# Copyright (c) Microsoft Corporation.
# Licensed under the MIT License.

import os
from pathlib import Path
from typing import Literal

import fire

from mattergen.common.data.types import TargetProperty
from mattergen.common.utils.eval_utils import MatterGenCheckpointInfo
from mattergen.generator import CrystalGenerator


def main(
    output_path: str,
    model_path: str,
    batch_size: int = 64,
    num_batches: int = 1,
    config_overrides: list[str] | None = None,
    checkpoint_epoch: Literal["best", "last"] | int = "last",
    properties_to_condition_on: TargetProperty | None = None,
    sampling_config_path: str | None = None,
    sampling_config_name: str = "default",
    sampling_config_overrides: list[str] | None = None,
    record_trajectories: bool = True,
    diffusion_guidance_factor: float | None = None,
    strict_checkpoint_loading: bool = True,
    target_compositions: list[dict[str, int]] | None = None,
):
    """
    Evaluate diffusion model against molecular metrics.

    Args:
        model_path: Path to DiffusionLightningModule checkpoint directory.
        output_path: Path to output directory.
        config_overrides: Overrides for the model config, e.g., `model.num_layers=3 model.hidden_dim=128`.
        properties_to_condition_on: Property value to draw conditional sampling with respect to. When this value is an empty dictionary (default), unconditional samples are drawn.
        sampling_config_path: Path to the sampling config file. (default: None, in which case we use `DEFAULT_SAMPLING_CONFIG_PATH` from explorers.common.utils.utils.py)
        sampling_config_name: Name of the sampling config (corresponds to `{sampling_config_path}/{sampling_config_name}.yaml` on disk). (default: default)
        sampling_config_overrides: Overrides for the sampling config, e.g., `condition_loader_partial.batch_size=32`.
        load_epoch: Epoch to load from the checkpoint. If None, the best epoch is loaded. (default: None)
        record: Whether to record the trajectories of the generated structures. (default: True)
        strict_checkpoint_loading: Whether to raise an exception when not all parameters from the checkpoint can be matched to the model.
        target_compositions: List of dictionaries with target compositions to condition on. Each dictionary should have the form `{element: number_of_atoms}`. If None, the target compositions are not conditioned on.
           Only supported for models trained for crystal structure prediction (CSP) (default: None)

    NOTE: When specifying dictionary values via the CLI, make sure there is no whitespace between the key and value, e.g., `--properties_to_condition_on={key1:value1}`.
    """
    if not os.path.exists(output_path):
        os.makedirs(output_path)

    sampling_config_overrides = sampling_config_overrides or []
    config_overrides = config_overrides or []
    properties_to_condition_on = properties_to_condition_on or {}
    target_compositions = target_compositions or []

    checkpoint_info = MatterGenCheckpointInfo(
        model_path=Path(model_path).resolve(),
        load_epoch=checkpoint_epoch,
        config_overrides=config_overrides,
        strict_checkpoint_loading=strict_checkpoint_loading,
    )
    _sampling_config_path = Path(sampling_config_path) if sampling_config_path is not None else None
    generator = CrystalGenerator(
        checkpoint_info=checkpoint_info,
        properties_to_condition_on=properties_to_condition_on,
        batch_size=batch_size,
        num_batches=num_batches,
        sampling_config_name=sampling_config_name,
        sampling_config_path=_sampling_config_path,
        sampling_config_overrides=sampling_config_overrides,
        record_trajectories=record_trajectories,
        diffusion_guidance_factor=(
            diffusion_guidance_factor if diffusion_guidance_factor is not None else 0.0
        ),
        target_compositions_dict=target_compositions,
    )
    generator.generate(output_dir=Path(output_path))


if __name__ == "__main__":
    # use fire instead of argparse to allow for the specification of dictionary values via the CLI
    fire.Fire(main)