package paste

import(
	"crypto/sha256"
	"fmt"
	"log"
	"os"
	"io/ioutil"
	"errors"
	"bufio"
	"strings"
)



func Store(title, date, content, dest_dir string) (string, error) {

	h := sha256.New()
	
	h.Write([]byte(title))
	h.Write([]byte(date))
	h.Write([]byte(content))

	paste := fmt.Sprintf("# Title: %s\n# Date: %s\n%s", title, date, content)
	
	paste_hash := fmt.Sprintf("%x", h.Sum(nil))
	log.Printf("  `-- hash: %s\n", paste_hash)
	paste_dir := dest_dir + "/"

	
	// Now we save the file
	for i := 0; i < len(paste_hash)-16; i++ {
		paste_name := paste_hash[i:i+16]
		if _, err := os.Stat(paste_dir + paste_name); os.IsNotExist(err) {
			// The file does not exist, so we can create it
			if err := ioutil.WriteFile(paste_dir + paste_name, []byte(paste), 0644); err == nil {
				// and then we return the URL:
				log.Printf("  `-- saving new paste to : %s", paste_dir + paste_name)
				return paste_name, nil
			} else {
				log.Printf("Cannot create the paste: %s!\n", paste_dir + paste_name)
			}
		}
	}
	return "", errors.New("Cannot store the paste...Sorry!")
}


func Retrieve(URI string) (title, date, content string, err error) {
	
	
	f_cont, err := os.Open(URI)
	defer f_cont.Close()
	
	
	if err == nil {
		stuff := bufio.NewScanner(f_cont)
		// The first line contains the title
		stuff.Scan() 
		title = strings.Trim(strings.Split(stuff.Text(), ":")[1], " ")
		stuff.Scan()
		date = strings.Trim(strings.Join(strings.Split(stuff.Text(), ":")[1:], ":"), " ")
		for stuff.Scan() {
			content  += stuff.Text() + "\n"
		}
	} else {

		return "", "", "", errors.New("Cannot retrieve paste!!!")
	}
	
	return title, date, content, nil
}