package main

import (
	"bytes"
	"encoding/json"
	"fmt"
	"log"
	"os"
	"strings"

	"github.com/Thibauth/bibtex"
)

func main() {
	fname := os.Args[1]
	f, err := os.Open(fname)
	if err != nil {
		log.Fatal(err)
	}
	db, err := bibtex.Parse(f, false)
	res, _ := json.MarshalIndent(db, "", "  ")
	fmt.Println(string(res))
}

func MarshalEntry(e bibtex.Entry) string {
	var buf bytes.Buffer
	temp := make([]string, len(e.FNames))
	open, close := "{", "}"
	if strings.Contains(e.Key, "}") {
		open, close = "(", ")"
	}
	buf.WriteString("@" + e.Type + open + e.Key + ",")
	if len(e.FNames) == 0 {
		buf.WriteString(close)
		return buf.String()
	} else {
		buf.WriteString("\n\t")
	}

	for i, field := range e.FNames {
		temp[i] = field + " = " + e.Fields[field].Marshal()
	}
	buf.WriteString(strings.Join(temp, ",\n\t"))
	buf.WriteString("\n" + close)
	return buf.String()
}

func Marshal(db *bibtex.Database) string {
	var buf bytes.Buffer
	for _, id := range db.SNames {
		buf.WriteString("@string{" + id + " = " +
			db.Strings[id].Marshal() + "}\n\n")

	}
	if db.Preamble != nil {
		buf.WriteString("@preamble{" + db.Preamble.Marshal() + "}\n\n")
	}
	res := make([]string, len(db.EKeys))
	for i, key := range db.EKeys {
		res[i] = MarshalEntry(db.Entries[key])
	}
	buf.WriteString(strings.Join(res, "\n\n"))
	return buf.String()
}