# -*- coding: utf-8 -*-

import argparse
import errno
import json
import logging
import os
import shutil
import subprocess
import sys
import tarfile
import tempfile
import time
import warnings
from datetime import timedelta
from pathlib import Path

import magic
import requests
import tenacity
import zstandard

from firefox_code_coverage import taskcluster

FINISHED_STATUSES = ["completed", "failed", "exception"]
ALL_STATUSES = FINISHED_STATUSES + ["unscheduled", "pending", "running"]
STATUS_VALUE = {"exception": 1, "failed": 2, "completed": 3}

GRCOV_INDEX = "gecko.cache.level-1.toolchains.v3.linux64-grcov.latest"
GRCOV_ARTIFACT = "public/build/grcov.tar.zst"

logger = logging.getLogger(__name__)


def is_taskcluster_loaner():
    return "TASKCLUSTER_INTERACTIVE" in os.environ


def get_task(branch, revision):
    index = taskcluster.get_service("index")
    task = index.findTask(f"gecko.v2.{branch}.revision.{revision}.taskgraph.decision")
    return task["taskId"]


def get_last_task():
    resp = requests.get(
        "https://api.coverage.moz.tools/v2/latest?repository=mozilla-central"
    )
    resp.raise_for_status()
    data = resp.json()
    revision = data[0]["revision"]
    return get_task("mozilla-central", revision)


def get_task_details(task_id):
    queue = taskcluster.get_service("queue")
    return queue.task(task_id)


def get_task_artifacts(task_id):
    queue = taskcluster.get_service("queue")
    response = queue.listLatestArtifacts(task_id)
    return response["artifacts"]


def get_tasks_in_group(group_id):
    tasks = []

    def _save_tasks(response):
        tasks.extend(response["tasks"])

    queue = taskcluster.get_service("queue")
    queue.listTaskGroup(group_id, paginationHandler=_save_tasks)

    return tasks


@tenacity.retry(
    stop=tenacity.stop_after_attempt(5),
    wait=tenacity.wait_exponential(multiplier=1, min=16, max=64),
    reraise=True,
)
def download_binary(url, path):
    """Download a binary file from an url"""

    try:
        artifact = requests.get(url, stream=True)
        artifact.raise_for_status()

        with open(path, "wb") as f:
            for chunk in artifact.iter_content(chunk_size=8192):
                f.write(chunk)

    except Exception:
        try:
            os.remove(path)
        except OSError:
            pass

        raise


def download_artifact(task_id, artifact, artifacts_path):
    fname = os.path.join(
        artifacts_path, task_id + "_" + os.path.basename(artifact["name"])
    )

    # As recommended by Taskcluster doc, use requests to download
    # from the artifact public url instead of relying on the client method
    queue = taskcluster.get_service("queue")
    url = queue.buildUrl("getLatestArtifact", task_id, artifact["name"])

    if not os.path.exists(fname):
        download_binary(url, fname)

    return fname


def get_chunk(task_name):
    # Some tests are run on build machines, we define placeholder chunks for those.
    if task_name.startswith("build-signing-"):
        return "build-signing"
    elif task_name.startswith("build-"):
        return "build"

    task_name = task_name[task_name.find("/") + 1 :]
    return "-".join(
        p for p in task_name.split("-") if p not in ("opt", "debug", "e10s", "1proc")
    )


def get_suite(task_name):
    return "-".join(p for p in get_chunk(task_name).split("-") if not p.isdigit())


def get_platform(task_name):
    if "linux" in task_name:
        return "linux"
    elif "win" in task_name:
        return "windows"
    elif "macosx" in task_name:
        return "macos"
    # Assume source-test tasks without the OS name in the label are on Linux.
    elif "source-test" in task_name:
        return "linux"
    else:
        raise Exception(f"Unknown platform for {task_name}")


def get_task_status(task_id):
    queue = taskcluster.get_service("queue")
    status = queue.status(task_id)
    return status["status"]["state"]


def download_coverage_artifacts(
    decision_task_id,
    suites,
    platforms,
    artifacts_path,
    suites_to_ignore=["talos", "awsy"],
):
    try:
        os.mkdir(artifacts_path)
    except OSError as e:
        if e.errno != errno.EEXIST:
            raise e

    task_data = get_task_details(decision_task_id)

    # Returns True if the task is a test-related coverage task (build tasks are included).
    def _is_test_task(t):
        return "ccov" in t["task"]["metadata"]["name"].split("/")[0].split("-")

    # Returns True if the task is part of one of the suites chosen by the user.
    def _is_in_suites_task(t):
        suite_name = get_suite(t["task"]["metadata"]["name"])
        return (
            suites is None or suite_name in suites
        ) and suite_name not in suites_to_ignore

    def _is_in_platforms_task(t):
        platform = get_platform(t["task"]["metadata"]["name"])
        return platforms is None or platform in platforms

    test_tasks = [
        t
        for t in get_tasks_in_group(task_data["taskGroupId"])
        if _is_test_task(t) and _is_in_suites_task(t) and _is_in_platforms_task(t)
    ]

    if suites is not None:
        for suite in suites:
            if not any(suite in t["task"]["metadata"]["name"] for t in test_tasks):
                warnings.warn("Suite %s not found" % suite)

    download_tasks = {}

    for test_task in test_tasks:
        status = test_task["status"]["state"]
        assert status in ALL_STATUSES, "State '{}' not recognized".format(status)

        while status not in FINISHED_STATUSES:
            sys.stdout.write(
                "\rWaiting for task {} to finish...".format(
                    test_task["status"]["taskId"]
                )
            )
            sys.stdout.flush()
            time.sleep(60)
            status = get_task_status(test_task["status"]["taskId"])
            # Update the task status, as we will use it to compare statuses later.
            test_task["status"]["state"] = status
            assert status in ALL_STATUSES

        chunk_name = get_chunk(test_task["task"]["metadata"]["name"])
        platform_name = get_platform(test_task["task"]["metadata"]["name"])

        if (chunk_name, platform_name) not in download_tasks:
            download_tasks[(chunk_name, platform_name)] = test_task
        else:
            prev_task = download_tasks[(chunk_name, platform_name)]
            if STATUS_VALUE[status] > STATUS_VALUE[prev_task["status"]["state"]]:
                download_tasks[(chunk_name, platform_name)] = test_task

    artifact_paths = []
    for i, test_task in enumerate(download_tasks.values()):
        sys.stdout.write(
            "\rDownloading artifacts from {}/{} test task...".format(i, len(test_tasks))
        )
        sys.stdout.flush()
        artifacts = get_task_artifacts(test_task["status"]["taskId"])
        for artifact in artifacts:
            if any(
                a in artifact["name"]
                for a in ["code-coverage-grcov.zip", "code-coverage-jsvm.zip"]
            ):
                artifact_paths.append(
                    download_artifact(
                        test_task["status"]["taskId"], artifact, artifacts_path
                    )
                )
    print("")
    return artifact_paths


def generate_report(grcov_path, output_format, src_dir, output_path, artifact_paths):
    mod_env = os.environ.copy()
    if is_taskcluster_loaner():
        one_click_loaner_gcc = "/home/worker/workspace/build/src/gcc/bin"
        i = 0
        while (
            not os.path.isdir(one_click_loaner_gcc)
            or len(os.listdir(one_click_loaner_gcc)) == 0
        ):
            print("Waiting one-click loaner to be ready... " + str(i))
            i += 1
            time.sleep(60)
        mod_env["PATH"] = one_click_loaner_gcc + ":" + mod_env["PATH"]
    cmd = [
        grcov_path,
        "-t",
        output_format,
        "-o",
        output_path,
    ]
    if src_dir is not None:
        cmd += ["-s", src_dir, "--ignore-not-existing"]
    if output_format in ["coveralls", "coveralls+"]:
        cmd += ["--token", "UNUSED", "--commit-sha", "UNUSED"]
    cmd.extend(artifact_paths)
    proc = subprocess.Popen(cmd, stderr=subprocess.PIPE, env=mod_env)
    i = 0
    while proc.poll() is None:
        if i % 60 == 0:
            sys.stdout.write("\rRunning grcov... {} seconds".format(i))
            sys.stdout.flush()
        i += 1
        time.sleep(1)
    print("")

    if proc.poll() != 0:
        raise Exception("Error while running grcov: {}\n".format(proc.stderr.read()))


def download_grcov():
    local_path = os.path.join(os.getcwd(), "grcov")
    local_version = os.path.join(os.getcwd(), "grcov_ver")

    dest = tempfile.mkdtemp(suffix="grcov")
    archive = os.path.join(dest, "grcov.tar.zst")
    index = taskcluster.get_service("index")
    url = index.buildUrl("findArtifactFromTask", GRCOV_INDEX, GRCOV_ARTIFACT)
    download_binary(url, archive)

    # Extract archive in temp
    dctx = zstandard.ZstdDecompressor()
    with open(archive, "rb") as f:
        with dctx.stream_reader(f) as reader:
            with tarfile.open(mode="r|", fileobj=reader) as tar:
                tar.extractall(dest)
    os.remove(archive)

    # Get version from grcov binary
    grcov = os.path.join(dest, "grcov", "grcov")
    assert os.path.exists(grcov), "Missing grcov binary"
    assert os.path.isfile(grcov), "grcov should be a file"
    version = subprocess.check_output([grcov, "--version"]).decode("utf-8")

    # Compare version with currently available
    if os.path.exists(local_path) and os.path.exists(local_version):
        with open(local_version, "r") as f:
            installed_ver = f.read()

        if installed_ver == version:
            return local_path

    # Promote downloaded version to installed one
    shutil.move(grcov, local_path)
    shutil.rmtree(dest)
    with open(local_version, "w") as f:
        f.write(version)

    return local_path


def upload_html_report(
    report_dir, base_artifact="public/report", ttl=timedelta(days=10)
):
    assert os.path.isdir(report_dir), "Not a directory {}".format(report_dir)
    report_dir = os.path.realpath(report_dir)
    assert not base_artifact.endswith("/"), "No trailing / in base_artifact"

    # Use Taskcluster proxy when available
    taskcluster.auth()

    for path in Path(report_dir).rglob("*"):
        filename = str(path.relative_to(report_dir))
        content_type = magic.from_file(str(path), mime=True)
        logger.debug("Uploading {} as {}".format(filename, content_type))

        taskcluster.upload_artifact(
            "{}/{}".format(base_artifact, filename), path.read_text(), content_type, ttl
        )


def main():
    parser = argparse.ArgumentParser()

    if is_taskcluster_loaner():
        nargs = "?"
        default_src_dir = "/home/worker/workspace/build/src/"
        default_branch = os.environ["MH_BRANCH"]
        default_commit = os.environ["GECKO_HEAD_REV"]
    else:
        nargs = None
        default_src_dir = None
        default_branch = None
        default_commit = None

    parser.add_argument(
        "src_dir",
        action="store",
        nargs=nargs,
        default=default_src_dir,
        help="Path to the source directory",
    )
    parser.add_argument(
        "branch",
        action="store",
        nargs="?",
        default=default_branch,
        help="Branch on which jobs ran",
    )
    parser.add_argument(
        "commit",
        action="store",
        nargs="?",
        default=default_commit,
        help="Commit hash for push",
    )
    parser.add_argument("--grcov", action="store", nargs="?", help="Path to grcov")
    parser.add_argument(
        "--with-artifacts",
        action="store",
        nargs="?",
        default="ccov-artifacts",
        help="Path to already downloaded coverage files",
    )
    parser.add_argument(
        "--platform",
        action="store",
        nargs="+",
        help='List of platforms to include (by default they are all included). E.g. "linux", "windows", etc.',
    )
    parser.add_argument(
        "--suite",
        action="store",
        nargs="+",
        help='List of test suites to include (by default they are all included). E.g. "mochitest", "mochitest-chrome", "gtest", etc.',
    )
    parser.add_argument(
        "--ignore",
        action="store",
        nargs="+",
        help='List of test suites to ignore (by default "talos" and "awsy"). E.g. "mochitest", "mochitest-chrome", "gtest", etc.',
    )
    parser.add_argument(
        "--stats",
        action="store_true",
        help="Only generate high-level stats, not a full HTML report",
    )
    parser.add_argument(
        "-o",
        "--output-dir",
        help="The output directory for generated report",
        default=os.path.join(os.getcwd(), "ccov-report"),
    )
    args = parser.parse_args()

    os.makedirs(args.output_dir, exist_ok=True)

    if (args.branch is None) != (args.commit is None):
        parser.print_help()
        return

    if args.branch and args.commit:
        task_id = get_task(args.branch, args.commit)
    else:
        task_id = get_last_task()

    if args.ignore is None:
        artifact_paths = download_coverage_artifacts(
            task_id, args.suite, args.platform, args.with_artifacts
        )
    else:
        artifact_paths = download_coverage_artifacts(
            task_id, args.suite, args.platform, args.with_artifacts, args.ignore
        )

    if args.grcov:
        grcov_path = args.grcov
    else:
        grcov_path = download_grcov()

    if args.stats:
        output = os.path.join(args.output_dir, "output.json")
        generate_report(grcov_path, "coveralls", args.src_dir, output, artifact_paths)

        with open(output, "r") as f:
            report = json.load(f)

        total_lines = 0
        total_lines_covered = 0
        for sf in report["source_files"]:
            for c in sf["coverage"]:
                if c is None:
                    continue

                total_lines += 1
                if c > 0:
                    total_lines_covered += 1

        print("Coverable lines: {}".format(total_lines))
        print("Covered lines: {}".format(total_lines_covered))
        print(
            "Coverage percentage: {}".format(
                float(total_lines_covered) / float(total_lines)
            )
        )
    else:
        generate_report(
            grcov_path, "html", args.src_dir, args.output_dir, artifact_paths
        )

        if is_taskcluster_loaner():
            upload_html_report(args.output_dir)


if __name__ == "__main__":
    main()