import pandas as pd
import pytest

from dashboard.libs.flux.flux import Flux, consume_flux
from dashboard.libs.repository.repository import AbstractRepository

FakeTable = pd.DataFrame
FakeSchema = dict[str, pd.DataFrame]
FakeSchemas = dict[str, FakeSchema]


class FakeRepository(AbstractRepository):
    def __init__(self, schemas: FakeSchemas):
        self._schemas = {}
        for schema_name, tables in schemas.items():
            schema = {}
            for table, df in tables.items():
                schema[table] = {
                    "df": df,
                    "metadata": {
                        "status": "new",
                        "qty_read": 0,
                        "qty_write": 0,
                    },
                }
            self._schemas[schema_name] = schema

    def schemas(self):
        """List schemas"""
        return list(self._schemas.keys())

    def tables(self, schema):
        """List table's name in schema"""
        return list(self._schemas[schema].keys())

    def infos(self, table: str, schema: str) -> dict[str, str]:
        """Get infos about the table"""
        return self._schemas[schema][table]["metadata"]

    def read(self, table, schema) -> pd.DataFrame:
        """Get content of the table"""
        self._schemas[schema][table]["metadata"]["qty_read"] += 1
        return self._schemas[schema][table]["df"]

    def write(self, content, table, schema) -> dict[str, str]:
        """Write content into the table"""
        try:
            self._schemas[schema][table]["df"] = content
        except KeyError:
            self._schemas[schema][table] = {
                "df": content,
                "metadata": {
                    "status": "new",
                    "qty_read": 0,
                    "qty_write": 0,
                },
            }
        self._schemas[schema][table]["metadata"]["status"] = "modified"
        self._schemas[schema][table]["metadata"]["qty_write"] += 1
        return self.infos(table, schema)

    def delete_table(self, table, schema):
        """Delete the table"""
        raise NotImplementedError


def test_fakerepository():
    fakerepository = FakeRepository(
        {
            "foo": {
                "table1": pd.DataFrame({"A": []}),
                "table2": pd.DataFrame({"B": []}),
            },
            "bar": {
                "table1": pd.DataFrame({"C": []}),
                "table2": pd.DataFrame({"D": []}),
            },
        }
    )
    assert fakerepository.schemas() == ["foo", "bar"]
    assert fakerepository.tables("foo") == ["table1", "table2"]
    assert fakerepository.infos("table1", "foo") == {
        "status": "new",
        "qty_read": 0,
        "qty_write": 0,
    }
    assert fakerepository.read("table1", "foo").equals(pd.DataFrame({"A": []}))
    assert fakerepository.infos("table1", "foo") == {
        "status": "new",
        "qty_read": 1,
        "qty_write": 0,
    }

    df = pd.DataFrame({"A": [1, 2]})
    assert fakerepository.write(df, "table1", "foo") == {
        "status": "modified",
        "qty_read": 1,
        "qty_write": 1,
    }


def test_consume_flux():
    source_repository = FakeRepository(
        {
            "source": {
                "table1": pd.DataFrame({"A": [1, 2, 3]}),
            },
        }
    )
    dest_repository = FakeRepository(
        {
            "destination": {},
        }
    )
    repositories = {
        "source": source_repository,
        "dest": dest_repository,
    }
    transformation = lambda dfs: {"dest": dfs[0] * 2}

    flux = Flux(
        sources=[{"repository": "source", "schema": "source", "table": "table1"}],
        destinations={
            "dest": {"repository": "dest", "schema": "destination", "table": "table1"}
        },
        transformation=transformation,
    )

    state = consume_flux(flux, repositories)
    assert state.statuses["dest"] == {'status': 'modified', 'qty_read': 0, 'qty_write': 1}
    assert dest_repository.read("table1", "destination").equals(pd.DataFrame({"A": [2, 4, 6]}))