#!/bin/bash

# Calejo Control Adapter Restore Script
# This script restores the database and configuration from backups

set -e

# Configuration
BACKUP_DIR="/backups/calejo"

# Colors for output
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
NC='\033[0m' # No Color

# Logging function
log() {
    echo -e "${GREEN}[$(date +'%Y-%m-%d %H:%M:%S')]${NC} $1"
}

warn() {
    echo -e "${YELLOW}[$(date +'%Y-%m-%d %H:%M:%S')] WARNING:${NC} $1"
}

error() {
    echo -e "${RED}[$(date +'%Y-%m-%d %H:%M:%S')] ERROR:${NC} $1"
    exit 1
}

# Function to list available backups
list_backups() {
    echo "Available backups:"
    echo "=================="
    
    for manifest in "$BACKUP_DIR"/backup_manifest_*.txt; do
        if [ -f "$manifest" ]; then
            backup_id=$(basename "$manifest" | sed 's/backup_manifest_\\(.*\\).txt/\\1/')
            echo "Backup ID: $backup_id"
            grep -E "Backup Date:|Backup Size Summary:" "$manifest" | head -2
            echo "---"
        fi
    done
}

# Function to validate backup files
validate_backup() {
    local backup_id="$1"
    
    local db_backup="$BACKUP_DIR/calejo_db_backup_${backup_id}.sql.gz"
    local config_backup="$BACKUP_DIR/calejo_config_backup_${backup_id}.tar.gz"
    local manifest="$BACKUP_DIR/backup_manifest_${backup_id}.txt"
    
    if [ ! -f "$db_backup" ]; then
        error "Database backup file not found: $db_backup"
    fi
    
    if [ ! -f "$config_backup" ]; then
        error "Configuration backup file not found: $config_backup"
    fi
    
    if [ ! -f "$manifest" ]; then
        warn "Backup manifest not found: $manifest"
    fi
    
    log "Backup validation passed for ID: $backup_id"
}

# Function to restore database
restore_database() {
    local backup_id="$1"
    local db_backup="$BACKUP_DIR/calejo_db_backup_${backup_id}.sql.gz"
    
    log "Restoring database from: $db_backup"
    
    # Stop application if running
    if command -v docker-compose &> /dev/null && docker-compose ps | grep -q "calejo-control-adapter"; then
        log "Stopping Calejo Control Adapter..."
        docker-compose stop calejo-control-adapter
    fi
    
    if command -v docker-compose &> /dev/null; then
        # Using Docker Compose
        log "Dropping and recreating database..."
        docker-compose exec -T postgres psql -U calejo -c "DROP DATABASE IF EXISTS calejo;"
        docker-compose exec -T postgres psql -U calejo -c "CREATE DATABASE calejo;"
        
        log "Restoring database data..."
        gunzip -c "$db_backup" | docker-compose exec -T postgres psql -U calejo calejo
    else
        # Direct PostgreSQL connection
        if [ -z "$DATABASE_URL" ]; then
            error "DATABASE_URL environment variable not set"
        fi
        
        # Extract connection details from DATABASE_URL
        DB_HOST=$(echo "$DATABASE_URL" | sed -n 's/.*@\\([^:]*\\):.*/\\1/p')
        DB_PORT=$(echo "$DATABASE_URL" | sed -n 's/.*:\\\([0-9]*\\\)\\/.*/\\1/p')
        DB_NAME=$(echo "$DATABASE_URL" | sed -n 's/.*\\/\\\([^?]*\\\)/\\1/p')
        DB_USER=$(echo "$DATABASE_URL" | sed -n 's/.*:\\\([^:]*\\\):.*/\\1/p')
        DB_PASS=$(echo "$DATABASE_URL" | sed -n 's/.*:\\\([^@]*\\\)@.*/\\1/p')
        
        log "Dropping and recreating database..."
        PGPASSWORD="$DB_PASS" dropdb -h "$DB_HOST" -p "$DB_PORT" -U "$DB_USER" "$DB_NAME" --if-exists
        PGPASSWORD="$DB_PASS" createdb -h "$DB_HOST" -p "$DB_PORT" -U "$DB_USER" "$DB_NAME"
        
        log "Restoring database data..."
        gunzip -c "$db_backup" | PGPASSWORD="$DB_PASS" psql -h "$DB_HOST" -p "$DB_PORT" -U "$DB_USER" "$DB_NAME"
    fi
    
    log "Database restore completed successfully"
}

# Function to restore configuration
restore_configuration() {
    local backup_id="$1"
    local config_backup="$BACKUP_DIR/calejo_config_backup_${backup_id}.tar.gz"
    
    log "Restoring configuration from: $config_backup"
    
    # Backup current configuration
    if [ -d "config" ] || [ -d "logs" ]; then
        local current_backup="$BACKUP_DIR/current_config_backup_$(date +%Y%m%d_%H%M%S).tar.gz"
        log "Backing up current configuration to: $current_backup"
        tar -czf "$current_backup" config/ logs/ 2>/dev/null || warn "Some files might not have been backed up"
    fi
    
    # Extract configuration backup
    tar -xzf "$config_backup" -C .
    
    log "Configuration restore completed successfully"
}

# Function to start application
start_application() {
    log "Starting Calejo Control Adapter..."
    
    if command -v docker-compose &> /dev/null; then
        docker-compose start calejo-control-adapter
        
        # Wait for application to be healthy
        log "Waiting for application to be healthy..."
        for i in {1..30}; do
            if curl -f http://localhost:8080/health >/dev/null 2>&1; then
                log "Application is healthy"
                break
            fi
            sleep 2
        done
    else
        log "Please start the application manually"
    fi
}

# Main restore function
main_restore() {
    local backup_id="$1"
    
    if [ -z "$backup_id" ]; then
        error "Backup ID is required. Use --list to see available backups."
    fi
    
    log "Starting restore process for backup ID: $backup_id"
    
    # Validate backup
    validate_backup "$backup_id"
    
    # Show backup details
    local manifest="$BACKUP_DIR/backup_manifest_${backup_id}.txt"
    if [ -f "$manifest" ]; then
        echo
        cat "$manifest"
        echo
    fi
    
    # Confirm restore
    read -p "Are you sure you want to restore from this backup? This will overwrite current data. (y/N): " -n 1 -r
    echo
    if [[ ! $REPLY =~ ^[Yy]$ ]]; then
        log "Restore cancelled"
        exit 0
    fi
    
    # Perform restore
    restore_database "$backup_id"
    restore_configuration "$backup_id"
    start_application
    
    log "Restore completed successfully!"
    log "Backup ID: $backup_id"
    log "Application should now be running with restored data"
}

# Parse command line arguments
case "${1:-}" in
    --list|-l)
        list_backups
        exit 0
        ;;
    --help|-h)
        echo "Usage: $0 [OPTIONS] [BACKUP_ID]"
        echo ""
        echo "Options:"
        echo "  --list, -l    List available backups"
        echo "  --help, -h    Show this help message"
        echo ""
        echo "If BACKUP_ID is provided, restore from that backup"
        echo "If no arguments provided, list available backups"
        exit 0
        ;;
    "")
        list_backups
        echo ""
        echo "To restore, run: $0 BACKUP_ID"
        exit 0
        ;;
    *)
        main_restore "$1"
        ;;
esac