#!/bin/bash
set -euo pipefail

# ====================================
# Forgejo restore script
# ====================================

# Where this script lives (Forgejo project root)
SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
cd "$SCRIPT_DIR"

BACKUP_DIR="$SCRIPT_DIR/backup"
TIMESTAMP="$(date +%Y-%m-%d_%H-%M-%S)"

usage() {
  echo "Usage: $0 <backup-file>"
  echo
  echo "  <backup-file> can be:"
  echo "    - Full path to a backup tar.gz"
  echo "    - Filename in the backup/ directory"
  echo "    - If omitted, the latest backup in backup/ is used (if available)"
  exit 1
}

# ------------------------------------
# 1) Pick backup file
# ------------------------------------
if [[ $# -ge 1 ]]; then
  INPUT_FILE="$1"
  # If it's not an absolute path and not already in backup/, assume it's in backup/
  if [[ "$INPUT_FILE" != /* && "$INPUT_FILE" != "$BACKUP_DIR/"* ]]; then
    BACKUP_FILE="$BACKUP_DIR/$INPUT_FILE"
  else
    BACKUP_FILE="$INPUT_FILE"
  fi
else
  # No argument → pick the latest backup in backup/
  echo "No backup file specified, selecting latest from $BACKUP_DIR..."
  BACKUP_FILE="$(ls -1t "$BACKUP_DIR"/forgejo-backup-*.tar.gz 2>/dev/null | head -n 1 || true)"
  if [[ -z "${BACKUP_FILE:-}" ]]; then
    echo "ERROR: No backups found in $BACKUP_DIR"
    usage
  fi
fi

if [[ ! -f "$BACKUP_FILE" ]]; then
  echo "ERROR: Backup file not found: $BACKUP_FILE"
  exit 1
fi

echo "=== Forgejo restore ==="
echo "Project dir : $SCRIPT_DIR"
echo "Backup dir  : $BACKUP_DIR"
echo "Backup file : $BACKUP_FILE"
echo

read -rp "!!! This will overwrite current Forgejo data. Continue? [y/N] " ANSWER
case "$ANSWER" in
  y|Y|yes|YES) ;;
  *) echo "Aborted."; exit 1 ;;
esac

# ------------------------------------
# 2) Stop Forgejo
# ------------------------------------
echo "[1/4] Stopping Forgejo containers (if running)..."
docker compose down || true

# ------------------------------------
# 3) Safety snapshot of current state
# ------------------------------------
SAFETY_BACKUP="$BACKUP_DIR/forgejo-pre-restore-${TIMESTAMP}.tar.gz"
echo "[2/4] Creating safety backup of CURRENT state -> $SAFETY_BACKUP"
tar -czf "$SAFETY_BACKUP" \
  forgejo \
  docker-compose.yml \
  .gitignore \
  README.md \
  .git 2>/dev/null || true

echo "[OK] Safety backup created."

# ------------------------------------
# 4) Restore from selected backup
# ------------------------------------
echo "[3/4] Removing current Forgejo data (moving to forgejo.old-$TIMESTAMP)..."

if [[ -d forgejo ]]; then
  mv forgejo "forgejo.old-$TIMESTAMP"
fi

# If config files exist, move them too (just in case)
for f in docker-compose.yml .gitignore README.md; do
  if [[ -f "$f" ]]; then
    mv "$f" "${f}.old-$TIMESTAMP"
  fi
done

echo "[4/4] Extracting backup archive..."
tar -xzf "$BACKUP_FILE" -C "$SCRIPT_DIR"

echo "=== Restore complete ==="
echo "Starting Forgejo containers..."
docker compose up -d

echo "Forgejo should now be running with data from:"
echo "  $BACKUP_FILE"
echo
echo "Previous state saved as:"
echo "  $SAFETY_BACKUP"
echo "  forgejo.old-$TIMESTAMP (and *.old-$TIMESTAMP for configs, if any)"