require 'errors'
require 'faraday'
require 'faraday_middleware'
require 'uri'
require 'helix_web_services_client/version'
require 'json'

# The client object handles authenticating and making calls to Helix Web Services.
#
# See our user guide online at:
# https://swarm.workshop.perforce.com/projects/perforce-software-helix-web-services/view/main/build/doc/p4ws.html#ruby_client_sdk_overview
class HelixWebServicesClient

  # The Helix Versioning Engine login
  attr_accessor :user

  # Upon successful login, we store the P4 ticket return value here.
  attr_accessor :ticket

  # Typically, Helix Web Services is mounted under /hws behind a reverse proxy.
  # If a path is specified in the originating URL, we save the prefix here,
  # and preprend it to every request.
  attr_accessor :prefix

  # The API level to use. Defaults to 78 (2015.1)
  attr_accessor :api_level

  # Some values to initialize are only used by this class, and are not passed
  # on to the Faraday initializer
  INITIALIZE_LOCAL_OPTIONS = [:user, :password, :ticket, :prefix, :api_level, :settings, :debug]

  # Client initialization can handle ensuring a valid security token to the
  # server.
  #
  # Any client created via new should take care to call `close()`.
  #
  # ## Available Options
  #
  # These options are used to configure the underlying Faraday connection:
  #
  # * `:url` - String base URL.
  # * `:params` - Hash of URI query unencoded key/value pairs.
  # * `:header` - Hash of unencoded HTTP header key/value pairs.
  # * `:request` - Hash of request options.
  # * `:ssl` - Hash of SSL options.
  # * `:proxy` - Hash of Proxy options.
  #
  # These options are specific to Helix Web Services:
  #
  # * `:user` - The Helix Versioning Engine login
  # * `:password` - If set, we will generate a ticket using this password during initialization
  # * `:ticket` - If not nil, we will use this ticket as our authentication password
  # * `:debug` - Add response logging if set to true
  #
  # @param options [Hash] See the section available options above
  def initialize(options)
    @api_level = options.key?(:api_level) ? options[:api_level] : '78'

    # Filter out options we pass to Faraday
    faraday_options = options.select { |k| !INITIALIZE_LOCAL_OPTIONS.include?(k) }

    @conn = Faraday.new(faraday_options) do |conn|
      conn.request :multipart
      conn.request :url_encoded
      conn.response :logger if options[:debug]
      conn.adapter :net_http
    end

    if options.key?(:url)
      url = URI(options[:url])
      @prefix = url.path ? url.path : ''
    end

    @user = options[:user] if options.key?(:user)

    @ticket = options[:ticket] if options.key?(:ticket)

    if options.key?(:settings)
      options[:settings].each do |key, value|
        add_setting(key, value)
      end
    end

    if options.key?(:password) and @user
      response = @conn.post(path_for('/auth/v1/login'),
                            user: user, password: options[:password])
      assert_ok(response)
      @ticket = response.body
    end

    set_auth(user, ticket) unless ticket.nil?
  end

  def close
  end

  # Set an override for all requests.
  #
  # See "configuration" in HWS documentation.
  #
  # This will automatically add the right prefix for overriding an HWS setting.
  #
  # @param key {String} The setting value as indicated in documentation, e.g., `P4PORT`
  # @param value {String} The value to set
  def add_setting(key, value)
    # Note: Rack will automatically convert all hyphens to underscores...
    # but Nginx will (by default) block all underscores. Find a happy middle.
    @conn.headers["X-Perforce-Helix-Web-Services-#{key.gsub('_', '-')}"] = value
  end

  # Remove a setting added via add_setting
  def remove_setting(key)
    @conn.headers.delete("X-Perforce-Helix-Web-Services-#{key}")
  end

  # Provides standard I/O style interface, where when called in a block,
  # will automatically close() the client when done. Otherwise, your code
  # should call client.close() manually.
  def self.open(connection)
    client = Client.new(connection)

    if block_given?
      yield client
    else
      return client
    end
  ensure
    client.close if block_given? && client
  end

  # Note: this class is really just common implementation. Methods are
  # generally defined in other files that reopen this class.

  def set_auth(user, token)
    @conn.basic_auth(user, token)
  end

  def p4_ticket?(str)
    /^[a-zA-Z0-9]{32,}$/.match(str) != nil
  end

  # Runs the method against Helix Web Services, checks for errors, then parses
  # the JSON response.
  #
  # @param method [Symbol] HTTP method, for example, :get, :post, :delete
  # @param path [String] URL path part (no URI parameters) for the method
  # @param params [Hash] URI parameters to send in
  def execute_method_no_body(method, path, params = nil)
    response = run_method_no_body(method, path, params)
    JSON.parse(response.body) if response.body && !response.body.empty?
  end

  # Runs the method against Helix Web Services, checks for errors, then parses
  # the JSON response.
  #
  # This variation will send the body (expected to be a Hash) as JSON to the
  # server.
  #
  # @param method [Symbol] HTTP method, for example, :get, :post, :delete
  # @param path [String] URL path part (no URI parameters) for the method
  # @param params [Hash] URI parameters to send in
  # @param body [Hash] The Request content (which will be converted to JSON)
  def execute_method_with_body(method, path, params = nil, body = nil)
    response = run_method_with_body(method, path, params, body)
    JSON.parse(response.body) if response.body && !response.body.empty?
  end

  def run_method_no_body(method, path, params = nil)
    path = path_for(path)

    response = @conn.send(method, path, params)
    assert_ok(response)
    response
  end

  def run_method_with_body(method, path, params = nil, body = nil)
    if !body && params
      body = params
      params = nil
    end

    path = path_for(path)

    if params
      params_hash = Faraday::Utils::ParamsHash.new
      params_hash.merge!(params)
      path += "?#{params_hash.to_query}"
    end

    response = @conn.send(method, path, body)
    assert_ok(response)
    response
  end

  # Basically just prepends the prefix to our subpath, typically, '/p4'.
  def path_for(subpath)
    if @prefix.nil? || @prefix.empty?
      subpath
    elsif subpath.nil? or subpath.empty?
      @prefix
    else
      File.join(@prefix, subpath)
    end
  end

  # Raises an error when the response is not 200. Some errors may have
  # diagnostic information in the response body, so we pass that on as well
  def assert_ok(response)
    return unless response.status >= 400
    if response.status == 400
      begin
        messages = JSON.parse(response.body)
      rescue Exception
        messages = response.body
      end
      fail Errors::BadRequest.new(messages)
    elsif response.status == 403
      fail Errors::Unauthenticated.new, 'Illegal login or password'
    elsif response.status == 404
      fail Errors::ResourceNotFound.new, 'Required resource not found'
    elsif response.status == 500 && response.body
      messages = nil
      begin
        messages = JSON.parse(response.body)
      rescue Exception => e
        messages = response.body
      end
      fail Errors::PerforceProblem.new(messages),
           'Unknown issue from the Perforce server'
    else
      fail Errors::ServerError.new, "Unknown problem. Response code: #{response.status}"
    end
  end

  def hve_path(subpath)
    "/helix_versioning_engine/v#{api_level}/#{subpath}"
  end

  # Return the product version ID of the Helix Web Services instance
  def version
    response = run_method_no_body(:get, '/status')
    response.headers['X-Helix-Web-Services-Version']
  end
end

require 'helix_web_services_client/branches'
require 'helix_web_services_client/changes'
require 'helix_web_services_client/clients'
require 'helix_web_services_client/commands'
require 'helix_web_services_client/config'
require 'helix_web_services_client/counters'
require 'helix_web_services_client/depots'
require 'helix_web_services_client/files'
require 'helix_web_services_client/groups'
require 'helix_web_services_client/helix_sync'
require 'helix_web_services_client/jobs'
require 'helix_web_services_client/labels'
require 'helix_web_services_client/login'
require 'helix_web_services_client/projects'
require 'helix_web_services_client/protections'
require 'helix_web_services_client/servers'
require 'helix_web_services_client/streams'
require 'helix_web_services_client/triggers'
require 'helix_web_services_client/users'
require 'helix_web_services_client/git_fusion_repo'
require 'helix_web_services_client/git_fusion_keys'

require_relative '../../helix_web_services/lib/hws_strings'