#!/bin/bash
# tin machine create - Create machine environment

set -euo pipefail

# Get tinsnip root and source libraries
SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
TINSNIP_ROOT="$(dirname "$(dirname "$SCRIPT_DIR")")"
source "$TINSNIP_ROOT/lib/core.sh"
source "$TINSNIP_ROOT/lib/uid.sh"
source "$TINSNIP_ROOT/lib/registry.sh"

# Create machine environment
create_machine() {
    local service="$1"
    local environment="$2"
    local nas_server="${3:-}"
    
    log_with_prefix "Machine Create" "Creating machine environment: $service-$environment"
    echo
    
    # Show current sheet
    local sheet=$(get_sheet)
    log_with_prefix "Machine Create" "Sheet: $sheet"
    
    # Validate sheet is registered (unless it's topsheet)
    if [[ "$sheet" != "topsheet" ]]; then
        if ! get_sheet_number "$sheet" >/dev/null 2>&1; then
            error_with_prefix "Machine Create" "Sheet '$sheet' not registered"
            echo "Register with: tin sheet create $sheet" >&2
            exit 1
        fi
    fi
    
    # Calculate expected UID
    local service_uid
    if service_uid=$(calculate_service_uid "$service" "$environment"); then
        log_with_prefix "Machine Create" "Service UID: $service_uid"
    else
        error_with_prefix "Machine Create" "Failed to calculate service UID"
        exit 1
    fi
    
    # Auto-discover NAS if not provided
    if [[ -z "$nas_server" ]]; then
        log_with_prefix "Machine Create" "Auto-discovering NAS server..."
        if nas_server=$(discover_nas_for_sheet 2>/dev/null); then
            log_with_prefix "Machine Create" "Discovered NAS server: $nas_server"
        else
            error_with_prefix "Machine Create" "No NAS server found for sheet '$sheet'"
            echo "Either:" >&2
            echo "1. Specify NAS server: tin machine create $service $environment <nas-server>" >&2
            echo "2. Register default NAS: tin registry nas add default <nas-server>" >&2
            echo "3. Register for sheet: tin registry nas add $sheet <nas-server>" >&2
            exit 1
        fi
    else
        log_with_prefix "Machine Create" "Using provided NAS server: $nas_server"
    fi
    
    echo
    echo "Configuration:"
    echo "  Service: $service"
    echo "  Environment: $environment"
    echo "  Sheet: $sheet"
    echo "  UID: $service_uid"
    echo "  NAS: $nas_server"
    echo "  Mount: /mnt/$service-$environment"
    echo
    
    # Confirm creation
    read -p "Create this machine environment? [Y/n]: " confirm
    case "${confirm:-y}" in
        [Yy]*|"")
            log_with_prefix "Machine Create" "Creating machine environment..."
            
            # Delegate to existing machine setup (pass UID to avoid duplicate warning)
            if [[ "$service" == "station" ]]; then
                exec "$TINSNIP_ROOT/machine/setup_station.sh" "$nas_server"
            else
                exec "$TINSNIP_ROOT/machine/setup_service.sh" "$service" "$environment" "$nas_server" "$service_uid"
            fi
            ;;
        [Nn]*)
            log_with_prefix "Machine Create" "Machine creation cancelled"
            exit 1
            ;;
        *)
            error_with_prefix "Machine Create" "Invalid input. Machine creation cancelled"
            exit 1
            ;;
    esac
}

show_help() {
    cat << EOF
tin machine create - Create machine environment

USAGE:
    tin machine create <service> <environment> [nas-server]
    tin machine <service> <environment>        # Shorthand

DESCRIPTION:
    Create a complete machine environment for a service including:
    - Service user with SMEP UID
    - NFS mount for persistent storage
    - Rootless Docker installation
    - XDG directory integration

ARGUMENTS:
    <service>      Service name (lowercase alphanumeric with hyphens)
    <environment>  Environment name (prod, test, dev, staging, etc.)
    [nas-server]   NAS server hostname or IP (optional if registered)

EXAMPLES:
    tin machine create gazette prod DS412plus.local
    tin machine create lldap test 192.168.1.100
    tin machine gazette prod                    # Use registered NAS

SUPPORTED ENVIRONMENTS:
    prod, test, dev, staging, demo, qa, uat, preview, canary, local

EOF
}

# Handle help flags
case "${1:-}" in
    --help|-h|help)
        show_help
        exit 0
        ;;
esac

# Main execution
if [[ $# -lt 2 ]]; then
    error_with_prefix "Machine Create" "Service and environment required"
    echo "Usage: tin machine create <service> <environment> [nas-server]" >&2
    exit 1
fi

service="$1"
environment="$2" 
nas_server="${3:-}"

# Validate service name
if [[ ! "$service" =~ ^[a-z0-9-]+$ ]]; then
    error_with_prefix "Machine Create" "Service name must be lowercase alphanumeric with hyphens only"
fi

# Validate environment name
case "$environment" in
    prod|test|dev|staging|demo|qa|uat|preview|canary|local)
        # Valid environment
        ;;
    *)
        error_with_prefix "Machine Create" "Invalid environment: $environment"
        echo "Supported: prod, test, dev, staging, demo, qa, uat, preview, canary, local" >&2
        exit 1
        ;;
esac

create_machine "$service" "$environment" "$nas_server"