#!/bin/bash

# MSP Monitor Dashboard - Database Backup Script
# Crea un backup de la base de datos PostgreSQL

set -e

# Configuracion
BACKUP_DIR="${BACKUP_DIR:-/backups}"
RETENTION_DAYS="${RETENTION_DAYS:-30}"
DATE=$(date +%Y%m%d_%H%M%S)
BACKUP_FILE="msp_monitor_${DATE}.sql.gz"

# Cargar variables de entorno
if [ -f .env ]; then
    export $(cat .env | grep -v '^#' | xargs)
fi

# Valores por defecto
DB_HOST="${DB_HOST:-localhost}"
DB_PORT="${DB_PORT:-5432}"
DB_USER="${POSTGRES_USER:-mspmonitor}"
DB_NAME="${POSTGRES_DB:-msp_monitor}"
DB_PASSWORD="${POSTGRES_PASSWORD:-changeme}"

echo "======================================"
echo "  MSP Monitor - Database Backup"
echo "======================================"
echo "Fecha: $(date)"
echo "Base de datos: $DB_NAME"
echo ""

# Crear directorio de backups si no existe
mkdir -p "$BACKUP_DIR"

# Crear backup
echo "Creando backup..."
export PGPASSWORD="$DB_PASSWORD"

pg_dump -h "$DB_HOST" -p "$DB_PORT" -U "$DB_USER" -d "$DB_NAME" \
    --no-owner --no-privileges --format=custom | gzip > "$BACKUP_DIR/$BACKUP_FILE"

unset PGPASSWORD

# Verificar que el backup se creo correctamente
if [ -f "$BACKUP_DIR/$BACKUP_FILE" ]; then
    SIZE=$(du -h "$BACKUP_DIR/$BACKUP_FILE" | cut -f1)
    echo "[✓] Backup creado: $BACKUP_DIR/$BACKUP_FILE ($SIZE)"
else
    echo "[✗] Error creando backup"
    exit 1
fi

# Eliminar backups antiguos
echo ""
echo "Limpiando backups antiguos (mas de $RETENTION_DAYS dias)..."
find "$BACKUP_DIR" -name "msp_monitor_*.sql.gz" -type f -mtime +$RETENTION_DAYS -delete
REMAINING=$(ls -1 "$BACKUP_DIR"/msp_monitor_*.sql.gz 2>/dev/null | wc -l)
echo "[✓] Backups restantes: $REMAINING"

# Opcional: Subir a S3 si esta configurado
if [ -n "$S3_BUCKET" ] && command -v aws &> /dev/null; then
    echo ""
    echo "Subiendo backup a S3..."
    aws s3 cp "$BACKUP_DIR/$BACKUP_FILE" "s3://$S3_BUCKET/backups/$BACKUP_FILE"
    echo "[✓] Backup subido a s3://$S3_BUCKET/backups/$BACKUP_FILE"
fi

echo ""
echo "======================================"
echo "  Backup completado"
echo "======================================"