# Copyright 2021 Google LLC

# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at

#     https://www.apache.org/licenses/LICENSE-2.0

# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.


import pathlib
import shutil
import subprocess
import tempfile

import changesummary

import describe

SCRIPTS_DIR = pathlib.Path(__file__).parent.resolve()
DISCOVERY_DOC_DIR = (
    SCRIPTS_DIR / ".." / "googleapiclient" / "discovery_cache" / "documents"
)
REFERENCE_DOC_DIR = SCRIPTS_DIR / ".." / "docs" / "dyn"
TEMP_DIR = SCRIPTS_DIR / "temp"


def main():
    # Clear discovery documents and reference documents directory
    shutil.rmtree(DISCOVERY_DOC_DIR, ignore_errors=True)
    shutil.rmtree(REFERENCE_DOC_DIR, ignore_errors=True)

    # Clear temporary directory
    shutil.rmtree(TEMP_DIR, ignore_errors=True)

    # Check out a fresh copy
    subprocess.call(["git", "checkout", DISCOVERY_DOC_DIR])
    subprocess.call(["git", "checkout", REFERENCE_DOC_DIR])

    # Snapshot current discovery artifacts to a temporary directory
    with tempfile.TemporaryDirectory() as current_discovery_doc_dir:
        shutil.copytree(
            DISCOVERY_DOC_DIR, current_discovery_doc_dir, dirs_exist_ok=True
        )

        # Download discovery artifacts and generate documentation
        describe.generate_all_api_documents(
            doc_destination_dir=REFERENCE_DOC_DIR,
            artifact_destination_dir=DISCOVERY_DOC_DIR,
        )

        # Get a list of files changed using `git diff`
        git_diff_output = subprocess.check_output(
            [
                "git",
                "diff",
                "origin/main",
                "--name-only",
                "--",
                DISCOVERY_DOC_DIR / "*.json",
                REFERENCE_DOC_DIR / "*.html",
                REFERENCE_DOC_DIR / "*.md",
            ],
            universal_newlines=True,
        )

        # Create lists of the changed files
        all_changed_files = [
            pathlib.Path(file_name).name for file_name in git_diff_output.split("\n")
        ]
        json_changed_files = [
            file for file in all_changed_files if file.endswith(".json")
        ]

        # Create temporary directory
        pathlib.Path(TEMP_DIR).mkdir()

        # Analyze the changes in discovery artifacts using the changesummary module
        changesummary.ChangeSummary(
            DISCOVERY_DOC_DIR, current_discovery_doc_dir, TEMP_DIR, json_changed_files
        ).detect_discovery_changes()

        # Write a list of the files changed to a file called `changed files` which will be used in the `createcommits.sh` script.
        with open(TEMP_DIR / "changed_files", "w") as f:
            f.writelines("\n".join(all_changed_files))


if __name__ == "__main__":
    main()