# This Source Code Form is subject to the terms of the Mozilla Public
# License, v. 2.0. If a copy of the MPL was not distributed with this
# file, You can obtain one at http://mozilla.org/MPL/2.0/.
"""
Support for running toolchain-building jobs via dedicated scripts
"""

import os
from typing import Literal, Optional, Union

import taskgraph
from mozshellutil import quote as shell_quote
from taskgraph.util.schema import Schema, optionally_keyed_by, resolve_keyed_by

from gecko_taskgraph import GECKO
from gecko_taskgraph.transforms.job import configure_taskdesc_for_run, run_job_using
from gecko_taskgraph.transforms.job.common import (
    docker_worker_add_artifacts,
    generic_worker_add_artifacts,
)
from gecko_taskgraph.util.attributes import RELEASE_PROJECTS
from gecko_taskgraph.util.hash import hash_paths

CACHE_TYPE = "toolchains.v3"


class ToolchainRunSchema(Schema, kw_only=True):
    using: Literal["toolchain-script"]
    # The script (in taskcluster/scripts/misc) to run.
    # Python scripts are invoked with `mach python` so vendored libraries
    # are available.
    script: str
    # Arguments to pass to the script.
    arguments: Optional[list[str]] = None
    # If not false, tooltool downloads will be enabled via relengAPIProxy
    # for either just public files, or all files.  Not supported on Windows
    tooltool_downloads: Union[bool, Literal["public", "internal"]]
    # Sparse profile to give to checkout using `run-task`.  If given,
    # Defaults to "toolchain-build". The value is relative to
    # "sparse-profile-prefix", optionally defined below is the path,
    # defaulting to "build/sparse-profiles".
    # i.e. `build/sparse-profiles/toolchain-build`.
    # If `None`, instructs `run-task` to not use a sparse profile at all.
    sparse_profile: Optional[str]
    # The relative path to the sparse profile.
    sparse_profile_prefix: Optional[str] = None
    # Paths/patterns pointing to files that influence the outcome of a
    # toolchain build.
    resources: Optional[list[str]] = None
    # Path to the artifact produced by the toolchain job
    toolchain_artifact: str
    # An alias that can be used instead of the real toolchain job name in
    # fetch stanzas for jobs.
    toolchain_alias: Optional[
        optionally_keyed_by("project", Union[None, str, list[str]], use_msgspec=True)
    ] = None
    # Additional env variables to add to the worker when using this toolchain
    toolchain_env: Optional[dict[str, object]] = None
    # Whether the toolchain should be extracted after it is fetched
    # (default: True)
    toolchain_extract: Optional[bool] = None
    # Base work directory used to set up the task.
    workdir: Optional[str] = None

    def __post_init__(self):
        if self.tooltool_downloads is True:
            raise ValueError(
                "tooltool-downloads must be False, 'public', or 'internal'"
            )


def get_digest_data(config, run, taskdesc):
    files = list(run.pop("resources", []))
    # The script
    files.append("taskcluster/scripts/misc/{}".format(run["script"]))
    env = taskdesc["worker"].get("env", {})
    # Tooltool manifest if any is defined:
    tooltool_manifest = env.get("TOOLTOOL_MANIFEST")
    if tooltool_manifest:
        files.append(tooltool_manifest)

    # Store resources as an attribute for verification
    taskdesc.setdefault("attributes", {})["toolchain-resources"] = sorted(files)

    # Accumulate dependency hashes for index generation.
    data = [hash_paths(GECKO, files)]

    data.append(taskdesc["attributes"]["toolchain-artifact"])

    # If the task uses an in-tree docker image, we want it to influence
    # the index path as well. Ideally, the content of the docker image itself
    # should have an influence, but at the moment, we can't get that
    # information here. So use the docker image name as a proxy. Not a lot of
    # changes to docker images actually have an impact on the resulting
    # toolchain artifact, so we'll just rely on such important changes to be
    # accompanied with a docker image name change.
    image = taskdesc["worker"].get("docker-image", {}).get("in-tree")
    if image:
        data.append(image)

    # Likewise script arguments should influence the index.
    args = run.get("arguments")
    if args:
        data.extend(args)

    # Environment variables defined by the user (as opposed to added by transforms)
    for key, value in env.items():
        # Ignore the tooltool manifest because its content was already added above.
        if key == "TOOLTOOL_MANIFEST":
            continue
        data.append(f"##{key}={value}##")

    if taskdesc["attributes"].get("rebuild-on-release"):
        # Add whether this is a release branch or not
        data.append(str(config.params["project"] in RELEASE_PROJECTS))
    return data


def common_toolchain(config, job, taskdesc, is_docker):
    run = job["run"]

    worker = taskdesc["worker"] = job["worker"]
    worker["chain-of-trust"] = True

    if is_docker:
        # If the task doesn't have a docker-image, set a default
        worker.setdefault("docker-image", {"in-tree": "deb12-toolchain-build"})

    if job["worker"]["os"] == "windows":
        # There were no caches on generic-worker before bug 1519472, and they cause
        # all sorts of problems with Windows toolchain tasks, disable them until
        # tasks are ready.
        run["use-caches"] = False

    attributes = taskdesc.setdefault("attributes", {})
    attributes["toolchain-artifact"] = run["toolchain-artifact"]
    toolchain_artifact = attributes["toolchain-artifact"]
    if not toolchain_artifact.startswith("public/build/"):
        if "artifact_prefix" in attributes:
            raise Exception(
                "Toolchain {} has an artifact_prefix attribute. That is not"
                " allowed on toolchain tasks.".format(taskdesc["label"])
            )
        attributes["artifact_prefix"] = os.path.dirname(toolchain_artifact)

    # Note: this must be called before altering `env`.
    digest_data = get_digest_data(config, run, taskdesc)

    env = worker.setdefault("env", {})
    env.update({
        "MOZ_BUILD_DATE": config.params["moz_build_date"],
        "MOZ_SCM_LEVEL": config.params["level"],
        "TOOLCHAIN_ARTIFACT": run.pop("toolchain-artifact"),
    })

    if is_docker:
        # Toolchain checkouts don't live under {workdir}/checkouts
        workspace = "{workdir}/workspace/build".format(**run)
        env["GECKO_PATH"] = f"{workspace}/src"

    resolve_keyed_by(
        run,
        "toolchain-alias",
        item_name=taskdesc["label"],
        project=config.params["project"],
    )
    alias = run.pop("toolchain-alias", None)
    if alias:
        attributes["toolchain-alias"] = alias
    if "toolchain-env" in run:
        attributes["toolchain-env"] = run.pop("toolchain-env")
    if "toolchain-extract" in run:
        attributes["toolchain-extract"] = run.pop("toolchain-extract")

    # Allow the job to specify where artifacts come from, but add
    # public/build if it's not there already.
    artifacts = worker.setdefault("artifacts", [])
    if not artifacts:
        if is_docker:
            docker_worker_add_artifacts(config, job, taskdesc)
        else:
            generic_worker_add_artifacts(config, job, taskdesc)

    if job.get("attributes", {}).get("cached_task") is not False and not taskgraph.fast:
        name = taskdesc["label"].replace(f"{config.kind}-", "", 1)
        taskdesc["cache"] = {
            "type": CACHE_TYPE,
            "name": name,
            "digest-data": digest_data,
        }

    # Toolchains that are used for local development need to be built on a
    # level-3 branch to be installable via `mach bootstrap`.
    local_toolchain = taskdesc["attributes"].get("local-toolchain")
    if local_toolchain:
        if taskdesc.get("run-on-projects"):
            raise Exception(
                "Toolchain {} used for local developement must not have"
                " run-on-projects set".format(taskdesc["label"])
            )
        taskdesc["run-on-projects"] = ["integration", "release"]

    script = run.pop("script")
    arguments = run.pop("arguments", [])
    if local_toolchain and not attributes["toolchain-artifact"].startswith("public/"):
        # Local toolchains with private artifacts are expected to have a script that
        # fill a directory given as a final command line argument. That script, and the
        # arguments provided, are used by the build system bootstrap code, and for the
        # corresponding CI tasks, the command is wrapped with a script that creates an
        # artifact based on that filled directory.
        # We prefer automatic wrapping rather than manual wrapping in the yaml because
        # it makes the index independent of the wrapper script, which is irrelevant.
        # Also, an attribute is added for the bootstrap code to be able to easily parse
        # the command.
        attributes["toolchain-command"] = {
            "script": script,
            "arguments": list(arguments),
        }
        arguments.insert(0, script)
        script = "private_local_toolchain.sh"

    run["using"] = "run-task"
    if is_docker:
        gecko_path = "workspace/build/src"
    elif job["worker"]["os"] == "windows":
        gecko_path = "%GECKO_PATH%"
    else:
        gecko_path = "$GECKO_PATH"

    if is_docker:
        run["cwd"] = run["workdir"]
    run["command"] = [f"{gecko_path}/taskcluster/scripts/misc/{script}"] + arguments
    if not is_docker:
        # Don't quote the first item in the command because it purposely contains
        # an environment variable that is not meant to be quoted.
        if len(run["command"]) > 1:
            run["command"] = run["command"][0] + " " + shell_quote(*run["command"][1:])
        else:
            run["command"] = run["command"][0]

    configure_taskdesc_for_run(config, job, taskdesc, worker["implementation"])


toolchain_defaults = {
    "tooltool-downloads": False,
    "sparse-profile": "toolchain-build",
}


@run_job_using(
    "docker-worker",
    "toolchain-script",
    schema=ToolchainRunSchema,
    defaults=toolchain_defaults,
)
def docker_worker_toolchain(config, job, taskdesc):
    common_toolchain(config, job, taskdesc, is_docker=True)


@run_job_using(
    "generic-worker",
    "toolchain-script",
    schema=ToolchainRunSchema,
    defaults=toolchain_defaults,
)
def generic_worker_toolchain(config, job, taskdesc):
    common_toolchain(config, job, taskdesc, is_docker=False)