import os
import argparse
from pathlib import Path
import scipy as sp

def print_matinfos(matrix: sp.sparse.coo_matrix) -> None:
    print(f"    - Size of the matrix: {matrix.shape}")
    print(f"    - Number of non-zero elements: {matrix.nnz}")
    print(f"    - Data type of the matrix: {matrix.dtype}")


def load_matrixmarket(path_input: Path) -> sp.sparse.coo_matrix:
    """
    Load a Matrix Market file and return it as scipy.sparse.coo_matrix.
    """
    print(f"    - Loaded Matrix Market file from: {path_input}")
    matrix = sp.io.mmread(path_input)
    print_matinfos(matrix)
    return matrix

def save_matrixmarket(matrix: sp.sparse.coo_matrix, path_output: Path) -> None:
    """
    Save a scipy.sparse.coo_matrix to a Matrix Market file.
    """
    print(f"    - Saving Matrix Market file to: {path_output}")
    sp.io.mmwrite(
        path_output, 
        matrix, 
    )
    print("    - Successfully saved Matrix Market file.")


if __name__ == "__main__":
    parser = argparse.ArgumentParser(description="Matrix Market utilities")
    parser.add_argument("command", choices=["mm2npz", "npz2mm"], help="Command to execute")
    parser.add_argument("input_file", help="Input file path")
    parser.add_argument("output_file", help="Output file path")

    args = parser.parse_args()

    print("args:", args)

    if args.command == "mm2npz":
        print("Converting Matrix Market to NPZ format:")
        matrix_coo = load_matrixmarket(args.input_file)
        input_matrix_name = os.path.splitext(os.path.basename(args.input_file))[0]
        output_matrix_name = Path.joinpath(
            Path(args.output_file), f"{input_matrix_name}.npz"
        )
        print(f"    - Saving to NPZ format: {output_matrix_name}")
        sp.sparse.save_npz(output_matrix_name, matrix_coo)
    elif args.command == "npz2mm":
        print("Converting NPZ to Matrix Market format:")
        matrix_coo = sp.sparse.load_npz(args.input_file).tocoo()
        print(f"    - Loaded NPZ file from: {args.input_file}")
        print_matinfos(matrix_coo)
        input_matrix_name = os.path.splitext(os.path.basename(args.input_file))[0]
        output_matrix_name = Path.joinpath(
            Path(args.output_file), f"{input_matrix_name}.mtx"
        )
        print(f"    - Saving to Matrix Market format: {output_matrix_name}")
        save_matrixmarket(matrix_coo, output_matrix_name)