cinch markov bot

main.rb

require 'cinch'
require 'cinch/plugins/identify'
require 'json'

LOOKFORWARD = 2 #how many words forward it generates from a seed word
BOTNAME = "MarkovBot"

def prepareString(str)
	#return str.downcase.split(/(\W)+/).map{|word| word.gsub(/\s+/, "")}.reject{|word| word == ""} to remind you what it was
	return str.split(/\s+/)
end

def addArrayToChain(strArray, chain)
	strArray.each_with_index do |currentStr, index|
		doneWithString = false
		LOOKFORWARD.times do |t| 
			if strArray[index + t + 1].nil? 
				doneWithString = true
			end
		end #break if no more strings can be found up ahead
		break if doneWithString

		nextStringsArray = [] #make an array of the next strings
		LOOKFORWARD.times do |t| nextStringsArray << strArray[index + t + 1] end
		nextStrings = nextStringsArray.join(" ")

		if !chain.key?(currentStr)
			chain[currentStr] = {}
		end
		if !chain[currentStr].key?(nextStrings)
			chain[currentStr][nextStrings] = 0
		end
		chain[currentStr][nextStrings] += 1
	end
	File.open("markovbackup.rson", "w") { |file| file.write(JSON.generate(chain)) }
	return chain
end

def generateWords(chain, length, topic)
	topicWords = topic.split(/\s+/).reject{|word| word.include? BOTNAME}.sort_by(&:length).select{|word| word.length > 2} #select suitable-looking words for the bot to talk about
	topicWord = chain.keys.sample #fallback to a random topic
	topicWords.each do |word| #try to make the bot talk about them
		if !chain[word].nil?
			topicWord = word
			break
		end
	end

	outputString = []
	outputString << topicWord #put the first seed word in
	length.times do |currentLength|
		lastWord = outputString.last.split(" ").last #this is gross, splits the last phrase to get the last word to use as the next seed
		break if chain[lastWord].nil? #if there aren't words to complete the phrase

		chanceTable = chain[lastWord]

		cdf = 0 #calculating the weighted random, warning: gross
		chanceTable.each do |weight|
			cdf += weight[1]
		end
		randomInt = rand(cdf)
		runningSum = 0
		chanceTable.each_pair do |word, weight|
			runningSum += weight
			if runningSum > randomInt
				outputString << word
				break
			end
		end
	end
	return outputString.join(" ")
end

class MarkovIRC
	include Cinch::Plugin

	match /.+/, use_prefix: false #run on anything said

	def execute(m)
		@@permChain = addArrayToChain(prepareString(m.message), @@permChain)
		if m.message.include? BOTNAME
			if m.channel.name != "#roblox-bots"
				Target(m.user.nick).send("#{generateWords(@@permChain, rand(5)+20, m.message)}")
			else
				m.reply("#{m.user.nick}: #{generateWords(@@permChain, rand(5)+20, m.message)}")
				#m.reply("NotBoringAces: #{generateWords(@@permChain, rand(5)+20, m.message)}")
			end
		end
	end
end

bot = Cinch::Bot.new do
	configure do |c|
		c.server = "irc.freenode.org"
		c.nick = BOTNAME
		c.channels = ["#roblox-bots", "#roblox"]
		c.delay_joins = :identified
		c.plugins.plugins = [MarkovIRC, Cinch::Plugins::Identify]
		c.plugins.options[Cinch::Plugins::Identify] = {
			:username => "Aearnus",
			:password => <dfnsdikfnsdk>,
			:type => :nickserv
		}
	end
end

@@permChain = JSON.parse(File.read("markovbackup.rson"))
sampleText = File.read("sampletext")
@@permChain = addArrayToChain(prepareString(sampleText), @@permChain)
bot.start