# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

"""Mercurial extension to run hooks on repositories."""

from __future__ import absolute_import

from mercurial import (
    configitems,
    registrar,
)
from mozhg.util import (
    identify_repo,
    timers,
)

testedwith = b"4.8 4.9 5.0 5.1 5.2 5.3 5.4 5.5"
minimumhgversion = b"4.8"
buglink = b"https://bugzilla.mozilla.org/enter_bug.cgi?product=Developer%20Services&component=Mercurial%3A%20hg.mozilla.org"

configtable = {}
configitem = registrar.configitem(configtable)

configitem(b"allowedroots", b".*", generic=True)
configitem(b"mozilla", b"check.*", generic=True)
configitem(b"mozilla", b"repo_root", default=configitems.dynamicdefault)
configitem(b"mozilla", b"treeherder_repo", default=None)
configitem(b"mozilla", b"check_bug_references_repos", default=None)
configitem(b"pushlog", b"autolanduser", default=b"bind-autoland@mozilla.com")
configitem(
    b"pushlog", b"landingworkeruser", default=b"lando_landing_worker@mozilla.com"
)
configitem(
    b"pushlog", b"landingworkeruser2", default=b"lando_landing_worker_2@mozilla.com"
)
configitem(
    b"pushlog", b"landingworkeruserdev", default=b"lando_landing_worker_dev@mozilla.com"
)


def get_check_classes(hook):
    # TODO come up with a mechanism for automatically discovering checks
    # so we don't have to enumerate them all.
    from mozhghooks.check import (
        advertise_upgrade,
        merge_day,
        prevent_cross_channel_messages,
        check_bug_references,
        prevent_conduit_arcconfig,
        prevent_repolocked_commits,
        prevent_subrepos,
        prevent_symlinks,
        prevent_sync_ipc_changes,
        prevent_webidl_changes,
        prevent_wptsync_changes,
        single_root,
        try_task_config_file,
    )

    # TODO check to hook mapping should also be automatically discovered.
    if hook == b"pretxnchangegroup":
        return (
            merge_day.MergeDayCheck,
            prevent_conduit_arcconfig.PreventConduitArcconfig,
            prevent_cross_channel_messages.XChannelMessageCheck,
            prevent_repolocked_commits.RepoLockedCheck,
            prevent_subrepos.PreventSubReposCheck,
            prevent_symlinks.PreventSymlinksCheck,
            prevent_sync_ipc_changes.SyncIPCCheck,
            prevent_webidl_changes.WebIDLCheck,
            prevent_wptsync_changes.WPTSyncCheck,
            single_root.SingleRootCheck,
            try_task_config_file.TryConfigCheck,
        )

    elif hook == b"changegroup":
        return (advertise_upgrade.AdvertiseUpgradeCheck,)

    elif hook == b"pretxnclose":
        return (check_bug_references.CheckBugReferencesCheck,)


def get_checks(ui, repo, source, classes):
    """Loads checks from classes.

    Returns a list of check instances that are active for the given repo.
    """

    # Never apply hooks at pull time or when re-applying from strips.
    if source in (b"pull", b"strip"):
        return []

    info = identify_repo(repo)

    # Don't apply to non-hosted repos.
    if not info[b"hosted"]:
        ui.write(b"(not running mozilla hooks on non-hosted repo)\n")
        return []

    checks = []

    for cls in classes:
        check = cls(ui, repo, info)
        name = check.name

        force_enable = False
        force_disable = False
        override = ui.config(b"mozilla", b"check.%s" % name)
        if override in (b"enable", b"true"):
            force_enable = True
        elif override in (b"disable", b"false"):
            force_disable = True

        enabled = check.relevant()
        if not isinstance(enabled, bool):
            raise Exception(b"relevant() must return a bool; got %s" % enabled)

        if enabled and force_disable:
            ui.warn(b"(%s check disabled per config override)\n" % name)
            continue
        elif not enabled and force_enable:
            ui.warn(b"(%s check enabled per config override)\n" % name)
            enabled = True

        if enabled:
            checks.append(check)

    return checks


def pretxnchangegroup(ui, repo, node, source=None, **kwargs):
    checks = get_checks(ui, repo, source, get_check_classes(b"pretxnchangegroup"))

    with timers(ui, b"mozhooks", b"mozhooks.pretxnchangegroup.") as times:
        for check in checks:
            with times.timeit(check.name):
                check.pre(node)

        for rev in repo.changelog.revs(repo[node].rev()):
            ctx = repo[rev]

            for check in checks:
                with times.timeit(check.name):
                    if not check.check(ctx):
                        return 1

        for check in checks:
            with times.timeit(check.name):
                if not check.post_check():
                    return 1

        return 0


def pretxnclose(ui, repo, node=None, source=None, txnname=None, **kwargs):
    # Only run hooks on a `push` transaction. `commit`, etc are not relevant
    if txnname != b"push":
        return 0

    checks = get_checks(ui, repo, source, get_check_classes(b"pretxnclose"))

    with timers(ui, b"mozhooks", b"mozhooks.pretxnclose.") as times:
        for check in checks:
            with times.timeit(check.name):
                check.pre(node)

        for rev in repo.changelog.revs(repo[node].rev()):
            ctx = repo[rev]

            for check in checks:
                with times.timeit(check.name):
                    if not check.check(ctx):
                        return 1

        for check in checks:
            with times.timeit(check.name):
                if not check.post_check():
                    return 1

        return 0


def changegroup(ui, repo, source=None, **kwargs):
    checks = get_checks(ui, repo, source, get_check_classes(b"changegroup"))

    with timers(ui, b"mozhooks", b"mozhooks.changegroup.") as times:
        for check in checks:
            with times.timeit(check.name):
                if not check.check(**kwargs):
                    return 1

        return 0


def reposetup(ui, repo):
    ui.setconfig(b"hooks", b"pretxnchangegroup.mozhooks", pretxnchangegroup)
    ui.setconfig(b"hooks", b"changegroup.mozhooks", changegroup)
    ui.setconfig(b"hooks", b"pretxnclose.mozhooks", pretxnclose)