022-01-01T00:00:00"],)
    source_dsn: DsnConfig = None
    dest_dsn: DsnConfig = None
    temp_db: str = "CARLOX"
    stage_dir: str = "..\\temp"
    batch_dir: str = "..\\batch"
    logs_dir: str = "..\\logs"
    scripts_dir: str = "C:\\GlobalCube\\Tasks\\scripts"

    source_inspect: DatabaseInspect = None
    dest_inspect: DatabaseInspect = None

    _sqlalchemy_engine: Engine = None

    @property
    def conn_ini(self) -> str:
        return "\n".join(
            [
                f'SQL_TEMP="{self.stage_dir}"',
                f'SQL_BATCH="{self.batch_dir}"',
                f'SQL_LOGS="{self.logs_dir}"',
            ]
        )

    @property
    def temp_db_sqlalchemy_engine(self) -> Engine:
        if not self._sqlalchemy_engine:
            self._sqlalchemy_engine = create_engine(
                f"mssql+pyodbc://{self.dest_dsn.user}:{self.dest_dsn.password}@{self.dest_dsn.server}/{self.temp_db}?"
                "driver=SQL+Server+Native+Client+11.0"
            )
            source_meta = MetaData()
            source_meta.reflect(bind=self._sqlalchemy_engine, schema="temp")
        return self._sqlalchemy_engine

    @staticmethod
    def load_config(config_file: str):
        cfg_import = json.load(open(config_file, "r", encoding="latin-1"))
        base_dir = Path(config_file).resolve().parent
        cfg_import["name"] = Path(config_file).stem
        if "logs_dir" not in cfg_import:
            cfg_import["logs_dir"] = "..\\logs"
        if "scripts_dir" not in cfg_import:
            cfg_import["scripts_dir"] = "C:\\GlobalCube\\Tasks\\scripts"
        if "target_dsn" in cfg_import:
            cfg_import["dest_dsn"] = cfg_import["target_dsn"]
            del cfg_import["target_dsn"]

        for folder in ["stage_dir", "batch_dir", "logs_dir", "scripts_dir"]:
            if cfg_import[folder].startswith(".."):
                cfg_import[folder] = str(base_dir.joinpath(cfg_import[folder]).resolve())
            os.makedirs(cfg_import[folder], exist_ok=True)
        for folder in ["source", "dest", "diff"]:
            os.makedirs(cfg_import["stage_dir"] + "\\" + folder, exist_ok=True)
        if ":" not in cfg_import["csv_file"]:
            cfg_import["csv_file"] = str((base_dir / cfg_import["csv_file"]).resolve())
        cfg_import["source_dsn"] = DsnConfig(**cfg_import["source_dsn"])
        cfg_import["dest_dsn"] = DsnConfig(**cfg_import["dest_dsn"])
        cfg = DbCreateConfig(**cfg_import)
        cfg.source_inspect = DatabaseInspect(cfg.source_dsn, source=True)
        cfg.dest_inspect = DatabaseInspect(cfg.dest_dsn, source=False)
        DbCreateConfig._cfg = cfg
        return cfg

    @staticmethod
    def get_instance():
        return DbCreateConfig._cfg

    def create_db_ini(self) -> None:
        with open(self.scripts_dir + "/../DB.ini", "w", encoding="cp850") as fwh:
            fwh.write(self.conn_ini)
            fwh.write("\n\n")
            fwh.write(self.source_dsn.conn_ini("SOURCE"))
            fwh.write("\n\n")
            fwh.write(self.dest_dsn.conn_ini("DEST"))
            fwh.write("\n")


@dataclass
class SourceTable:
    source: str
    client_db: str
    prefix: str

    @property
    def stage_csv(self) -> str:
        return ""

    @property
    def table_client(self) -> str:
        return ""

    @property
    def table_name(self) -> str:
        return ""

    @property
    def select_query(self) -> str:
        return ""


@dataclass
class DestTable:
    source: str
    dest: str
    dest_db: str
    filter_: str
    query: str
    iterative: str
    cols: str
    source_tables: list[SourceTable] = None
    dest_inspect: DatabaseInspect = None
    cfg: DbCreateConfig = None

    @property
    def table_batch_file(self) -> str:
        return f"{self.cfg.batch_dir}/{self.dest}.bat"

    @property
    def full_table_name(self) -> str:
        return f"[{self.dest_db}].[{self.cfg.dest_dsn.schema}].[{self.dest}]"

    @property
    def temp_table_name(self) -> str:
        return f"[{self.cfg.temp_db}].[temp].[{self.dest}]"

    @cached_property
    def columns_list(self) -> list[str]:
        res = self.dest_inspect.get_columns(self.dest)
        if "CLIENT_DB" in res:
            res.remove("CLIENT_DB")
            res.append("Client_DB")
        return res

    @cached_property
    def column_types(self) -> list[str]:
        return self.dest_inspect.get_columns_is_typeof_str(self.dest)

    @cached_property
    def primary_key(self) -> list[str]:
        return self.dest_inspect.get_pkey(self.dest, self.dest_db)

    @property
    def insert_query(self) -> str:
        return f"INSERT INTO {self.full_table_name} with (TABLOCK) SELECT * FROM {self.temp_table_name} T1"

    @property
    def delete_query(self) -> str:
        # pkey = self.primary_key
        if len(self.primary_key) == 0:
            return ""
        pkey_join_list = [f"T1.[{col}] = T2.[{col}]" for col in self.primary_key]
        pkey_join = " AND ".join(pkey_join_list)
        return f"DELETE T1 FROM {self.full_table_name} T1 INNER JOIN {self.temp_table_name} T2 ON {pkey_join}"


class SourceTable2(SourceTable):
    dest_table: DestTable
    cfg: DbCreateConfig

    _select_query: str = None
    source_inspect: DatabaseInspect = None
    info: str = ""

    @property
    def table_client(self) -> str:
        return f"{self.dest_table.dest}_{self.client_db}"

    @property
    def stage_csv(self) -> str:
        return f"{self.cfg.stage_dir}\\{self.table_client}.csv"

    @property
    def table_name(self) -> str:
        return self.source.format(self.prefix)

    @cached_property
    def source_columns(self) -> set[str]:
        return set(self.source_inspect.get_columns(self.table_name))

    @cached_property
    def select_query(self):
        f = io.StringIO()
        # print("Auf beiden Seiten: " + ";".join(intersect))
        diff1 = self.source_columns.difference(self.dest_table.columns_list)
        if len(diff1) > 0:
            f.write("rem Nur in Quelle: " + ";".join(diff1) + "\n")
        diff2 = set(self.dest_table.columns_list).difference(self.source_columns)
        if "Client_DB" not in diff2:
            f.write("echo Spalte 'Client_DB' fehlt!\n")
            return
        diff2.remove("Client_DB")
        if len(diff2) > 0:
            f.write("rem Nur in Ziel:   " + ";".join(diff2) + "\n")

        if not pd.isnull(self.dest_table.query):
            select_query = self.dest_table.query.format(self.prefix, self.cfg.filter[0], self.cfg.filter[1])
        elif "." in self.table_name or self.cfg.source_dsn.schema == "":
            if self.table_name[0] != "[":
                self.table_name = f"[{self.table_name}]"
            select_query = f"SELECT T1.* FROM {self.table_name} T1 "
        else:
            select_query = f"SELECT T1.* FROM [{self.cfg.source_dsn.schema}].[{self.table_name}] T1 "

        if not pd.isnull(self.dest_table.filter_):
            select_query += " WHERE " + self.dest_table.filter_.format("", self.cfg.filter[0], self.cfg.filter[1])
        elif "WHERE" not in select_query:
            select_query += " WHERE 1 = 1"

        if "timestamp" not in self.source_columns:
            print(self.dest_table.dest + " hat kein timestamp-Feld")
        self.info = f.getvalue()
        return select_query

    @property
    def select_query_with_columns(self) -> str:
        res = self.select_query.replace("T1.*", self.select_columns)
        if "timestamp" in self.source_columns:
            res += " ORDER BY T1.[timestamp] "
        return res

    @property
    def select_columns(self):
        intersect = self.source_columns.intersection(self.dest_table.columns_list)
        res = ""
        for col, is_char_type in zip(self.dest_table.columns_list, self.dest_table.column_types):
            if col in intersect:
                if False and is_char_type:  # vorerst deaktiviert
                    res += f"dbo.cln(T1.[{col}]), "
                else:
                    res += f"T1.[{col}], "
            elif col == "Client_DB":
                res += f"'{self.client_db}' as [Client_DB], "
            else:
                res += "'' as [" + col + "], "
        res = res[:-2]
        return res