#!/bin/sh
# aibysitter pre-commit hook: lints the staged content of rules files (not the working copy).
# Flags: AIBYSITTER_HOOK_ARGS, default --fail-on-error. CLI command: AIBYSITTER, default aibysitter.
# Skip once: git commit --no-verify. Docs: https://aibysitting.net/Hooks

AIBYSITTER=${AIBYSITTER:-aibysitter}
ARGS=${AIBYSITTER_HOOK_ARGS:---fail-on-error}

# Same paths as RulesFormats.FromFileName.
is_rules_file() {
    case "$1" in
        CLAUDE.md | */CLAUDE.md | AGENTS.md | */AGENTS.md | GEMINI.md | */GEMINI.md) return 0 ;;
        .cursorrules | .windsurfrules | .github/copilot-instructions.md) return 0 ;;
        .cursor/rules/*.mdc | */.cursor/rules/*.mdc) return 0 ;;
    esac
    return 1
}

if ! command -v "$AIBYSITTER" >/dev/null 2>&1; then
    echo "aibysitter pre-commit: '$AIBYSITTER' not found; rules files not linted. Install: https://aibysitting.net/Hooks" >&2
    exit 0
fi

git diff --cached --name-only --diff-filter=ACMR | {
    status=0
    while IFS= read -r path; do
        is_rules_file "$path" || continue
        # shellcheck disable=SC2086
        if ! git show ":$path" | "$AIBYSITTER" lint - --stdin-path "$path" $ARGS; then
            status=1
        fi
    done
    if [ "$status" -ne 0 ]; then
        echo "aibysitter pre-commit: commit blocked. Fix the findings above, or skip once with git commit --no-verify." >&2
    fi
    exit "$status"
}