module Slimpay

# File lib/slimpay.rb, line 32
def base
  return @base if @base

  if !self.client_id || !self.client_secret
    raise "[Slimpay] client_id or client_secret not defined"
  end

  json = request(:get, '/')
  klass = generate_resource(json)

  @base = Slimpay.const_set('Base', klass).new(json)
  @base
end

# File lib/slimpay.rb, line 19
def configure
  yield(self)
end

# File lib/slimpay.rb, line 15
def initialize
  sandbox = true
end

# File lib/slimpay.rb, line 23
def sandbox
  @sandbox != false
end

# File lib/slimpay.rb, line 27
def sandbox=(value)
  @sandbox = value
  update_base_url
end

# File lib/slimpay.rb, line 52
def generate_resource(json)
  klass = Class.new do
    attr_reader :data

    def initialize(data)
      @data = data
    end
  end

  if json['_links'].present?
    json['_links'].each do |key, _|
      # Ignore `self` and `profile`
      next if !key.start_with?(Slimpay::LINK_NAMESPACE)

      path = json['_links'][key]['href'].dup
      method_name = key.sub(Slimpay::LINK_NAMESPACE, '').underscore
      http_method = :get

      # HACK: don't have the information from the API
      if method_name.start_with?('create', 'post', 'revoke', 'cancel')
        http_method = :post
      elsif method_name.start_with?('patch')
        http_method = :patch
      end

      if path.end_with?('{id}')
        klass.send(:define_method, method_name) do |id|
          new_path = path.sub('{id}', id)
          Slimpay.send(:parse_response, Slimpay.send(:request, http_method, new_path))
        end
      else
        params = []
        if json['_links'][key]['templated'].present?
          params = path.scan(/{\?(.*)}/)[0][0].split(',')
          path.sub!(/{(.*)}/, '')
        end

        # Useful for finding params
        # List only params for GET request
        klass.send(:define_method, "#{method_name}_params") do
          params
        end

        klass.send(:define_method, method_name) do |params = {}|
          Slimpay.send(:parse_response, Slimpay.send(:request, http_method, path, params))
        end
      end   
    end
  end

  if json['_embedded'].present?
    json['_embedded'].each do |key, values|
      attr_values = []

      values.each do |value|
        attr_values << generate_resource(value).new(value)
      end

      klass.send(:define_method, key) do
        attr_values
      end
    end
  end

  klass
end

# File lib/slimpay.rb, line 119
def parse_response(json)
  generate_resource(json).new(json)
end

# File lib/slimpay.rb, line 191
def refresh_token
  self.logger.debug "[Slimpay] refresh token" if self.logger

  client = OAuth2::Client.new(
    @client_id,
    @client_secret,
    site: @base_url,
    headers: {
      'grant_type' => 'client_credentials',
      'scope' => 'api_admin'
    }
  )
  response = client.client_credentials.get_token
  @token = response.token
end

# File lib/slimpay.rb, line 123
def request(method, path, params = {}, no_retry = false)
  refresh_token if @token.nil?

  self.logger.debug "[Slimpay] request: method: #{method} - path: #{path} - params: #{params}" if self.logger

  headers = {
    'Authorization' => "Bearer #{@token}",
    'Accept' => 'application/hal+json; profile="https://api.slimpay.net/alps/v1"',
    'Content-Type' => 'application/json',
  }

  url = URI.join(@base_url, path)
  http = Net::HTTP.new(url.host, url.port)
  http.use_ssl = url.scheme == 'https'

  case method
  when :get
    url.query = URI.encode_www_form(params)
    response = http.get(url, headers)
  when :post
    response = http.post(url, MultiJson.dump(params), headers)
  when :put
    response = http.put(url, MultiJson.dump(params), headers)
  when :patch
    headers['Content-Type'] = 'application/merge-patch+json'
    response = http.patch(url, MultiJson.dump(params), headers)
  when :delete
    request = Net::HTTP::Delete.new(url, headers)
    request.body = MultiJson.dump(params)

    response = http.request(request)
  else
    raise "[Slimpay] request method invalid: #{method}"
  end

  if response.is_a?(Net::HTTPSuccess)
    if response.body.blank?
      return nil
    else
      return MultiJson.load(response.body)
    end
  end

  # If get 401 Unauthorised try to have a new token and redo the request but only once
  if response.code.to_s == '401' && no_retry === false
    @token = nil
    return request(method, path, params, true)
  end

  json = MultiJson.load(response.body) rescue {}

  error_data = { 
    method: method,
    path: path,
    params: params,
    status_code: response.code,
    json: json
  }

  if json.empty?
    error_data[:body] = response.body
  end

  self.logger.error "[Slimpay] request error: #{error_data.map {|k,v| "#{k}: #{v.inspect}" }.join(' - ')}" if self.logger

  raise Slimpay::Error.new(error_data)
end

# File lib/slimpay.rb, line 48
def update_base_url
  @base_url = sandbox === false ? 'https://api.slimpay.net/' : 'https://api.preprod.slimpay.com/'
end