class GCM

# File lib/gcm.rb, line 13
def initialize(api_key, client_options = {})
  @api_key = api_key
  @client_options = client_options
end

# File lib/gcm.rb, line 63
def add_registration_ids(key_name, project_id, notification_key, registration_ids)
  post_body = build_post_body(registration_ids,                     operation: 'add',
                                                                    notification_key_name: key_name,
                                                                    notification_key: notification_key)

  params = {
    body: post_body.to_json,
    headers: {
      'Content-Type' => 'application/json',
      'project_id' => project_id,
      'Authorization' => "key=#{@api_key}"
    }
  }

  response = self.class.post('/notification', params.merge(@client_options))
  build_response(response)
end

# File lib/gcm.rb, line 45
def create_notification_key(key_name, project_id, registration_ids = [])
  post_body = build_post_body(registration_ids,                   operation: 'create',
                                                                  notification_key_name: key_name)

  params = {
    body: post_body.to_json,
    headers: {
      'Content-Type' => 'application/json',
      'project_id' => project_id,
      'Authorization' => "key=#{@api_key}"
    }
  }

  response = self.class.post('/notification', params.merge(@client_options))
  build_response(response)
end

# File lib/gcm.rb, line 82
def remove_registration_ids(key_name, project_id, notification_key, registration_ids)
  post_body = build_post_body(registration_ids,                   operation: 'remove',
                                                                  notification_key_name: key_name,
                                                                  notification_key: notification_key)

  params = {
    body: post_body.to_json,
    headers: {
      'Content-Type' => 'application/json',
      'project_id' => project_id,
      'Authorization' => "key=#{@api_key}"
    }
  }

  response = self.class.post('/notification', params.merge(@client_options))
  build_response(response)
end

# File lib/gcm.rb, line 30
def send_notification(registration_ids, options = {})
  post_body = build_post_body(registration_ids, options)

  params = {
    body: post_body.to_json,
    headers: {
      'Authorization' => "key=#{@api_key}",
      'Content-Type' => 'application/json'
    }
  }
  response = self.class.post('/send', params.merge(@client_options))
  build_response(response, registration_ids)
end

# File lib/gcm.rb, line 115
def send_to_topic(topic, options = {})
  if topic =~ /[a-zA-Z0-9\-_.~%]+/
    send_with_notification_key('/topics/' + topic, options)
  end
end

# File lib/gcm.rb, line 101
def send_with_notification_key(notification_key, options = {})
  body = { to: notification_key }.merge(options)

  params = {
    body: body.to_json,
    headers: {
      'Authorization' => "key=#{@api_key}",
      'Content-Type' => 'application/json'
    }
  }
  response = self.class.post('/send', params.merge(@client_options))
  build_response(response)
end

# File lib/gcm.rb, line 148
def build_canonical_ids(body, registration_ids)
  canonical_ids = []
  unless body.empty?
    if body['canonical_ids'] > 0
      body['results'].each_with_index do |result, index|
        canonical_ids << { old: registration_ids[index], new: result['registration_id'] } if has_canonical_id?(result)
      end
    end
  end
  canonical_ids
end

# File lib/gcm.rb, line 160
def build_not_registered_ids(body, registration_id)
  not_registered_ids = []
  unless body.empty?
    if body['failure'] > 0
      body['results'].each_with_index do |result, index|
        not_registered_ids << registration_id[index] if is_not_registered?(result)
      end
    end
  end
  not_registered_ids
end

# File lib/gcm.rb, line 123
def build_post_body(registration_ids, options = {})
  { registration_ids: registration_ids }.merge(options)
end

# File lib/gcm.rb, line 127
def build_response(response, registration_ids = [])
  body = response.body || {}
  response_hash = { body: body, headers: response.headers, status_code: response.code }
  case response.code
  when 200
    response_hash[:response] = 'success'
    body = JSON.parse(body) unless body.empty?
    response_hash[:canonical_ids] = build_canonical_ids(body, registration_ids) unless registration_ids.empty?
    response_hash[:not_registered_ids] = build_not_registered_ids(body, registration_ids) unless registration_ids.empty?
  when 400
    response_hash[:response] = 'Only applies for JSON requests. Indicates that the request could not be parsed as JSON, or it contained invalid fields.'
  when 401
    response_hash[:response] = 'There was an error authenticating the sender account.'
  when 503
    response_hash[:response] = 'Server is temporarily unavailable.'
  when 500..599
    response_hash[:response] = 'There was an internal error in the GCM server while trying to process the request.'
  end
  response_hash
end

# File lib/gcm.rb, line 172
def has_canonical_id?(result)
  !result['registration_id'].nil?
end

# File lib/gcm.rb, line 176
def is_not_registered?(result)
  result['error'] == 'NotRegistered'
end