# 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/.

"""
Templates provide a way of modifying the task definition of selected tasks.
They are added to 'try_task_config.json' and processed by the transforms.
"""


import json
import os
import pathlib
import subprocess
import sys
from abc import ABCMeta, abstractmethod, abstractproperty
from argparse import SUPPRESS, Action
from contextlib import contextmanager
from textwrap import dedent

import mozpack.path as mozpath
import requests
import six
from mozbuild.base import BuildEnvironmentNotFoundException, MozbuildObject
from mozversioncontrol import Repository
from taskgraph.util import taskcluster

from .tasks import resolve_tests_by_suite
from .util.ssh import get_ssh_user

here = pathlib.Path(__file__).parent
build = MozbuildObject.from_environment(cwd=str(here))


@contextmanager
def try_config_commit(vcs: Repository, commit_message: str):
    """Context manager that creates and removes a try config commit."""
    # Add the `try_task_config.json` file if it exists.
    try_task_config_path = pathlib.Path(build.topsrcdir) / "try_task_config.json"
    if try_task_config_path.exists():
        vcs.add_remove_files("try_task_config.json")

    try:
        # Create a try config commit.
        vcs.create_try_commit(commit_message)

        yield
    finally:
        # Revert the try config commit.
        vcs.remove_current_commit()


class ParameterConfig:
    __metaclass__ = ABCMeta

    def __init__(self):
        self.dests = set()

    def add_arguments(self, parser):
        for cli, kwargs in self.arguments:
            action = parser.add_argument(*cli, **kwargs)
            self.dests.add(action.dest)

    @abstractproperty
    def arguments(self):
        pass

    @abstractmethod
    def get_parameters(self, **kwargs) -> dict:
        pass

    def validate(self, **kwargs):
        pass


class TryConfig(ParameterConfig):
    @abstractmethod
    def try_config(self, **kwargs) -> dict:
        pass

    def get_parameters(self, **kwargs):
        result = self.try_config(**kwargs)
        if not result:
            return None
        return {"try_task_config": result}


class Artifact(TryConfig):
    arguments = [
        [
            ["--artifact"],
            {"action": "store_true", "help": "Force artifact builds where possible."},
        ],
        [
            ["--no-artifact"],
            {
                "action": "store_true",
                "help": "Disable artifact builds even if being used locally.",
            },
        ],
    ]

    def add_arguments(self, parser):
        group = parser.add_mutually_exclusive_group()
        return super().add_arguments(group)

    @classmethod
    def is_artifact_build(cls):
        try:
            return build.substs.get("MOZ_ARTIFACT_BUILDS", False)
        except BuildEnvironmentNotFoundException:
            return False

    def try_config(self, artifact, no_artifact, **kwargs):
        if artifact:
            return {"use-artifact-builds": True, "disable-pgo": True}

        if no_artifact:
            return

        if self.is_artifact_build():
            print("Artifact builds enabled, pass --no-artifact to disable")
            return {"use-artifact-builds": True, "disable-pgo": True}


class Pernosco(TryConfig):
    arguments = [
        [
            ["--pernosco"],
            {
                "action": "store_true",
                "default": None,
                "help": "Opt-in to analysis by the Pernosco debugging service.",
            },
        ],
        [
            ["--no-pernosco"],
            {
                "dest": "pernosco",
                "action": "store_false",
                "default": None,
                "help": "Opt-out of the Pernosco debugging service (if you are on the include list).",
            },
        ],
    ]

    def add_arguments(self, parser):
        group = parser.add_mutually_exclusive_group()
        return super().add_arguments(group)

    def try_config(self, pernosco, **kwargs):
        if pernosco is None:
            return

        if pernosco:
            try:
                # The Pernosco service currently requires a Mozilla e-mail address to
                # log in. Prevent people with non-Mozilla addresses from using this
                # flag so they don't end up consuming time and resources only to
                # realize they can't actually log in and see the reports.
                address = get_ssh_user()
                if not address.endswith("@mozilla.com"):
                    print(
                        dedent(
                            """\
                        Pernosco requires a Mozilla e-mail address to view its reports. Please
                        push to try with an @mozilla.com address to use --pernosco.

                            Current user: {}
                    """.format(
                                address
                            )
                        )
                    )
                    sys.exit(1)

            except (subprocess.CalledProcessError, IndexError):
                print("warning: failed to detect current user for 'hg.mozilla.org'")
                print("Pernosco requires a Mozilla e-mail address to view its reports.")
                while True:
                    answer = input(
                        "Do you have an @mozilla.com address? [Y/n]: "
                    ).lower()
                    if answer == "n":
                        sys.exit(1)
                    elif answer == "y":
                        break

        return {
            "env": {
                "PERNOSCO": str(int(pernosco)),
            }
        }

    def validate(self, **kwargs):
        try_config = kwargs["try_config_params"].get("try_task_config") or {}
        if try_config.get("use-artifact-builds"):
            print(
                "Pernosco does not support artifact builds at this time. "
                "Please try again with '--no-artifact'."
            )
            sys.exit(1)


class Path(TryConfig):
    arguments = [
        [
            ["paths"],
            {
                "nargs": "*",
                "default": [],
                "help": "Run tasks containing tests under the specified path(s).",
            },
        ],
    ]

    def try_config(self, paths, **kwargs):
        if not paths:
            return

        for p in paths:
            if not os.path.exists(p):
                print("error: '{}' is not a valid path.".format(p), file=sys.stderr)
                sys.exit(1)

        paths = [
            mozpath.relpath(mozpath.join(os.getcwd(), p), build.topsrcdir)
            for p in paths
        ]
        return {
            "env": {
                "MOZHARNESS_TEST_PATHS": six.ensure_text(
                    json.dumps(resolve_tests_by_suite(paths))
                ),
            }
        }


class Environment(TryConfig):
    arguments = [
        [
            ["--env"],
            {
                "action": "append",
                "default": None,
                "help": "Set an environment variable, of the form FOO=BAR. "
                "Can be passed in multiple times.",
            },
        ],
    ]

    def try_config(self, env, **kwargs):
        if not env:
            return
        return {
            "env": dict(e.split("=", 1) for e in env),
        }


class ExistingTasks(ParameterConfig):
    TREEHERDER_PUSH_ENDPOINT = (
        "https://treeherder.mozilla.org/api/project/try/push/?count=1&author={user}"
    )
    TREEHERDER_PUSH_URL = (
        "https://treeherder.mozilla.org/jobs?repo={branch}&revision={revision}"
    )

    arguments = [
        [
            ["-E", "--use-existing-tasks"],
            {
                "const": "last_try_push",
                "default": None,
                "nargs": "?",
                "help": """
                    Use existing tasks from a previous push. Without args this
                uses your most recent try push. You may also specify
                `rev=<revision>` where <revision> is the head revision of the
                try push or `task-id=<task id>` where <task id> is the Decision
                task id of the push. This last method even works for non-try
                branches.
                """,
            },
        ]
    ]

    def find_decision_task(self, use_existing_tasks):
        branch = "try"
        if use_existing_tasks == "last_try_push":
            # Use existing tasks from user's previous try push.
            user = get_ssh_user()
            url = self.TREEHERDER_PUSH_ENDPOINT.format(user=user)
            res = requests.get(url, headers={"User-Agent": "gecko-mach-try/1.0"})
            res.raise_for_status()
            data = res.json()
            if data["meta"]["count"] == 0:
                raise Exception(f"Could not find a try push for '{user}'!")
            revision = data["results"][0]["revision"]

        elif use_existing_tasks.startswith("rev="):
            revision = use_existing_tasks[len("rev=") :]

        else:
            raise Exception("Unable to parse '{use_existing_tasks}'!")

        url = self.TREEHERDER_PUSH_URL.format(branch=branch, revision=revision)
        print(f"Using existing tasks from: {url}")
        index_path = f"gecko.v2.{branch}.revision.{revision}.taskgraph.decision"
        return taskcluster.find_task_id(index_path)

    def get_parameters(self, use_existing_tasks, **kwargs):
        if not use_existing_tasks:
            return

        if use_existing_tasks.startswith("task-id="):
            tid = use_existing_tasks[len("task-id=") :]
        else:
            tid = self.find_decision_task(use_existing_tasks)

        label_to_task_id = taskcluster.get_artifact(tid, "public/label-to-taskid.json")
        return {"existing_tasks": label_to_task_id}


class RangeAction(Action):
    def __init__(self, min, max, *args, **kwargs):
        self.min = min
        self.max = max
        kwargs["metavar"] = "[{}-{}]".format(self.min, self.max)
        super().__init__(*args, **kwargs)

    def __call__(self, parser, namespace, values, option_string=None):
        name = option_string or self.dest
        if values < self.min:
            parser.error("{} can not be less than {}".format(name, self.min))
        if values > self.max:
            parser.error("{} can not be more than {}".format(name, self.max))
        setattr(namespace, self.dest, values)


class Rebuild(TryConfig):
    arguments = [
        [
            ["--rebuild"],
            {
                "action": RangeAction,
                "min": 2,
                "max": 20,
                "default": None,
                "type": int,
                "help": "Rebuild all selected tasks the specified number of times.",
            },
        ],
    ]

    def try_config(self, rebuild, **kwargs):
        if not rebuild:
            return

        if (
            not kwargs.get("new_test_config", False)
            and kwargs.get("full")
            and rebuild > 3
        ):
            print(
                "warning: limiting --rebuild to 3 when using --full. "
                "Use custom push actions to add more."
            )
            rebuild = 3

        return {
            "rebuild": rebuild,
        }


class Routes(TryConfig):
    arguments = [
        [
            ["--route"],
            {
                "action": "append",
                "dest": "routes",
                "help": (
                    "Additional route to add to the tasks "
                    "(note: these will not be added to the decision task)"
                ),
            },
        ],
    ]

    def try_config(self, routes, **kwargs):
        if routes:
            return {
                "routes": routes,
            }


class ChemspillPrio(TryConfig):
    arguments = [
        [
            ["--chemspill-prio"],
            {
                "action": "store_true",
                "help": "Run at a higher priority than most try jobs (chemspills only).",
            },
        ],
    ]

    def try_config(self, chemspill_prio, **kwargs):
        if chemspill_prio:
            return {"chemspill-prio": True}


class GeckoProfile(TryConfig):
    arguments = [
        [
            ["--gecko-profile"],
            {
                "dest": "profile",
                "action": "store_true",
                "default": False,
                "help": "Create and upload a gecko profile during talos/raptor tasks.",
            },
        ],
        [
            ["--gecko-profile-interval"],
            {
                "dest": "gecko_profile_interval",
                "type": float,
                "help": "How frequently to take samples (ms)",
            },
        ],
        [
            ["--gecko-profile-entries"],
            {
                "dest": "gecko_profile_entries",
                "type": int,
                "help": "How many samples to take with the profiler",
            },
        ],
        [
            ["--gecko-profile-features"],
            {
                "dest": "gecko_profile_features",
                "type": str,
                "default": None,
                "help": "Set the features enabled for the profiler.",
            },
        ],
        [
            ["--gecko-profile-threads"],
            {
                "dest": "gecko_profile_threads",
                "type": str,
                "help": "Comma-separated list of threads to sample.",
            },
        ],
        # For backwards compatibility
        [
            ["--talos-profile"],
            {
                "dest": "profile",
                "action": "store_true",
                "default": False,
                "help": SUPPRESS,
            },
        ],
        # This is added for consistency with the 'syntax' selector
        [
            ["--geckoProfile"],
            {
                "dest": "profile",
                "action": "store_true",
                "default": False,
                "help": SUPPRESS,
            },
        ],
    ]

    def try_config(
        self,
        profile,
        gecko_profile_interval,
        gecko_profile_entries,
        gecko_profile_features,
        gecko_profile_threads,
        **kwargs,
    ):
        if profile or not all(
            s is None for s in (gecko_profile_features, gecko_profile_threads)
        ):
            cfg = {
                "gecko-profile": True,
                "gecko-profile-interval": gecko_profile_interval,
                "gecko-profile-entries": gecko_profile_entries,
                "gecko-profile-features": gecko_profile_features,
                "gecko-profile-threads": gecko_profile_threads,
            }
            return {key: value for key, value in cfg.items() if value is not None}


class Browsertime(TryConfig):
    arguments = [
        [
            ["--browsertime"],
            {
                "action": "store_true",
                "help": "Use browsertime during Raptor tasks.",
            },
        ],
    ]

    def try_config(self, browsertime, **kwargs):
        if browsertime:
            return {
                "browsertime": True,
            }


class DisablePgo(TryConfig):
    arguments = [
        [
            ["--disable-pgo"],
            {
                "action": "store_true",
                "help": "Don't run PGO builds",
            },
        ],
    ]

    def try_config(self, disable_pgo, **kwargs):
        if disable_pgo:
            return {
                "disable-pgo": True,
            }


class NewConfig(TryConfig):
    arguments = [
        [
            ["--new-test-config"],
            {
                "action": "store_true",
                "help": "When a test fails (mochitest only) restart the browser and start from the next test",
            },
        ],
    ]

    def try_config(self, new_test_config, **kwargs):
        if new_test_config:
            return {
                "new-test-config": True,
            }


class WorkerOverrides(TryConfig):
    arguments = [
        [
            ["--worker-override"],
            {
                "action": "append",
                "dest": "worker_overrides",
                "help": (
                    "Override the worker pool used for a given taskgraph worker alias. "
                    "The argument should be `<alias>=<worker-pool>`. "
                    "Can be specified multiple times."
                ),
            },
        ],
        [
            ["--worker-suffix"],
            {
                "action": "append",
                "dest": "worker_suffixes",
                "help": (
                    "Override the worker pool used for a given taskgraph worker alias, "
                    "by appending a suffix to the work-pool. "
                    "The argument should be `<alias>=<suffix>`. "
                    "Can be specified multiple times."
                ),
            },
        ],
        [
            ["--worker-type"],
            {
                "action": "append",
                "dest": "worker_types",
                "default": [],
                "help": "Select tasks that only run on the specified worker.",
            },
        ],
    ]

    def try_config(self, worker_overrides, worker_suffixes, worker_types, **kwargs):
        from gecko_taskgraph.util.workertypes import get_worker_type
        from taskgraph.config import load_graph_config

        overrides = {}
        if worker_overrides:
            for override in worker_overrides:
                alias, worker_pool = override.split("=", 1)
                if alias in overrides:
                    print(
                        "Can't override worker alias {alias} more than once. "
                        "Already set to use {previous}, but also asked to use {new}.".format(
                            alias=alias, previous=overrides[alias], new=worker_pool
                        )
                    )
                    sys.exit(1)
                overrides[alias] = worker_pool

        if worker_suffixes:
            root = build.topsrcdir
            root = os.path.join(root, "taskcluster", "ci")
            graph_config = load_graph_config(root)
            for worker_suffix in worker_suffixes:
                alias, suffix = worker_suffix.split("=", 1)
                if alias in overrides:
                    print(
                        "Can't override worker alias {alias} more than once. "
                        "Already set to use {previous}, but also asked "
                        "to add suffix {suffix}.".format(
                            alias=alias, previous=overrides[alias], suffix=suffix
                        )
                    )
                    sys.exit(1)
                provisioner, worker_type = get_worker_type(
                    graph_config, worker_type=alias, parameters={"level": "1"}
                )
                overrides[alias] = "{provisioner}/{worker_type}{suffix}".format(
                    provisioner=provisioner, worker_type=worker_type, suffix=suffix
                )

        retVal = {}
        if worker_types:
            retVal["worker-types"] = list(overrides.keys()) + worker_types

        if overrides:
            retVal["worker-overrides"] = overrides
        return retVal


all_task_configs = {
    "artifact": Artifact,
    "browsertime": Browsertime,
    "chemspill-prio": ChemspillPrio,
    "disable-pgo": DisablePgo,
    "env": Environment,
    "existing-tasks": ExistingTasks,
    "gecko-profile": GeckoProfile,
    "new-test-config": NewConfig,
    "path": Path,
    "pernosco": Pernosco,
    "rebuild": Rebuild,
    "routes": Routes,
    "worker-overrides": WorkerOverrides,
}