require 'net/http'
require 'rubygems'
require 'json'

class StatsMix
  
  BASE_URI = 'https://statsmix.com/api/v2/'
  
  GEM_VERSION = File.exist?('../VERSION') ? File.read('../VERSION') : ""

  # Track an event
  # 
  # Required: name of metric
  # Optional: value, options {:generated_at}
  # Returns: Net::HTTP object
  def self.track(name, value = nil, options = {})
    self.connect('track')
    @request_uri = @url.path + '.' + @format
    @request = Net::HTTP::Get.new(@request_uri)
    @params[:name] = name
    if @test_metric_name
      @params[:name] = @test_metric_name
    end
    @params[:value] = value if value != nil
    @params.merge!(options)
    @params[:meta] =
    if @params[:meta] && !@params[:meta].is_a?(String)
      if @params[:meta].respond_to?('to_json')
        @params[:meta] = @params[:meta].to_json
      end
    end
    return do_request
  end
  # Stats
  
  # List stats (index)
  # 
  # Required: metric_id
  # Optional: limit
  # Returns: Net::HTTP object
  def self.list_stats(metric_id, limit = nil)
    self.connect('stats')
    @request_uri = @url.path + '.' + @format
    @request = Net::HTTP::Get.new(@request_uri)
    @params[:metric_id] = metric_id
    @params[:limit] = limit if limit != nil
    return do_request
  end
  
  # Get stat
  # 
  # Required: stat_id
  # Optional: none
  # Returns: Net::HTTP object
  def self.get_stat(stat_id)
    connect('stats')
    @request_uri = @url.path + '/' + stat_id.to_s + '.' + @format
    @request = Net::HTTP::Get.new(@request_uri)
    return do_request
  end
  
  # Create stat
  # 
  # Required: metric_id
  # Optional: value, params[:generated_at, :meta]
  # Returns: Net::HTTP object
  def self.create_stat(metric_id, value = nil, params = {})
    connect('stats')
    @request_uri = @url.path + '.' + @format
    @request = Net::HTTP::Post.new(@request_uri)
    @params.merge!(params)
    @params[:value] = value if value
    return do_request
  end
  
  # Update stat
  # 
  # Required: stat_id
  # Optional: value, generated_at, meta
  # Returns: Net::HTTP object
  def self.update_stat(stat_id, value = nil, params = {})  
    connect('stats')
    @request_uri = @url.path + '/' + stat_id.to_s + '.' + @format
    @request = Net::HTTP::Put.new(@request_uri)
    @params.merge!(params)
    @params[:value] = value if value != nil
    return do_request
  end
  
  # Delete stat
  # 
  # Required: stat_id
  # Optional: none
  # Returns: Net::HTTP object
  def self.delete_stat(stat_id)    
    connect('stats')
    @request_uri = @url.path + '/' + stat_id.to_s + '.' + @format
    @request = Net::HTTP::Delete.new(@request_uri)
    return do_request
  end
  
  # Metrics
  
  # List metrics
  # 
  # Required: none
  # Optional: profile_id, limit
  # Returns: Net::HTTP object
  def self.list_metrics(profile_id = nil, limit = nil)
    connect('metrics')
    @request_uri = @url.path + '.' + @format
    @request = Net::HTTP::Get.new(@request_uri)

    @params[:profile_id] = profile_id if profile_id  != nil
    @params[:limit] = limit if limit != nil
    
    return do_request
  end
  
  # Get metric
  # 
  # Required: metric_id
  # Optional: none
  # Returns: Net::HTTP object
  def self.get_metric(metric_id)
    connect('metrics')
    @request_uri = @url.path + '/' + metric_id.to_s + '.' + @format
    @request = Net::HTTP::Get.new(@request_uri)
    return do_request
  end
  
  # Create metric
  # 
  # Required: name
  # Optional: params[:profile_id, :sharing, :include_in_email]
  # Returns: Net::HTTP object
  def self.create_metric(name,params={})
    connect('metrics')
    @params.merge!(params)
    @params[:name] = name
    @request_uri = @url.path + '.' + @format
    @request = Net::HTTP::Post.new(@request_uri)
    return do_request
  end
  
  # Update metric
  # 
  # Required: metric_id
  # Optional: params[:profile_id, :sharing, :include_in_email]
  # Returns: Net::HTTP object
  def self.update_metric(metric_id, params = {})  
    connect('metrics')
    @params = [] if @params.nil?
    @params.merge!(params)
    @request_uri = @url.path + '/' + metric_id.to_s + '.' + @format
    @request = Net::HTTP::Put.new(@request_uri)

    return do_request
  end
  
  # Delete metric
  # 
  # Required: metric_id
  # Optional: none
  # Returns: Net::HTTP object
  def self.delete_metric(metric_id)    
    connect('metrics')
    @request_uri = @url.path + '/' + metric_id.to_s + '.' + @format
    @request = Net::HTTP::Delete.new(@request_uri)
    return do_request
  end
  
  def initialize(api_key = nil)
    self.setup(api_key)
  end
  
  # Returns: Net::HTTP object
  def self.response
    @response
  end
  
  # Returns: string or boolean false
  def self.error
    @error
  end
  
  # Returns: hash
  def self.params
    @params
  end
  
  def self.api_key=(string)
    @api_key = string
  end
  
  # Returns: string
  def self.api_key
    @api_key
  end
  
  def self.ignore=(boolean)
    @ignore = boolean ? true : false
  end
  
  #Returns: boolean
  def self.ignore
    @ignore
  end
  
  def self.test_metric_name=(name)
    @test_metric_name = name
  end
  
  #Returns: string or nil
  def self.test_metric_name
    @test_metric_name
  end
  
  # Returns: string
  def self.api_key
    @api_key
  end
  
  def self.api_from_env
    return nil if ENV['STATSMIX_URL'].nil?
    url = ENV['STATSMIX_URL']
    pieces = url.gsub('http://','').gsub('https://','').split('/')
    @api_key = pieces[2]
  end
  
  def self.format=(string)
    string.downcase!
    if string != 'json' && string != 'xml'
      raise "format MUST be either xml or json"
    end
    @format = string
  end
  
  # Returns: string
  def self.format
    @format
  end
  
  # Returns: string
  def self.request_uri
    @request_uri
  end
  private
  
  def self.setup(api_key = nil)
    return if @initiliazed
    if !api_key.nil?
      @api_key = api_key
    end
    @format = 'xml' if @format.nil?
    @ignore = false if @ignore.nil?
    @user_agent = "StatsMix Ruby Gem " + GEM_VERSION
    @initiliazed = true
    @error = false
  end
  
  def self.connect(resource)
    self.setup
    
    if @api_key.nil?
      raise "API key not set. You must set it frist with StatsMix.api_key = [your api key]"
    end
    # Resources available: stats, metrics, TODO: profiles
    @url = URI.parse(BASE_URI + resource)
    @connection = Net::HTTP.new(@url.host, @url.port)
    
    @request = Hash.new
    @request["User-Agent"] = @user_agent
    @params = Hash.new
    @params[:api_key] = @api_key
  end
  
  def self.do_request
    @error = false
    return if @ignore
    @request.set_form_data(@params)
    @response = @connection.request(@request)
    if @response.is_a?(Net::HTTPClientError)
      if 'xml' == @format
        begin
          @error = @response.body.match('<error>(.)+</error>')[0].gsub('<error>','').gsub('</error>','')
        rescue
          @error = 'Unable to parse error message. Check StatsMix.response for more information'
        end
      else
        @error = JSON.parse(@response.body)['errors']['error']
      end
    end
    @response.body
  end
end

StatsMix.api_from_env