#!/bin/bash

# Calejo Control Adapter - Remote SSH Deployment Script
# Deploys the application to remote servers over SSH

set -e

# Colors for output
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
BLUE='\033[0;34m'
NC='\033[0m' # No Color

# Default configuration
CONFIG_FILE=""
ENVIRONMENT=""
DRY_RUN=false
VERBOSE=false

# Function to print colored output
print_status() {
    echo -e "${BLUE}[INFO]${NC} $1"
}

print_success() {
    echo -e "${GREEN}[SUCCESS]${NC} $1"
}

print_warning() {
    echo -e "${YELLOW}[WARNING]${NC} $1"
}

print_error() {
    echo -e "${RED}[ERROR]${NC} $1"
}

# Function to display usage
usage() {
    echo "Usage: $0 -e <environment> [-c <config-file>] [--dry-run] [--verbose]"
    echo ""
    echo "Options:"
    echo "  -e, --environment    Deployment environment (production, staging)"
    echo "  -c, --config         Custom configuration file"
    echo "  --dry-run            Show what would be deployed without actually deploying"
    echo "  --verbose            Enable verbose output"
    echo "  -h, --help           Show this help message"
    echo ""
    echo "Examples:"
    echo "  $0 -e staging                    # Deploy to staging"
    echo "  $0 -e production --dry-run      # Dry run for production"
    echo "  $0 -e production -c custom.yml  # Use custom config"
}

# Function to parse command line arguments
parse_arguments() {
    while [[ $# -gt 0 ]]; do
        case $1 in
            -e|--environment)
                ENVIRONMENT="$2"
                shift 2
                ;;
            -c|--config)
                CONFIG_FILE="$2"
                shift 2
                ;;
            --dry-run)
                DRY_RUN=true
                shift
                ;;
            --verbose)
                VERBOSE=true
                shift
                ;;
            -h|--help)
                usage
                exit 0
                ;;
            *)
                print_error "Unknown option: $1"
                usage
                exit 1
                ;;
        esac
    done
    
    # Validate required arguments
    if [[ -z "$ENVIRONMENT" ]]; then
        print_error "Environment is required"
        usage
        exit 1
    fi
    
    # Set default config file if not provided
    if [[ -z "$CONFIG_FILE" ]]; then
        CONFIG_FILE="deploy/config/${ENVIRONMENT}.yml"
    fi
    
    # Validate config file exists
    if [[ ! -f "$CONFIG_FILE" ]]; then
        print_error "Configuration file not found: $CONFIG_FILE"
        echo "Available configurations:"
        ls -1 deploy/config/*.yml 2>/dev/null | sed 's|deploy/config/||' || echo "  (none)"
        exit 1
    fi
}

# Function to load configuration
load_configuration() {
    print_status "Loading configuration from: $CONFIG_FILE"
    
    # Check if yq is available for YAML parsing
    if ! command -v yq &> /dev/null; then
        print_error "yq is required for YAML parsing. Install with: apt-get install yq"
        exit 1
    fi
    
    # Extract configuration values (yq with jq syntax)
    SSH_HOST=$(yq -r '.ssh.host' "$CONFIG_FILE")
    SSH_PORT=$(yq -r '.ssh.port' "$CONFIG_FILE")
    SSH_USERNAME=$(yq -r '.ssh.username' "$CONFIG_FILE")
    SSH_KEY_FILE=$(yq -r '.ssh.key_file' "$CONFIG_FILE")
    
    TARGET_DIR=$(yq -r '.deployment.target_dir' "$CONFIG_FILE")
    BACKUP_DIR=$(yq -r '.deployment.backup_dir' "$CONFIG_FILE")
    LOG_DIR=$(yq -r '.deployment.log_dir' "$CONFIG_FILE")
    CONFIG_DIR=$(yq -r '.deployment.config_dir' "$CONFIG_FILE")
    
    # Validate required configuration
    if [[ -z "$SSH_HOST" || -z "$SSH_USERNAME" || -z "$SSH_KEY_FILE" ]]; then
        print_error "Missing required SSH configuration in $CONFIG_FILE"
        exit 1
    fi
    
    # Validate SSH key file exists
    if [[ ! -f "$SSH_KEY_FILE" ]]; then
        print_error "SSH key file not found: $SSH_KEY_FILE"
        echo "Available keys:"
        ls -1 deploy/keys/ 2>/dev/null || echo "  (none)"
        exit 1
    fi
    
    # Set default port if not specified
    if [[ -z "$SSH_PORT" ]]; then
        SSH_PORT=22
    fi
    
    if [[ "$VERBOSE" == "true" ]]; then
        print_status "Configuration loaded:"
        echo "  SSH Host: $SSH_HOST"
        echo "  SSH Port: $SSH_PORT"
        echo "  SSH Username: $SSH_USERNAME"
        echo "  SSH Key: $SSH_KEY_FILE"
        echo "  Target Directory: $TARGET_DIR"
    fi
}

# Function to build SSH command
build_ssh_command() {
    local cmd="$1"
    local ssh_opts="-o StrictHostKeyChecking=no -o UserKnownHostsFile=/dev/null -o ConnectTimeout=30"
    
    if [[ "$VERBOSE" == "true" ]]; then
        ssh_opts="$ssh_opts -v"
    fi
    
    echo "ssh -i $SSH_KEY_FILE -p $SSH_PORT $ssh_opts $SSH_USERNAME@$SSH_HOST '$cmd'"
}

# Function to execute remote command
execute_remote() {
    local cmd="$1"
    local description="$2"
    
    print_status "$description"
    
    if [[ "$DRY_RUN" == "true" ]]; then
        echo "  [DRY RUN] Would execute: $cmd"
        return 0
    fi
    
    local ssh_cmd=$(build_ssh_command "$cmd")
    
    if [[ "$VERBOSE" == "true" ]]; then
        echo "  Executing: $ssh_cmd"
    fi
    
    if eval "$ssh_cmd"; then
        print_success "$description completed"
        return 0
    else
        print_error "$description failed"
        return 1
    fi
}

# Function to transfer files
transfer_files() {
    local local_path="$1"
    local remote_path="$2"
    local description="$3"
    
    print_status "$description"
    
    if [[ "$DRY_RUN" == "true" ]]; then
        echo "  [DRY RUN] Would transfer: $local_path -> $SSH_USERNAME@$SSH_HOST:$remote_path"
        return 0
    fi
    
    local scp_cmd="scp -i $SSH_KEY_FILE -P $SSH_PORT -o StrictHostKeyChecking=no -o UserKnownHostsFile=/dev/null -r $local_path $SSH_USERNAME@$SSH_HOST:$remote_path"
    
    if [[ "$VERBOSE" == "true" ]]; then
        echo "  Executing: $scp_cmd"
    fi
    
    if eval "$scp_cmd"; then
        print_success "$description completed"
        return 0
    else
        print_error "$description failed"
        return 1
    fi
}

# Function to check remote prerequisites
check_remote_prerequisites() {
    print_status "Checking remote prerequisites..."
    
    # Check Docker
    execute_remote "command -v docker" "Checking Docker installation" || {
        print_error "Docker is not installed on remote server"
        return 1
    }
    
    # Check Docker Compose
    execute_remote "command -v docker-compose" "Checking Docker Compose installation" || {
        print_error "Docker Compose is not installed on remote server"
        return 1
    }
    
    # Check disk space
    execute_remote "df -h /" "Checking disk space"
    
    print_success "Remote prerequisites check passed"
}

# Function to create remote directories
create_remote_directories() {
    print_status "Creating remote directories..."
    
    local dirs=("$TARGET_DIR" "$BACKUP_DIR" "$LOG_DIR" "$CONFIG_DIR")
    
    for dir in "${dirs[@]}"; do
        execute_remote "sudo mkdir -p $dir && sudo chown $SSH_USERNAME:$SSH_USERNAME $dir" "Creating directory: $dir"
    done
    
    print_success "Remote directories created"
}

# Function to backup existing deployment
backup_existing_deployment() {
    print_status "Checking for existing deployment..."
    
    # Check if target directory exists and has content
    if execute_remote "[ -d $TARGET_DIR ] && [ \"$(ls -A $TARGET_DIR)\" ]" "Checking existing deployment" 2>/dev/null; then
        print_warning "Existing deployment found, creating backup..."
        
        local timestamp=$(date +%Y%m%d_%H%M%S)
        local backup_file="calejo-backup-$timestamp.tar.gz"
        
        execute_remote "cd $TARGET_DIR && tar -czf $BACKUP_DIR/$backup_file ." "Creating backup: $backup_file"
        
        print_success "Backup created: $BACKUP_DIR/$backup_file"
    else
        print_status "No existing deployment found"
    fi
}

# Function to transfer application files
transfer_application() {
    print_status "Transferring application files..."
    
    # Create temporary deployment package
    local temp_dir=$(mktemp -d)
    local package_name="calejo-deployment-$(date +%Y%m%d_%H%M%S).tar.gz"
    
    # Copy files to temporary directory (excluding deployment config and keys)
    print_status "Creating deployment package..."
    cp -r . "$temp_dir/"
    
    # Remove sensitive deployment files from package
    rm -rf "$temp_dir/deploy/config"
    rm -rf "$temp_dir/deploy/keys"
    
    # Create package
    cd "$temp_dir" && tar -czf "/tmp/$package_name" . && cd - > /dev/null
    
    # Transfer package
    transfer_files "/tmp/$package_name" "$TARGET_DIR/" "Transferring deployment package"
    
    # Extract package on remote
    execute_remote "cd $TARGET_DIR && tar -xzf $package_name && rm $package_name" "Extracting deployment package"
    
    # Clean up
    rm -rf "$temp_dir"
    rm -f "/tmp/$package_name"
    
    print_success "Application files transferred"
}

# Function to setup remote configuration
setup_remote_configuration() {
    print_status "Setting up remote configuration..."
    
    # Transfer configuration files
    if [[ -f "config/settings.py" ]]; then
        transfer_files "config/settings.py" "$CONFIG_DIR/" "Transferring configuration file"
    fi
    
    # Set permissions on scripts
    execute_remote "chmod +x $TARGET_DIR/scripts/*.sh" "Setting script permissions"
    execute_remote "chmod +x $TARGET_DIR/deploy-onprem.sh" "Setting deployment script permissions"
    
    print_success "Remote configuration setup completed"
}

# Function to build and start services
build_and_start_services() {
    print_status "Building and starting services..."
    
    # Build services
    execute_remote "cd $TARGET_DIR && sudo docker-compose build" "Building Docker images"
    
    # Start services
    execute_remote "cd $TARGET_DIR && sudo docker-compose up -d" "Starting services"
    
    # Wait for services to be ready
    print_status "Waiting for services to start..."
    for i in {1..30}; do
        if execute_remote "curl -s http://localhost:8080/health > /dev/null" "Checking service health" 2>/dev/null; then
            print_success "Services started successfully"
            break
        fi
        echo "   Waiting... (attempt $i/30)"
        sleep 2
        
        if [[ $i -eq 30 ]]; then
            print_error "Services failed to start within 60 seconds"
            execute_remote "cd $TARGET_DIR && sudo docker-compose logs" "Checking service logs"
            return 1
        fi
    done
}

# Function to validate deployment
validate_deployment() {
    print_status "Validating deployment..."
    
    # Run remote validation script
    if execute_remote "cd $TARGET_DIR && ./validate-deployment.sh" "Running deployment validation" 2>/dev/null; then
        print_success "Deployment validation passed"
    else
        print_warning "Deployment validation completed with warnings"
    fi
    
    # Test key endpoints
    local endpoints=("/health" "/dashboard" "/api/v1/status")
    
    for endpoint in "${endpoints[@]}"; do
        if execute_remote "curl -s -f http://localhost:8080$endpoint > /dev/null" "Testing endpoint: $endpoint" 2>/dev/null; then
            print_success "Endpoint $endpoint is accessible"
        else
            print_error "Endpoint $endpoint is not accessible"
        fi
    done
}

# Function to display deployment summary
display_deployment_summary() {
    print_success "Deployment to $ENVIRONMENT completed successfully!"
    echo ""
    echo "=================================================="
    echo "            DEPLOYMENT SUMMARY"
    echo "=================================================="
    echo ""
    echo "🌍 Environment: $ENVIRONMENT"
    echo "🏠 Server: $SSH_HOST"
    echo "📁 Application: $TARGET_DIR"
    echo ""
    echo "🔗 Access URLs:"
    echo "   Dashboard:      http://$SSH_HOST:8080/dashboard"
    echo "   REST API:       http://$SSH_HOST:8080"
    echo "   Health Check:   http://$SSH_HOST:8080/health"
    echo ""
    echo "🔧 Management Commands:"
    echo "   View logs:      ssh -i $SSH_KEY_FILE $SSH_USERNAME@$SSH_HOST 'cd $TARGET_DIR && docker-compose logs -f'"
    echo "   Health check:   ssh -i $SSH_KEY_FILE $SSH_USERNAME@$SSH_HOST 'cd $TARGET_DIR && ./scripts/health-check.sh'"
    echo "   Backup:         ssh -i $SSH_KEY_FILE $SSH_USERNAME@$SSH_HOST 'cd $TARGET_DIR && ./scripts/backup-full.sh'"
    echo ""
    echo "=================================================="
}

# Main deployment function
main() {
    echo ""
    echo "🚀 Calejo Control Adapter - Remote SSH Deployment"
    echo "=================================================="
    echo ""
    
    # Parse command line arguments
    parse_arguments "$@"
    
    # Load configuration
    load_configuration
    
    # Display deployment info
    echo "Deploying to: $ENVIRONMENT"
    echo "Server: $SSH_HOST"
    echo "Config: $CONFIG_FILE"
    if [[ "$DRY_RUN" == "true" ]]; then
        echo "Mode: DRY RUN (no changes will be made)"
    fi
    echo ""
    
    # Check remote prerequisites
    check_remote_prerequisites
    
    # Create remote directories
    create_remote_directories
    
    # Backup existing deployment
    backup_existing_deployment
    
    # Transfer application files
    transfer_application
    
    # Setup remote configuration
    setup_remote_configuration
    
    # Build and start services
    build_and_start_services
    
    # Validate deployment
    validate_deployment
    
    # Display summary
    display_deployment_summary
    
    echo ""
    print_success "Remote deployment completed!"
}

# Run main function
main "$@"