module Concurrency

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

# File lib/concurrency.rb, line 33
def self.conversion_rate(from = Concurrency.configuration.from_currency, to = Concurrency.configuration.to_currency)
    if from == to
        return 1.0
    else
        rate = Concurrency.get_rate(from, to)
        return rate
    end
end

# File lib/concurrency.rb, line 23
def self.convert(*args)
    if args.length == 3
        Concurrency.convert_full(*args)
    elsif args.length == 2
        Concurrency.convert_full(args[0], Concurrency.configuration.from_currency, args[1])
    else
        Concurrency.convert_full(args[0], Concurrency.configuration.from_currency, Concurrency.configuration.to_currency)
    end
end

# File lib/concurrency.rb, line 15
def self.reset
    @configuration = Configuration.new
end

# File lib/concurrency.rb, line 44
def self.convert_full(initial, from, to)
    if from == to
        return initial
    end
    rate = Concurrency.get_rate(from, to)
    if rate == nil
        return nil
    else
        return initial*rate
    end
end

# File lib/concurrency.rb, line 56
def self.get_rate(from, to)
    puts "From:#{from}>>TO:#{to}>>APIKEY:#{Concurrency.configuration.api_key}"
    if Concurrency.configuration.api_key.nil? 
        raise "API Key is missing. Kindly set API key CONCURRENCY_APIKEY."
    end
    url = "https://free.currencyconverterapi.com/api/v6/convert?q=#{from}_#{to}&compact=ultra&apiKey=#{Concurrency.configuration.api_key}"
    uri = URI(url)
    response = Net::HTTP.get(uri)
    if response == nil
        return nil
    else
        parsed_response = JSON.parse(response)
        rate = (parsed_response["#{from}_#{to}"]).to_f
        return rate
    end
end