package feed

import (
  "encoding/json"
  "fmt"
  // "strconv"
  "regexp"
  "time"
)

// partial timestamp
type Time time.Time

var timeRe = regexp.MustCompile("\\A\\d{4}-\\d{2}-\\d{2}T\\d{2}:\\d{2}Z\\z")

// Unmarshal timestamp from JSON.
func (me *Time) UnmarshalJSON(b []byte) error {
  // decode string, check for error
  var s string
  if err := json.Unmarshal(b, &s); err != nil {
    return err
  }

  // match partial string regex
  if !timeRe.MatchString(s) {
    return fmt.Errorf("invalid time: \"%s\"", s)
  }

  // correct string suffix
  s = s[0:16] + ":00Z"

  // unmarshal time
  var t time.Time
  if err := t.UnmarshalText([]byte(s)); err != nil {
    return err
  }

  // save time
  *me = Time(t)

  // return success
  return nil
}

// Marshal time.
func (me *Time) MarshalText() ([]byte, error) {
  return time.Time(*me).MarshalText()
}