#!/bin/sh
# commit-msg — refuse a message that names a locale.
#
# Every commit message on `main` is published verbatim on ftstore.app: the
# subject in the activity list, the body in the popup behind it. Naming the
# language a string was translated into says roughly where the person writing it
# lives, which is the one thing the whole "nothing about the author" rule in
# the project guide exists to prevent. See the section "Commit messages on `main` are
# PUBLIC" there for the reasoning.
#
# This hook exists because that rule was the only one in the guide with no way
# to check it, and it got broken twice in one session by someone who had read
# it. Prose that describes a rule is not the same as a thing that enforces one.
#
# Escape hatch: `git commit --no-verify`. It is here because a hook that cannot
# be overridden gets deleted rather than argued with, not because there is a
# good reason to name a locale.

msg_file="$1"
[ -f "$msg_file" ] || exit 0

# Strip comments and the diff `--verbose` appends, so neither can trip this.
body=$(sed -e '/^#/d' -e '/^diff --git /,$d' "$msg_file")

# Language names, whole word, case-insensitive. Locale *codes* are deliberately
# not matched: "de" and "en" appear inside ordinary words often enough that the
# false alarms would train everyone to pass --no-verify by reflex.
languages='German|Deutsch|English|Englisch|French|Français|Francais|Spanish|Español|Espanol|Italian|Italiano|Portuguese|Português|Portugues|Brazilian|Russian|Русский|Turkish|Türkçe|Turkce|Polish|Polski|Czech|Čeština|Cestina|Arabic|العربية|Persian|Farsi|فارسی|Thai|ไทย|Vietnamese|Việt|Indonesian|Bahasa|Chinese|中文|Mandarin|Simplified|Japanese|日本語|Korean|한국어'

hits=$(printf '%s\n' "$body" | grep -inE "\\b($languages)\\b" || true)

if [ -n "$hits" ]; then
	cat >&2 <<EOF

  This commit message names a language:

$(printf '%s\n' "$hits" | sed 's/^/      /')

  Commit messages on main are published word for word on ftstore.app, and a
  named locale points at a country. Say what landed, not who it is for:

      "translate the remaining UI strings"        not  "add german strings"
      "adds 4 strings in every locale it ships"   not  "in english and german"

  See CLAUDE.md, "Commit messages on \`main\` are PUBLIC".
  Override with: git commit --no-verify

EOF
	exit 1
fi

exit 0