#!/usr/bin/env python3
#
# Copyright 2022 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.

"""Download and install renode release package."""

import argparse
import os
import re
import sys
import time
import tarfile
import urllib

from pathlib import Path

import wget


def download_artifact(url, artifact_name, out_dir):
    """Download the artifact from url."""
    if not os.path.isdir(out_dir):
        os.makedirs(out_dir)
    out_file = os.path.join(out_dir, artifact_name)
    download_url = os.path.join(url, artifact_name)
    num_retries = 3
    for i in range(num_retries + 1):
        try:
            wget.download(download_url, out=out_file)
            break
        except urllib.error.HTTPError as exception:
            if i == num_retries:
                raise
            print(f"{exception}\nDownload failed. Retrying...")
            time.sleep(5)
    return out_file


def strip_top_directory(tar):
    """Renode packages the release with a top directory. Need to strip it."""
    members = tar.getmembers()
    out_members = []
    for member in members[1:]:
        if member.path.startswith(members[0].name + "/"):
            member.path = os.path.join(
                *(member.name.split(os.path.sep)[1:]))
            out_members.append(member)

    tag = re.search("(.+?)_portable", members[0].name).group(1)
    return tag, out_members


def main():
    """Download and install renode release package."""
    pin_toolchains = os.getenv('PIN_TOOLCHAINS', '').lower().split(' ')
    if "renode" in pin_toolchains:
        print()
        print("****************************************************")
        print("*                                                  *")
        print("*  PIN_TOOLCHAINS includes renode! Skipping the    *")
        print("*  download of the latest Renode binaries.         *")
        print("*  PLEASE DON'T file bugs for Renode mis-behavior! *")
        print("*                                                  *")
        print("****************************************************")
        print()
        sys.exit(0)

    out_dir = os.getenv("OUT")
    if not out_dir:
        out_dir = "/tmp"

    parser = argparse.ArgumentParser(
        description="Download Renode from Antmicro releases")
    parser.add_argument(
        "--release_name", action="store", default="",
        help="Release to be downloaded. If not set, download the latest")
    parser.add_argument(
        "--release_url",
        action="store",
        default="https://dl.antmicro.com/projects/renode/builds/",
        help=("URL to check the IREE release."
              "(default: https://dl.antmicro.com/projects/renode/builds/)"))
    parser.add_argument(
        "--renode_dir", action="store", required=True,
        default="",
        help=("Renode installed directory")
    )

    args = parser.parse_args()

    with urllib.request.urlopen(args.release_url + '?C=M;O=D') as website:
        html_list = website.read().decode("utf-8")
    files = re.findall(r'href="(renode-.*git.*\.linux-portable\.tar\.gz)"',
                       html_list)

    release_found = False
    release_name = None
    if args.release_name:
        for file in files:
            if args.release_name in file:
                release_found = True
                release_name = re.search(
                    "(.+?).linux-portable.tar.gz", file).group(1)
                break
    else:
        # The latest nightly release is the symlink of the first entry.
        release_found = True
        release_name = re.search("(.+?).linux-portable.tar.gz",
                                 files[0]).group(1)

    if not release_found:
        print(f"!!!!!Renode can't be found with release {args.release_name}, "
              "please try a different release!!!!!")
        sys.exit(1)

    print(f"Release: {release_name}")
    commit_sha = re.search("git(.+?)$", release_name).group(1)

    renode_dir = Path(args.renode_dir)
    if not os.path.isdir(renode_dir):
        os.makedirs(renode_dir)
    tag_file = renode_dir / "tag"

    # Check the tag of the existing download.
    release_match = False
    built_from_src = False
    if os.path.isfile(tag_file):
        with open(tag_file, "r", encoding="utf-8") as file:
            for line in file:
                if "built_from_src" in line.replace("\n", ""):
                    built_from_src = True
                    break
                if commit_sha in line.replace("\n", ""):
                    release_match = True
                    break
    if built_from_src:
        print("Renode was built from the source. run `m renode_clean` if you "
              "want to download the nightly release.")
        sys.exit(0)
    if release_match:
        print("Renode is up-to-date")
        sys.exit(0)

    tmp_dir = Path(out_dir) / "tmp"
    artifact_name = release_name + ".linux-portable.tar.gz"
    tar_file = download_artifact(args.release_url, artifact_name, tmp_dir)

    # Extract the tarball
    with tarfile.open(tar_file) as tar:
        _, members = strip_top_directory(tar)
        tar.extractall(members=members, path=renode_dir)

    os.remove(tar_file)
    print("\nRenode is installed")

    # Add tag file for future checks
    with open(tag_file, "w", encoding="utf-8") as file:
        file.write(f"{release_name}\ncommit_sha: {commit_sha}\n")


if __name__ == "__main__":
    main()