#!/usr/bin/env bash
# Ownership-Gate: kein Paket editiert Dateien eines anderen.
# Liest die Ownership-Tabelle aus STATE.md, mappt geaenderte Dateien (Branch vs.
# Basis) auf Pakete und FAILt bei Cross-Editing ueber >1 Paket-Grenze hinweg.
# Integration (Leader) ist ausgenommen: Branch main/master/integrate/*.
# Konvention: Verzeichnis-Pfade in der Tabelle mit Slash beenden (src/api/).
# Portabel gehalten (kein mapfile / keine assoziativen Arrays, laeuft auf bash 3.2).
set -uo pipefail

# Dormant solange das Template nicht initialisiert ist.
if grep -q '<id / datum>' STATE.md 2>/dev/null; then
  echo "[ownership] Template noch nicht initialisiert — uebersprungen."
  echo "GATE: PASS"; exit 0
fi

branch=$(git rev-parse --abbrev-ref HEAD 2>/dev/null || echo "")
case "$branch" in
  main|master|integrate/*)
    echo "[ownership] '$branch' ist Integrations-Branch — uebersprungen."
    echo "GATE: PASS"; exit 0 ;;
esac

# (pkg<TAB>prefix)-Zeilen aus der STATE.md-Ownership-Tabelle ziehen.
pairs=$(awk -F'|' '
  /Datei-Ownership/{f=1; next}
  f && /^[[:space:]]*$/{f=0}
  f && /^\|/{
    pkg=$2; paths=$3;
    gsub(/^[ \t]+|[ \t]+$/,"",pkg);
    if(pkg=="" || pkg=="Paket" || pkg ~ /---/ || pkg ~ /…/ || pkg ~ /^_/) next;
    n=split(paths, a, ",");
    for(i=1;i<=n;i++){ p=a[i]; gsub(/^[ \t]+|[ \t]+$/,"",p); gsub(/`/,"",p);
      if(p=="" || p ~ /…/ || p ~ /^_/) continue;
      print pkg "\t" p }
  }' STATE.md 2>/dev/null)

if [ -z "$pairs" ]; then
  echo "[ownership] keine befuellte Ownership-Tabelle in STATE.md — uebersprungen."
  echo "GATE: PASS"; exit 0
fi

base=$(git merge-base HEAD main 2>/dev/null || git rev-parse HEAD~1 2>/dev/null || true)
[ -n "$base" ] || { echo "[ownership] keine Diff-Basis — uebersprungen."; echo "GATE: PASS"; exit 0; }
changed=$(git diff --name-only "$base"...HEAD 2>/dev/null)
[ -n "$changed" ] || { echo "[ownership] keine Aenderungen — uebersprungen."; echo "GATE: PASS"; exit 0; }

hit=""; unowned=""
while IFS= read -r f; do
  [ -n "$f" ] || continue
  bestpre=""; bestpkg=""
  while IFS="	" read -r pkg pre; do
    [ -n "$pre" ] || continue
    case "$f" in
      "$pre"|"$pre"*)
        if [ "${#pre}" -gt "${#bestpre}" ]; then bestpre="$pre"; bestpkg="$pkg"; fi ;;
    esac
  done <<EOF
$pairs
EOF
  if [ -n "$bestpkg" ]; then
    hit="$hit$bestpkg
"
  else
    unowned="$unowned $f"
  fi
done <<EOF
$changed
EOF

distinct=$(printf '%s' "$hit" | sed '/^$/d' | sort -u)
n=$(printf '%s' "$distinct" | sed '/^$/d' | grep -c . || true)
echo "[ownership] Branch '$branch' beruehrt $n Paket(e): $(printf '%s ' $distinct)"
[ -n "$unowned" ] && echo "[ownership] Hinweis: ohne Owner in STATE.md:$unowned"

if [ "${n:-0}" -gt 1 ]; then
  echo "  - FAIL: Aenderungen ueber mehrere Ownership-Grenzen (Cross-Editing)."
  echo "    Worker editieren nur ihr Paket; Integration macht der Leader (Branch integrate/*)."
  echo "GATE: FAIL"; exit 1
fi
echo "GATE: PASS"