dogelang.go

package main

import (
	"bufio"
	"io"
	"io/ioutil"
	"math/rand"
	"os"
	"strings"
	"time"
	"unicode"
)

func main() {
	rand.Seed(time.Now().UnixNano())
	lenToWord, err := getWordSet()
	if err != nil {
		panic(err)
	}
	br := bufio.NewReader(os.Stdin)
	currString := ""
	for {
		r, _, err := br.ReadRune()
		if err != nil {
			if err == io.EOF {
				break
			}
			panic(err)
		}
		if !unicode.IsLetter(r) {
			if len(currString) == 0 {
				_, err = os.Stdout.WriteString(string(r))
				if err != nil {
					panic(err)
				}
				currString = ""
				continue
			}
			var dogWord string
			words, ok := lenToWord[len(currString)]
			if !ok {
				dogWord = combineMultipleLengths(lenToWord, len(currString))
			} else {
				dogWord = pickRandom(words)
			}
			dogWord = matchCase(currString, dogWord)
			_, err = os.Stdout.WriteString(dogWord + string(r))
			if err != nil {
				panic(err)
			}
			currString = ""
			continue
		}
		currString += string(r)
	}
}

func matchCase(model string, s string) string {
	if len(model) == 0 || len(s) == 0 {
		return s
	}
	newStr := ""
	for i, v := range []rune(model) {
		if len(s) > i {
			if unicode.IsUpper(v) {
				newStr += string(unicode.ToUpper([]rune(s)[i]))
			} else {
				newStr += string(s[i])
			}
		} else {
			break
		}
	}
	return newStr
}

func getWordSet() (map[int][]string, error) {
	data, err := ioutil.ReadFile("wordset.txt")
	if err != nil {
		return nil, err
	}
	wordset := strings.Fields(string(data))

	lenToWord := make(map[int][]string, len(wordset))
	for i := range lenToWord {
		lenToWord[i] = make([]string, 0, 5)
	}

	for _, v := range wordset {
		lenToWord[len(v)] = append(lenToWord[len(v)], v)
	}
	return lenToWord, nil
}

func pickRandom(s []string) string {
	return s[rand.Intn(len(s))]
}

func combineMultipleLengths(wordset map[int][]string, i int) string {
	max := 0
	for k := range wordset {
		if k > max && k <= i { // get max k such that it's under i
			max = k
		}
	}
	currInt := max
	result := ""
	for {
		if len(result) == i {
			break
		}
		if i-len(result) < currInt {
			currInt = i - len(result)
		}
		if v, ok := wordset[currInt]; ok {
			result += pickRandom(v)
			for i-len(result) >= currInt {
				result += pickRandom(v)
			}
		} else {
			currInt--
		}
	}
	return result
}

wordset.txt

a
ow
bow wow yip yap
such much woof woof woof wuff wuff bark bark rawr yelp ruff ruff bork bork
growl barky woofy borko sniff sniff
bowwow woofow yipyap yipyip yapyap
scratch
borkbork