ics - decoder.go

  // Package ics implements an encoder and decoder for iCalendar files
  package ics // import "vimagination.zapto.org/ics"
  
  import (
  	"io"
  	"strings"
  )
  
  type section interface {
  	decode(tokeniser) error
  	encode(w writer)
  	valid() error
  }
  
  // Decode decodes an iCalendar object from the given reader
  func Decode(r io.Reader) (*Calendar, error) {
  	t := newTokeniser(&unfolder{r: r})
  	if p, err := t.GetPhrase(); err != nil {
  		return nil, err
  	} else if p.Type != phraseContentLine {
  		if t.Err == io.EOF {
  			return nil, io.ErrUnexpectedEOF
  		}
  		return nil, t.Err
  	} else if strings.ToUpper(p.Data[0].Data) != "BEGIN" || strings.ToUpper(p.Data[len(p.Data)-1].Data) != "VCALENDAR" {
  		return nil, ErrInvalidCalendar
  	}
  	cal := new(Calendar)
  	if err := cal.decode(t); err != nil {
  		return nil, err
  	}
  	return cal, nil
  }