package main
import (
	"os"
	"io"
	"index/suffixarray"
	"regexp"
	"strconv"
	"log"
)

func main() {
	f, err := os.Open(os.Args[1])
	if err != nil {
		log.Fatal(err)
	}

	n, err := strconv.Atoi(os.Args[2])
	if err != nil {
		log.Fatal(err)
	}

	regexps := []*regexp.Regexp{}
	for _, re := range os.Args[3:] {
		re = "(?m:" + re + ")"
		re_compiled, err := regexp.Compile(re)
		if err != nil {
			log.Fatal(re, err)
		}

		regexps = append(regexps, re_compiled)
	}

	data := make([]byte, n)
	count, err := f.Read(data)
	if err != nil && err != io.EOF {
		log.Fatal(err)
	}
	data = data[:count]

	print("loaded ", count, " bytes; building index...")
	index := suffixarray.New(data)
	print("done.\n")
	
	for _, re_compiled := range regexps {
		for _, match := range index.FindAllIndex(re_compiled, -1) {
			print(string(data[match[0]:match[1]]), "\n")
		}
	}
}