#!/usr/bin/env bash
set -euo pipefail

### CONFIG ###
DATE=$(date +%F)

# for deleting older files
DRY_RUN=false
KEEP_COUNT=1
#BASE_BACKUP_DIR="$HOME/backups/synapse"
BASE_BACKUP_DIR="/mnt/disk/backups/synapse"
BACKUP_DIR="$BASE_BACKUP_DIR/$DATE"

SYNAPSE_DIR="/opt/synapse"
SYNAPSE_DATA_DIR="/opt/synapse/synapse-data/_data"

POSTGRES_SERVICE="pg"
POSTGRES_DB="synapse"
POSTGRES_USER="matrix"

NGINX_DIR="/etc/nginx"
LETSENCRYPT_DIR="/etc/letsencrypt"


### Startup Info ###
echo "📦 Synapse backup started"
echo "📅 Date: $DATE"
echo "📁 Base Backups dir: $BASE_BACKUP_DIR"
echo "📁 Backup dir: $BACKUP_DIR"
echo

### remove old files ###
cd $BASE_BACKUP_DIR
echo "▶ cleanup older backup files ..."

cd $BASE_BACKUP_DIR

# Count the number of existing backups
TOTAL_BACKUPS=$(find . -name 'full-backup-*.tar.gz' | wc -l)
echo "Existing backup files ($TOTAL_BACKUPS) :"
# Find all full-backup-*.tar.gz files and list them
find . -name 'full-backup-*.tar.gz'| sort -k2,2 -t. -n -r | while IFS= read -r file; do
  echo "- $file"
done
echo 

# Find and list files that should be removed
echo "Files that will be deleted:"
files_to_delete=()
while IFS= read -r -d $'\0' dir; do
  files_to_delete+=("$dir")
  echo "- $dir"
done < <(find . -name 'full-backup-*.tar.gz' -newermt "$(( $KEEP_COUNT+1 )) days ago" ! -newermt "$KEEP_COUNT days ago" -print0)
echo

# Delete the files in dry-run mode or actually delete them
for file in "${files_to_delete[@]}"; do
  if [ "$DRY_RUN" = true ]; then
  echo "Will be deleted (Dry-Run): $file"
  else
    rm "$file"
    echo "Deleted $file"
  fi
done
echo

echo "Cleanup completed."

### PREP ###
mkdir -p "$BACKUP_DIR"

cd "$SYNAPSE_DIR"


### 1️⃣ Stop ONLY Synapse
echo "⏸ Stopping ONLY Synapse service (Postgres stays running)..."
docker compose stop synapse
echo

### 2️⃣ PostgreSQL backup
echo "🗄 Backing up PostgreSQL database..."
docker compose exec -T "$POSTGRES_SERVICE" \
  pg_dump -U "$POSTGRES_USER" -Fc "$POSTGRES_DB" \
  > "$BACKUP_DIR/synapse-postgres.dump"
echo "✅ PostgreSQL backup done"
echo

### 7️⃣ Start Synapse again
echo "▶ Starting Synapse service..."
docker compose up -d synapse
echo

### 3️⃣ Synapse data backup
echo "📁 Backing up Synapse data directory..."
tar -cJf "$BACKUP_DIR/synapse-data.tar.xz" \
  -C "$SYNAPSE_DATA_DIR" .
echo "✅ Synapse data backup done"
echo

### 4️⃣ docker compose config (ONLY docker-compose.yml)
echo "🐳 Backing up docker-compose.yml..."
cp "$SYNAPSE_DIR/docker-compose.yml" \
   "$BACKUP_DIR/docker-compose.yml"
echo "✅ docker compose config backed up"
echo

### 5️⃣ Nginx backup
echo "🌐 Backing up Nginx config..."
tar -czvf "$BACKUP_DIR/nginx.tar.gz" \
  "$NGINX_DIR"
echo "✅ Nginx backup done"
echo

## 6️⃣ Let's Encrypt backup
echo "🔐 Backing up Let's Encrypt certificates..."
sudo tar -czvf "$BACKUP_DIR/letsencrypt.tar.gz" \
  "$LETSENCRYPT_DIR"
echo "✅ Let's Encrypt backup done"
echo

### 8️⃣ Optional: Full combined archiveve (run with sudo)
echo "📦 Creating full backup archive..."
tar -czvf "$BASE_BACKUP_DIR/full-backup-$DATE.tar.gz" \
  -C "$BASE_BACKUP_DIR" "$DATE"
echo "✅ Full archive created"
echo

### Remove the backup dir after full archive

echo "📦 Removing the Backup directory: $DATE"
sudo rm -r $BACKUP_DIR
echo "Backup directory removed."
echo

echo "✅✅ Backup completed successfully"
echo