#!/bin/bash

# Setup namespace station - the infrastructure service for a namespace
# Handles service registry and shared configuration

set -euo pipefail

SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
source "$SCRIPT_DIR/lib.sh"

# Parameters
NAS_SERVER="${1:-}"
TIN_NAMESPACE="${TIN_NAMESPACE:-dynamicalsystem}"

# Setup logging functions using shared lib
log() {
    log_with_prefix "Station Setup" "$@"
}

error() {
    error_with_prefix "Station Setup" "$@"
}

warn() {
    warn_with_prefix "Station Setup" "$@"
}


# Discover existing services by scanning system UIDs
discover_existing_services() {
    local namespace_num=$(get_namespace_number "$TIN_NAMESPACE")
    local services=()
    
    log "Discovering existing services in namespace '$TIN_NAMESPACE'..."
    
    # Scan for users matching our UID pattern
    # Pattern: 1${namespace_num}${service_num}${env_num}0
    for service_num in {1..9}; do
        for env_num in 0 1; do
            local uid="1${namespace_num}${service_num}${env_num}0"
            
            if getent passwd "$uid" >/dev/null 2>&1; then
                local username=$(getent passwd "$uid" | cut -d: -f1)
                local env_name=$([[ "$env_num" == "0" ]] && echo "prod" || echo "test")
                
                # Extract service name from username pattern: service-env
                if [[ "$username" =~ ^([^-]+)-${env_name}$ ]]; then
                    local service_name="${BASH_REMATCH[1]}"
                    log "Found: $service_name ($env_name) - UID $uid (user: $username)"
                    services+=("$service_name=$service_num")
                else
                    log "Found UID $uid but couldn't parse service name from username: $username"
                fi
            fi
        done
    done
    
    # Return unique service mappings
    printf '%s\n' "${services[@]}" | sort -u
}

# Create service registry from discovered services
create_service_registry() {
    local mount_point="/mnt/station-prod"
    local registry_file="$mount_point/state/service-registry"
    
    # Create state directory
    sudo -u station-prod mkdir -p "$mount_point/state"
    
    # Discover services
    local services=$(discover_existing_services)
    
    # Create registry file
    cat << EOF | sudo -u station-prod tee "$registry_file" > /dev/null
# Service Registry for $TIN_NAMESPACE namespace
# Format: service_name=service_number

station=0
EOF
}

# Setup station user and mount using shared mount_nas.sh
setup_station_mount() {
    # Station mount setup delegated to mount_nas.sh - no additional logging needed
    if ! "$SCRIPT_DIR/mount_nas.sh" "station" "prod" "$NAS_SERVER"; then
        error "Failed to setup station NFS mount"
    fi
}

# Main setup flow
main() {
    if [[ -z "$NAS_SERVER" ]]; then
        echo "Usage: $0 <nas_server>"
        echo ""
        echo "Sets up the namespace station for service registry and shared config"
        exit 1
    fi
    
    log "Setting up station:"
    log "  Namespace: $TIN_NAMESPACE"
    log "  NFS mount: /mnt/station-prod"
    log "  User: station-prod (UID: 11000)"
    
    # Setup station mount and user (mount_nas.sh handles existence check and creation guidance)
    setup_station_mount
    
    # Step 3: Create service registry
    create_service_registry
    
    log "Station setup complete!"
    log "  Registry: /mnt/station-prod/state/service-registry"
}

main "$@"