#!/usr/bin/env python3

"""Generate release notes from our commit log.

This uses the relnotes extension directives when they're available,

and falls back to our old pre-relnotes logic that used to live in the

release-tools repo.

"""

import argparse

import re

import subprocess

# Regenerate this list with

#   hg export 'grep("\.\. [a-z]+::")' | grep '^\.\.' | \

#     sed 's/.. //;s/::.*//' | sort -u

rnsections = ["api", "bc", "container", "feature", "fix", "note", "perf"]

rules = {

    # keep

    r"\(issue": 100,

    r"\(BC\)": 100,

    r"\(API\)": 100,

    # core commands, bump up

    r"(commit|files|log|pull|push|patch|status|tag|summary)(|s|es):": 20,

    r"(annotate|alias|branch|bookmark|clone|graft|import|verify).*:": 20,

    # extensions, bump up

    r"(mq|shelve|rebase):": 20,

    # newsy

    r": deprecate": 20,

    r"(option|feature|command|support)": 10,

    # bug-like?

    r"(fix|don't break|improve)": 7,

    # boring stuff, bump down

    r"^contrib": -5,

    r"debug": -5,

    r"help": -5,

    r"(doc|bundle2|obsolete|obsmarker|rpm|setup|debug\S+:)": -15,

    r"(check-code|check-commit|import-checker)": -20,

    # cleanups and refactoring

    r"(cleanup|whitespace|nesting|indent|spelling|comment)": -20,

    r"(typo|hint|note|style:|correct doc)": -20,

    r"_": -10,

    r"(argument|absolute_import|attribute|assignment|mutable)": -15,

    r"(unused|useless|unnecessary|duplicate|deprecated|scope|True|False)": -10,

    r"(redundant|pointless|confusing|uninitialized|meaningless|dead)": -10,

    r": (drop|remove|inherit|rename|simplify|naming|inline)": -10,

    r"(docstring|document .* method)": -20,

    r"(factor|extract|prepare|split|replace| import)": -20,

    r": add.*(function|method|implementation|test|example)": -10,

    r": (move|extract) .* (to|into|from)": -20,

    r": implement ": -5,

    r": use .* implementation": -20,

    r"\S\S\S+\.\S\S\S\S+": -5,

    r": use .* instead of": -20,

    r"__": -5,

    # dumb keywords

    r"\S+/\S+:": -10,

    r"\S+\.\S+:": -10,

    # drop

    r"^i18n-": -50,

    r"^i18n:.*(hint|comment)": -50,

    r"perf:": -50,

    r"check-code:": -50,

    r"Added.*for changeset": -50,

    r"tests?:": -50,

    r"test-": -50,

    r"add.* tests": -50,

    r"^_": -50,

}

cutoff = 10

commits = []

groupings = [

    (r"util|parsers|repo|ctx|context|revlog|filelog|alias|cmdutil", "core"),

    (r"revset|templater|ui|dirstate|hook|i18n|transaction|wire", "core"),

    (r"color|pager", "core"),

    (r"hgweb|paper|coal|gitweb", "hgweb"),

    (r"pull|push|revert|resolve|annotate|bookmark|branch|clone", "commands"),

    (r"commands|commit|config|files|graft|import|log|merge|patch", "commands"),

    (r"phases|status|summary|amend|tag|help|verify", "commands"),

    (r"rebase|mq|convert|eol|histedit|largefiles", "extensions"),

    (r"shelve|unshelve", "extensions"),

]

def main():

    ap = argparse.ArgumentParser()

    ap.add_argument(

        "startrev",

        metavar="REV",

        type=str,

        nargs=1,

        help=(

            "Starting revision for the release notes. This revision "

            "won't be included, but later revisions will."

        ),

    )

    ap.add_argument(

        "--stoprev",

        metavar="REV",

        type=str,

        default="@",

        nargs=1,

        help=(

            "Stop revision for release notes. This revision will be included,"

            " but no later revisions will. This revision needs to be "

            "a descendant of startrev."

        ),

    )

    args = ap.parse_args()

    fromext = subprocess.check_output(

        [

            "hg",

            "--config",

            "extensions.releasenotes=",

            "releasenotes",

            "-r",

            "%s::%s" % (args.startrev[0], args.stoprev[0]),

        ]

    ).decode("utf-8")

    # Find all release notes from un-relnotes-flagged commits.

    for entry in sorted(

        subprocess.check_output(

            [

                "hg",

                "log",

                "-r",

                r'%s::%s - merge() - grep("\n\.\. (%s)::")'

                % (args.startrev[0], args.stoprev[0], "|".join(rnsections)),

                "-T",

                r"{desc|firstline}\n",

            ]

        )

        .decode("utf-8")

        .splitlines()

    ):

        desc = entry.replace("`", "'")

        score = 0

        for rule, val in rules.items():

            if re.search(rule, desc):

                score += val

        desc = desc.replace("(issue", "(Bts:issue")

        if score >= cutoff:

            commits.append(desc)

    # Group unflagged notes.

    groups = {}

    bcs = []

    apis = []

    for d in commits:

        if "(BC)" in d:

            bcs.append(d)

        if "(API)" in d:

            apis.append(d)

        for rule, g in groupings:

            if re.match(rule, d):

                groups.setdefault(g, []).append(d)

                break

        else:

            groups.setdefault("unsorted", []).append(d)

    print(fromext)

    # print legacy release notes sections

    for g in sorted(groups):

        print("\n=== %s ===" % g)

        for d in sorted(groups[g]):

            print(" * %s" % d)

    print("\n=== BC ===\n")

    for d in sorted(bcs):

        print(" * %s" % d)

    print("\n=== API Changes ===\n")

    for d in sorted(apis):

        print(" * %s" % d)

if __name__ == "__main__":

    main()