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"""Configuration of Cost Model Calibration."""

from __future__ import annotations
from dataclasses import dataclass
from enum import Enum
from typing import Callable, Sequence
from random_generator import RandomDistribution, DataType


@dataclass
class Config:
    """Main configuration class."""

    database: DatabaseConfig
    data_generator: DataGeneratorConfig
    abt_calibrator: AbtCalibratorConfig
    workload_execution: WorkloadExecutionConfig


@dataclass
class DatabaseConfig:
    """Database configuration."""

    connection_string: str
    database_name: str
    dump_path: str
    restore_from_dump: RestoreMode
    dump_on_exit: bool


class RestoreMode(Enum):
    """Restore database from dump mode."""

    # Never restore database from dump.
    NEVER = 0

    # Restore only new (non existing) database from dump
    ONLY_NEW = 1

    # Always restore database from dump
    ALWAYS = 2


@dataclass
class DataGeneratorConfig:
    """Data Generator configuration."""

    enabled: bool
    create_indexes: bool
    collection_templates: list[CollectionTemplate]
    collection_name_with_card: bool
    write_mode: WriteMode
    batch_size: int


@dataclass
class CollectionTemplate:
    """Collection template used to generate a collection with random data."""

    name: str
    fields: Sequence[FieldTemplate]
    compound_indexes: Sequence[Sequence[str]]
    cardinalities: Sequence[int]


@dataclass
class FieldTemplate:
    """Field template used to generate a collection with random data."""

    name: str
    data_type: DataType
    distribution: RandomDistribution
    indexed: bool


@dataclass
class AbtNodeCalibrationConfig:
    type: str
    filter_function: Callable[[any], any] = None
    variables_override: Sequence[str] = None


@dataclass
class AbtCalibratorConfig:
    """ABT Calibrator configuration."""

    enabled: bool
    # Share of data used for testing the model. Usually it should be around 0.1-0.3.
    test_size: float
    input_collection_name: str
    trace: bool
    nodes: Sequence[AbtNodeCalibrationConfig]


class WriteMode(Enum):
    """Write mode enum."""

    APPEND = 0
    REPLACE = 1


@dataclass
class WorkloadExecutionConfig:
    """Workload execution configuration."""

    enabled: bool
    output_collection_name: str
    write_mode: WriteMode
    warmup_runs: int
    runs: int


@dataclass
class BenchmarkConfig:
    """A/B performance testing config."""

    warmup_runs: int
    runs: int


@dataclass
class EntToEndTestingConfig:
    """End 2 End testing config."""

    database: DatabaseConfig
    data_generator: DataGeneratorConfig
    workload_execution: WorkloadExecutionConfig
    processor: End2EndProcessorConfig
    result_csv_filepath: str


@dataclass
class End2EndProcessorConfig:
    """Config of End 2 End tesing processor."""

    enabled: bool
    estimator: Callable[[str, int], float]
    input_collection_name: str