# frozen_string_literal: true

# Requirements
# =======================================================================

# Stdlib
# -----------------------------------------------------------------------

# Deps
# -----------------------------------------------------------------------
require 'plist'
require 'fileutils'

# Project / Package
# -----------------------------------------------------------------------


# Refinements
# =======================================================================

require 'nrser/refinements/types'
using NRSER::Types


# Definitions
# =======================================================================


# An site is a {Locd::Agent} that the proxy can route HTTP requests to.
# 
# If you send an HTTP request to the proxy with the site's label as the
# host, the proxy will start the site if it isn't running and route the
# request to it's {#port}.
# 
# Combined with DNSMasq pointing the site's label to the proxy (and using
# the port the proxy is running on) this allows you to open the site's
# {#url} in the browser (or make a request to it from anything that resolves
# DNS properly through DNSMasq... should work fine for APIs and other HTTP
# services) and get through to the agent.
# 
class Locd::Agent::Site < Locd::Agent
  
  # Constants
  # ==========================================================================
  
  # Address we expect servers to bind to so we can reach them. Provided
  # during command rendering as `{bind}` so it can be used when running
  # service commands.
  # 
  # For the moment at least this seems to need to be `127.0.0.1` 'cause I
  # think ProxyMachine had trouble connecting to `localhost`, so services
  # need to bind to it or be reachable at it.
  # 
  # @return [String]
  # 
  BIND = '127.0.0.1'.freeze
  
  
  # Attribute / method names that {#to_h} uses.
  # 
  # @return [Hamster::SortedSet<Symbol>]
  # 
  TO_H_NAMES = Locd::Agent::TO_H_NAMES.union [:port, :url]
  
  
  # Structs
  # ============================================================================

  class Status < Locd::Agent::Status
    
    # @!attribute [r] port
    #   Site backend port.
    #   
    #   @return [Integer]
    #   
    prop  :port,
          type: t.pos_int
    
  end # class Status
  
  
  # Class Methods
  # ==========================================================================
  
  
  # See if a parsed plist looks like a site.
  # 
  # @param [Hash<String, Object>] plist
  #   Property list parsed by {Plist.parse_xml}.
  # 
  # @return [Boolean]
  #    `true` if we think this `plist` belongs to a site.
  # 
  def self.plist? plist
    !!(
      plist.dig( Locd.config[:agent, :config_key], 'port' ) &&
      plist.dig( Locd.config[:agent, :config_key], 'is_system' ) != true
    )
  end # .plist?
  
  
  
  # @!group Querying
  # --------------------------------------------------------------------------
  
  # Sorted set of all ports configured for installed {Locd::Agent::Site}.
  # 
  # Used to determine available ports to allocate when creating new services.
  # 
  # @return [Hamster::SortedSet<Fixnum>]
  # 
  def self.ports
    Hamster::SortedSet.new all.values.map( &:port )
  end
  
  # @!endgroup
  
  
  # @!group Creating Servers
  # --------------------------------------------------------------------------
  
  # Create the `launchd` property list data for a new {Locd::Agent::Site}, which
  # has an additional `port:` keyword versus {Locd::Agent.create_plist_data}.
  # 
  # @param cmd_template   (see Locd::Agent.create_plist_data)
  # @param label          (see Locd::Agent.create_plist_data)
  # @param workdir        (see Locd::Agent.create_plist_data)
  # @param log_path       (see Locd::Agent.create_plist_data)
  # @param keep_alive     (see Locd::Agent.create_plist_data)
  # @param run_at_load    (see Locd::Agent.create_plist_data)
  # 
  # @param [nil | Fixnum | String] port
  #   Port to run the service on. If you don't provide one, one will be
  #   provided for you (see {Locd::Proxy.allocate_port}).
  # 
  # @param [String] bind
  #   Address that the server should bind to.
  # 
  # @return (see Locd::Agent.create_plist_data)
  # 
  def self.create_plist_data  cmd_template:,
                              label:,
                              workdir:,
                              log_path: nil,
                              keep_alive: false,
                              run_at_load: false,
                              port: nil,
                              bind: Locd.config[:site, :bind],
                              open_path: '/'
    # Allocate a port if one was not provided
    port = if port.nil?
      Locd::Proxy.allocate_port
    else
      # or just normalize to {Fixnum}
      port.to_i
    end
    
    open_path = "/#{ path }" unless open_path.start_with? '/'
    
    super cmd_template: cmd_template,
          label: label,
          workdir: workdir,
          log_path: log_path,
          keep_alive: keep_alive,
          run_at_load: run_at_load,
          # Extras specific to {Locd::Agent::Site}:
          port: port,
          bind: bind,
          open_path: open_path
  end # .create_plist_data
  
  
  # Instance Methods
  # ============================================================================
  
  # @!group Instance Methods: Attribute Readers
  # ----------------------------------------------------------------------------
  # 
  # Methods to read proxied and computed attributes.
  # 
  
  # @return [Integer]
  #   Port service runs on.
  def port
    config['port']
  end
  
  
  def open_path
    config['open_path'] || '/'
  end
  
  
  # @return [String]
  #   The URL the agent can be reached at through the proxy.
  def url
    "http://#{ label }:#{ Locd::Proxy.port }#{ open_path }"
  end
  
  # @!endgroup Instance Methods: Attribute Readers
  
  
  # @!group `launchctl` Interface Instance Methods
  # ----------------------------------------------------------------------------

  # The site agent's status from parsing `launchctl list`.
  # 
  # Status is read on demand and cached on the instance.
  # 
  # @param [Boolean] refresh:
  #   When `true`, will re-read from `launchd` (and cache results)
  #   before returning.
  # 
  # @return [Status]
  # 
  def status refresh: false
    Status.new port: port, **super( refresh: refresh )
  end
  
  # @!endgroup `launchctl` Interface Instance Methods
  
end # class Locd::Launchd