# Copyright (C) 2022-present MongoDB, Inc.
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"""Cost Model Calibrator entry point."""

import os
import json
from data_generator import DataGenerator
from database_instance import DatabaseInstance
from config import Config
import abt_calibrator
import workload_execution

__all__ = []


def main():
    """Entry point function."""
    script_directory = os.path.abspath(os.path.dirname(__file__))
    os.chdir(script_directory)

    with open("config.json") as config_file:
        config = Config.create(json.load(config_file))

    # 1. Database Instance provides connectivity to a MongoDB instance, it loads data optionally
    # from the dump on creating and stores data optionally to the dump on closing.
    with DatabaseInstance(config.database) as database:

        # 2. Data generation (optional), generates random data and populates collections with it.
        generator = DataGenerator(database, config.data_generator)
        generator.populate_collections()
        collection_names = list(generator.list_collection_names())

        # 3. Collecting data for calibration (optional).
        # It runs the pipelines and stores explains to the database.
        pipelines = [
            [{'$match': {'f_5': 7}}],
            [{'$match': {'f_1': 5}}],
            [{'$match': {'f_7': 4}}],
            [{'$match': {'f_5': 7}}],
            [{'$match': {'f_1': 5}}],
            [{'$match': {'f_2': generator.gen_random_string()}}],
            [{'$match': {'f_5': generator.gen_random_string()}}],
        ]
        workload_execution.execute(database, config.workload_execution, collection_names, pipelines)

        # Calibration phase (optional).
        # Reads the explains stored on the previous step (this run and/or previous runs),
        # aparses the explains, nd calibrates the cost model for the ABT nodes.
        models = abt_calibrator.calibrate(config.abt_calibrator, database, ['IndexScan', 'Seek'])
        for abt, model in models.items():
            print(abt)
            print(model)


if __name__ == '__main__':
    main()