#!/bin/bash
# ============================================================================
# Gitea Backup Script
# ============================================================================
# Backs up PostgreSQL database and Gitea data directory to AWS S3
#
# Usage: ./backup.sh
# ============================================================================

set -e

# ============================================================================
# Configuration
# ============================================================================
readonly TIMESTAMP=$(date +%Y%m%d_%H%M%S)
readonly BACKUP_DIR="/tmp/gitea-backup-${TIMESTAMP}"
readonly S3_BUCKET="qvest-task-backups"
readonly S3_PREFIX="backups"
readonly LOG_FILE="/var/log/gitea-backup.log"

readonly DB_CONTAINER="gitea-postgres"
readonly DB_USER="gitea"
readonly DB_NAME="gitea"
readonly DATA_VOLUME="gitea_gitea-data"

# Output colors
readonly GREEN='\033[0;32m'
readonly YELLOW='\033[1;33m'
readonly RED='\033[0;31m'
readonly NC='\033[0m'

# ============================================================================
# Logging Functions
# ============================================================================
log_info() {
    echo -e "${YELLOW}[INFO]${NC} $1" | tee -a "${LOG_FILE}"
}

log_success() {
    echo -e "${GREEN}[SUCCESS]${NC} $1" | tee -a "${LOG_FILE}"
}

log_error() {
    echo -e "${RED}[ERROR]${NC} $1" | tee -a "${LOG_FILE}" >&2
}

error_exit() {
    log_error "$1"
    cleanup
    exit 1
}

# ============================================================================
# Core Functions
# ============================================================================
cleanup() {
    if [ -d "${BACKUP_DIR}" ]; then
        rm -rf "${BACKUP_DIR}"
    fi
}

create_backup_dir() {
    mkdir -p "${BACKUP_DIR}" || error_exit "Failed to create backup directory"
}

backup_database() {
    log_info "Backing up PostgreSQL database..."
    
    docker exec "${DB_CONTAINER}" pg_dump -U "${DB_USER}" -d "${DB_NAME}" \
        | gzip > "${BACKUP_DIR}/database-${TIMESTAMP}.sql.gz" \
        || error_exit "Database backup failed"
}

backup_gitea_data() {
    log_info "Backing up Gitea data..."
    
    docker run --rm \
        -v "${DATA_VOLUME}:/data:ro" \
        -v "${BACKUP_DIR}:/backup" \
        alpine tar czf "/backup/gitea-data-${TIMESTAMP}.tar.gz" -C /data . \
        || error_exit "Gitea data backup failed"
}

upload_to_s3() {
    log_info "Uploading to S3..."
    
    local db_backup="${BACKUP_DIR}/database-${TIMESTAMP}.sql.gz"
    local data_backup="${BACKUP_DIR}/gitea-data-${TIMESTAMP}.tar.gz"
    
    aws s3 cp "${db_backup}" "s3://${S3_BUCKET}/${S3_PREFIX}/" \
        || error_exit "Failed to upload database backup"
    
    aws s3 cp "${data_backup}" "s3://${S3_BUCKET}/${S3_PREFIX}/" \
        || error_exit "Failed to upload Gitea data backup"
}

# ============================================================================
# Main Execution
# ============================================================================
main() {
    log_info "Starting backup process..."
    
    create_backup_dir
    backup_database
    backup_gitea_data
    upload_to_s3
    cleanup
    
    log_success "Backup completed successfully"
    log_info "Database: s3://${S3_BUCKET}/${S3_PREFIX}/database-${TIMESTAMP}.sql.gz"
    log_info "Data: s3://${S3_BUCKET}/${S3_PREFIX}/gitea-data-${TIMESTAMP}.tar.gz"
}

main "$@"