# Copyright 2024 The Chromium Authors
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

"""Top-level presubmit for //third_party/rust

See https://www.chromium.org/developers/how-tos/depottools/presubmit-scripts
for more details about the presubmit API built into depot_tools.
"""

PRESUBMIT_VERSION = '2.0.0'

import re


def CheckForManualEditsOfGnrtAutogeneratedFiles(input_api, output_api):
    GNRT_INPUTS = [
        "tools/crates/gnrt/.*",
        "tools/crates/run_gnrt.py",
        "third_party/rust/chromium_crates_io/patches/.*",
        "third_party/rust/chromium_crates_io/Cargo.lock",
        "third_party/rust/chromium_crates_io/Cargo.toml",
        "third_party/rust/chromium_crates_io/BUILD.gn.hbs",
        "third_party/rust/chromium_crates_io/README.chromium.hbs",
        "third_party/rust/chromium_crates_io/gnrt_config.toml",
    ]
    GNRT_OUTPUTS = [
        "third_party/rust/chromium_crates_io/vendor/.*",
        "third_party/rust/[^/]*/v[0-9_]*/BUILD.gn",
        "third_party/rust/[^/]*/v[0-9_]*/README.chromium",
    ]
    input_regexes = [re.compile(r) for r in GNRT_INPUTS]
    output_regexes = [re.compile(r) for r in GNRT_OUTPUTS]
    is_input_path_predicate = lambda p: any(r.match(p) for r in input_regexes)
    is_output_path_predicate = lambda p: any(r.match(p) for r in output_regexes)

    affected_paths = [f.UnixLocalPath() for f in input_api.change.AffectedFiles()]
    affected_input_paths = filter(is_input_path_predicate, affected_paths)
    if not any(affected_input_paths):
        affected_output_paths = filter(is_output_path_predicate, affected_paths)

        error_msg_paths_count = 0
        error_msg_paths_snippet = ""
        for path in affected_output_paths:
            if error_msg_paths_count == 5:
                error_msg_paths_snippet += f"\n    ..."
                break
            else:
                error_msg_paths_snippet += f"\n    {path}"
                error_msg_paths_count += 1
        if error_msg_paths_count != 0:
            # TODO(lukasza): Ideally we would give a suggestion to run `gnrt`,
            # but `tools/crates/run_gnrt.py vendor` will only check the crate
            # version and won't redownload if the version matches expectations
            # (even if crate sources have been modified).
            return [output_api.PresubmitError(
                f"ERROR: The CL manually changes files auto-generated by `gnrt`",
                long_text=\
                    f"The CL modifies the following auto-generated file(s):" +
                    f"{error_msg_paths_snippet}\n" +
                    f"without modifying any generator inputs.\n" +
                    f"See `//docs/rust.md` for instructions for running `gnrt`"
            )]

    return []