#!/usr/bin/env python3
# Copyright lowRISC contributors.
# Licensed under the Apache License, Version 2.0, see LICENSE for details.
# SPDX-License-Identifier: Apache-2.0
"""autogen_testutils.py is a script for auto-generating a portion of the
`testutils` libraries from Mako templates.

`testutils` libraries are testing libraries that sit a layer above the DIFs
that aid in writing chip-level tests by enabling test developers to re-use
code that calls a specific collection of DIFs.

To render all testutil templates, run the script with:
$ util/autogen_testutils.py
"""

import glob
import logging
import shutil
import subprocess
import sys
from pathlib import Path

from mako.template import Template

from autogen_banner import get_autogen_banner
from make_new_dif.ip import Ip

# This file is $REPO_TOP/util/autogen_testutils.py, so it takes two parent()
# calls to get back to the top.
REPO_TOP = Path(__file__).resolve().parent.parent


def main():
    # Check clang-format is installed.
    assert (shutil.which("clang-format") and
            "ERROR: clang-format must be installed to format "
            " autogenerated code to pass OpenTitan CI checks.")

    # Define input/output directories.
    autogen_dif_directory = REPO_TOP / "sw/device/lib/dif/autogen"
    testutils_templates_dir = REPO_TOP / "util/autogen_testutils"
    autogen_testutils_dir = REPO_TOP / "sw/device/lib/testing/autogen"

    # Create list of IPs to generate shared testutils code for. This is all IPs
    # that have a DIF library, that the testutils functions can use.
    ips_with_difs = []
    for autogen_dif_filename in glob.iglob(str(autogen_dif_directory / "*.h")):
        # NOTE: the line below takes as input a file path
        # (/path/to/dif_uart_autogen.c) and returns the IP name in lower
        # case snake mode (i.e., uart).
        ip_name_snake = Path(autogen_dif_filename).stem[4:-8]
        # NOTE: ip.name_long_* not needed for auto-generated files which
        # are the only files (re-)generated in batch mode.
        ips_with_difs.append(Ip(ip_name_snake, "AUTOGEN"))
    ips_with_difs.sort(key=lambda ip: ip.name_snake)

    # Create output directories if needed.
    autogen_testutils_dir.mkdir(exist_ok=True)

    # Auto-generate testutils files.
    for suffix in [".h", ".c"]:
        for testutils_template_path_str in glob.iglob(
                str(testutils_templates_dir / f"*{suffix}.tpl")):
            testutils_template_path = Path(testutils_template_path_str)

            # Read in template, render it, and write it to the output file.
            testutils_template = Template(testutils_template_path.read_text())
            testutils = Path(autogen_testutils_dir /
                             testutils_template_path.stem)
            testutils.write_text(
                testutils_template.render(ips_with_difs=ips_with_difs,
                                          autogen_banner=get_autogen_banner(
                                              "util/autogen_testutils.py",
                                              comment="//")))

            # Format autogenerated file with clang-format.
            try:
                subprocess.check_call(["clang-format", "-i", testutils])
            except subprocess.CalledProcessError:
                logging.error(
                    f"failed to format {testutils} with clang-format.")
                sys.exit(1)

            print("testutils \"{}\" successfully written to {}.".format(
                suffix, str(testutils)))


if __name__ == "__main__":
    main()