#!/bin/bash
# Source-tree hygiene guard.
#
# Blocks two failure modes that an AI coding session previously introduced in
# src/wallet/ (the lite-wallet "_plan"/"_batch" churn): pathologically long
# filenames (which also break the Windows MAX_PATH 260-char limit during the
# cross-build) and the runaway "receipt/custody/handoff/stewardship" naming
# explosion where each session wrapped the previous artifact in one more layer.
#
# Usage:
#   scripts/check-source-hygiene.sh            # check working-tree src/
#   scripts/check-source-hygiene.sh --staged   # check staged files (pre-commit)
#
# Install as a git pre-commit hook:
#   ln -sf ../../scripts/check-source-hygiene.sh .git/hooks/pre-commit
#   # (the hook invokes it with --staged automatically when named pre-commit)

set -euo pipefail

MAX_LEN=80
# Naming-explosion tokens. Two or more chained in one basename is the smell.
CHURN_RE='receipt|custody|handoff|stewardship|promotion_activation|acceptance_confirmation|archive_handoff|post_closure'

mode="${1:-}"
if [[ "$mode" == "--staged" || "$(basename "$0")" == "pre-commit" ]]; then
    mapfile -t files < <(git diff --cached --name-only --diff-filter=AR | grep -E '\.(cpp|h|hpp|cc)$' || true)
else
    mapfile -t files < <(git ls-files 'src/**/*.cpp' 'src/**/*.h' 2>/dev/null; \
                         find src -type f \( -name '*.cpp' -o -name '*.h' \) 2>/dev/null)
    # de-dup
    mapfile -t files < <(printf '%s\n' "${files[@]}" | sort -u)
fi

fail=0
for f in "${files[@]}"; do
    [[ -z "$f" ]] && continue
    base="$(basename "$f")"
    len=${#base}
    if (( len > MAX_LEN )); then
        echo "✗ filename too long ($len > $MAX_LEN chars): $f" >&2
        fail=1
    fi
    # count distinct churn tokens in the basename ( || true: grep exits 1 on no match)
    n=$(printf '%s' "$base" | grep -oE "$CHURN_RE" | sort -u | wc -l || true)
    if (( n >= 2 )); then
        echo "✗ runaway naming pattern ($n churn tokens) — refactor in place, don't add a layer: $f" >&2
        fail=1
    fi
done

if (( fail )); then
    echo "" >&2
    echo "Source hygiene check failed. See docs in scripts/check-source-hygiene.sh." >&2
    exit 1
fi
echo "source hygiene OK (${#files[@]} files checked)"