/*
 * libEtPan! -- a mail stuff library
 *
 * Copyright (C) 2001, 2002 - DINH Viet Hoa
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the libEtPan! project nor the names of its
 *    contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

/*
 * $Id$
 */

/*
  RFC 2047 : MIME (Multipurpose Internet Mail Extensions) Part Three:
             Message Header Extensions for Non-ASCII Text
*/

#include "mailmime_decode.h"

#include <ctype.h>
#include <unistd.h>
#include <sys/mman.h>
#include <string.h>
#include <stdlib.h>

#include "mailmime_content.h"

#include "charconv.h"
#include "mmapstring.h"
#include "mailimf.h"

#ifndef TRUE
#define TRUE 1
#endif

#ifndef FALSE
#define FALSE 0
#endif

static int mailmime_charset_parse(const char * message, size_t length,
				  size_t * index, char ** charset);

enum {
  MAILMIME_ENCODING_B,
  MAILMIME_ENCODING_Q
};

static int mailmime_encoding_parse(const char * message, size_t length,
				   size_t * index, int * result);

static int mailmime_etoken_parse(const char * message, size_t length,
				 size_t * index, char ** result);

static int
mailmime_non_encoded_word_parse(const char * message, size_t length,
				size_t * index,
				char ** result);

static int
mailmime_encoded_word_parse(const char * message, size_t length,
			    size_t * index,
			    struct mailmime_encoded_word ** result);
     

enum {
  TYPE_ERROR,
  TYPE_WORD,
  TYPE_ENCODED_WORD,
};

int mailmime_encoded_phrase_parse(const char * default_fromcode,
    const char * message, size_t length,
    size_t * index, const char * tocode,
    char ** result)
{
  MMAPString * gphrase;
  struct mailmime_encoded_word * word;
  int first;
  size_t cur_token;
  int r;
  int res;
  char * str;
  char * wordutf8;
  int type;
  int appendNewLine;
  cur_token = * index;

  gphrase = mmap_string_new("");
  if (gphrase == NULL) {
    res = MAILIMF_ERROR_MEMORY;
    goto err;
  }

  first = TRUE;

  type = TYPE_ERROR; /* XXX - removes a gcc warning */
  /* LUTZ add*/
  appendNewLine = FALSE;
  while (1) { 

      r = mailmime_encoded_word_parse(message, length, &cur_token, &word);
      if (r == MAILIMF_NO_ERROR) {
          if (!first) {
              if (type != TYPE_ENCODED_WORD) {
                  if (mmap_string_append_c(gphrase, ' ') == NULL) {
                      mailmime_encoded_word_free(word);
                      res = MAILIMF_ERROR_MEMORY;
                      goto free;
                  }
              }
          }
          type = TYPE_ENCODED_WORD;
          wordutf8 = NULL;
          r = charconv(tocode, word->wd_charset, word->wd_text,
                       strlen(word->wd_text), &wordutf8);
          switch (r) {
          case MAIL_CHARCONV_ERROR_MEMORY:
              mailmime_encoded_word_free(word);
              res = MAILIMF_ERROR_MEMORY;
              goto free;

          case MAIL_CHARCONV_ERROR_UNKNOWN_CHARSET:
          case MAIL_CHARCONV_ERROR_CONV:
              mailmime_encoded_word_free(word);
              res = MAILIMF_ERROR_PARSE;
              goto free;
          }
      
          if (wordutf8 != NULL) {
              if (mmap_string_append(gphrase, wordutf8) == NULL) {
                  mailmime_encoded_word_free(word);
                  free(wordutf8);
                  res = MAILIMF_ERROR_MEMORY;
                  goto free;
              }
              free(wordutf8);
          }
          mailmime_encoded_word_free(word);
          first = FALSE;
      }
      else if (r == MAILIMF_ERROR_PARSE) {
          /* do nothing */
      }
      else {
          res = r;
          goto free;
      }

      if (r == MAILIMF_ERROR_PARSE) {
          char * raw_word;

          r = mailmime_non_encoded_word_parse(message, length,
                                              &cur_token, &raw_word);
          if (r == MAILIMF_NO_ERROR) {
              if (!first) {
                  if (mmap_string_append_c(gphrase, ' ') == NULL) {
                      free(raw_word);
                      res = MAILIMF_ERROR_MEMORY;
                      goto free;
                  }
              }
              type = TYPE_WORD;
        
              wordutf8 = NULL;
              r = charconv(tocode, default_fromcode, raw_word,
                           strlen(raw_word), &wordutf8);
        
              switch (r) {
              case MAIL_CHARCONV_ERROR_MEMORY:
                  free(raw_word);
                  res = MAILIMF_ERROR_MEMORY;
                  goto free;
          
              case MAIL_CHARCONV_ERROR_UNKNOWN_CHARSET:
              case MAIL_CHARCONV_ERROR_CONV:
                  free(raw_word);
                  res = MAILIMF_ERROR_PARSE;
                  goto free;
              }
              // LUTZ add
              if ( appendNewLine ) {
                  appendNewLine = FALSE;
              if (mmap_string_append(gphrase, "\n") == NULL) {
                  free(wordutf8);
                  free(raw_word);
                  res = MAILIMF_ERROR_MEMORY;
                  goto free;
              }
              }
              //fprintf(stderr,"append *%s*  \n",wordutf8 );
              if (mmap_string_append(gphrase, wordutf8) == NULL) {
                  free(wordutf8);
                  free(raw_word);
                  res = MAILIMF_ERROR_MEMORY;
                  goto free;
              }
              // LUTZ fix
              free(wordutf8);
              free(raw_word);
              first = FALSE;
          }
          else if (r == MAILIMF_ERROR_PARSE) {
              // LUTZ add
              if ( cur_token >= length )
                  break;
              ++cur_token;
              appendNewLine = TRUE;
          }
          else {
              res = r;
              goto free;
          }
      }
  }

  if (first) {
    res = MAILIMF_ERROR_PARSE;
    goto free;
  }

  str = strdup(gphrase->str);
  if (str == NULL) {
    res = MAILIMF_ERROR_MEMORY;
    goto free;
  }
  mmap_string_free(gphrase);

  * result = str;
  * index = cur_token;

  return MAILIMF_NO_ERROR;

 free:
  mmap_string_free(gphrase);
 err:
  return res;
}

static int
mailmime_non_encoded_word_parse(const char * message, size_t length,
				size_t * index,
				char ** result)
{
  int end;
  size_t cur_token;
  int res;
  char * text;
  int r;
  size_t begin;

  cur_token = * index;

  r = mailimf_fws_parse(message, length, &cur_token);
  if ((r != MAILIMF_NO_ERROR) && (r != MAILIMF_ERROR_PARSE)) {
    res = r;
    goto err;
  }

  begin = cur_token;

  end = FALSE;
  while (1) {
    if (cur_token >= length)
      break;

    switch (message[cur_token]) {
      case ' ':
      case '\t':
      case '\r':
      case '\n':
	end = TRUE;
	break;
    }

    if (end)
      break;

    cur_token ++;
  }

  if (cur_token - begin == 0) {
      res = MAILIMF_ERROR_PARSE;
      goto err;
  }

  text = malloc(cur_token - begin + 1);
  if (text == NULL) {
    res = MAILIMF_ERROR_MEMORY;
    goto err;
  }

  memcpy(text, message + begin, cur_token - begin);
  text[cur_token - begin] = '\0';

  * index = cur_token;
  * result = text;

  return MAILIMF_NO_ERROR;

 err:
  return res;
}

static int mailmime_encoded_word_parse(const char * message, size_t length,
				       size_t * index,
				       struct mailmime_encoded_word ** result)
{
  size_t cur_token;
  char * charset;
  int encoding;
  char * text;
  size_t end_encoding;
  char * decoded;
  size_t decoded_len;
  struct mailmime_encoded_word * ew;
  int r;
  int res;
  int opening_quote;
  int end;

  cur_token = * index;

  r = mailimf_fws_parse(message, length, &cur_token);
  if ((r != MAILIMF_NO_ERROR) && (r != MAILIMF_ERROR_PARSE)) {
    res = r;
    goto err;
  }

  opening_quote = FALSE;
  r = mailimf_char_parse(message, length, &cur_token, '\"');
  if (r == MAILIMF_NO_ERROR) {
    opening_quote = TRUE;
  }
  else if (r == MAILIMF_ERROR_PARSE) {
    /* do nothing */  
  }
  else {
    res = r;
    goto err;
  }

  r = mailimf_token_case_insensitive_parse(message, length, &cur_token, "=?");
  if (r != MAILIMF_NO_ERROR) {
    res = r;
    goto err;
  }

  r = mailmime_charset_parse(message, length, &cur_token, &charset);
  if (r != MAILIMF_NO_ERROR) {
    res = r;
    goto err;
  }

  r = mailimf_char_parse(message, length, &cur_token, '?');
  if (r != MAILIMF_NO_ERROR) {
    res = r;
    goto free_charset;
  }

  r = mailmime_encoding_parse(message, length, &cur_token, &encoding);
  if (r != MAILIMF_NO_ERROR) {
    res = r;
    goto free_charset;
  }

  r = mailimf_char_parse(message, length, &cur_token, '?');
  if (r != MAILIMF_NO_ERROR) {
    res = r;
    goto free_charset;
  }

  end = FALSE;
  end_encoding = cur_token;
  while (1) {
    if (end_encoding >= length)
      break;

    switch (message[end_encoding]) {
      case '?':
#if 0
      case ' ':
#endif
	end = TRUE;
	break;
    }

    if (end)
      break;

    end_encoding ++;
  }

  decoded_len = 0;
  decoded = NULL;
  switch (encoding) {
  case MAILMIME_ENCODING_B:
    r = mailmime_base64_body_parse(message, end_encoding,
				   &cur_token, &decoded,
				   &decoded_len);
      
    if (r != MAILIMF_NO_ERROR) {
      res = r;
      goto free_charset;
    }
    break;
  case MAILMIME_ENCODING_Q:
    r = mailmime_quoted_printable_body_parse(message, end_encoding,
					     &cur_token, &decoded,
					     &decoded_len, TRUE);

    if (r != MAILIMF_NO_ERROR) {
      res = r;
      goto free_charset;
    }

    break;
  }

  text = malloc(decoded_len + 1);
  if (text == NULL) {
    res = MAILIMF_ERROR_MEMORY;
    goto free_charset;
  }

  if (decoded_len > 0)
    memcpy(text, decoded, decoded_len);
  text[decoded_len] = '\0';

  mailmime_decoded_part_free(decoded);

  r = mailimf_token_case_insensitive_parse(message, length, &cur_token, "?=");
  if (r != MAILIMF_NO_ERROR) {
    res = r;
    goto free_encoded_text;
  }

  if (opening_quote) {
    r = mailimf_char_parse(message, length, &cur_token, '\"');
    if ((r != MAILIMF_NO_ERROR) && (r != MAILIMF_ERROR_PARSE)) {
      res = r;
      goto free_encoded_text;
    }
  }

  ew = mailmime_encoded_word_new(charset, text);
  if (ew == NULL) {
    res = MAILIMF_ERROR_MEMORY;
    goto free_encoded_text;
  }

  * result = ew;
  * index = cur_token;
  
  return MAILIMF_NO_ERROR;

 free_encoded_text:
  mailmime_encoded_text_free(text);
 free_charset:
  mailmime_charset_free(charset);
 err:
  return res;
}

static int mailmime_charset_parse(const char * message, size_t length,
				  size_t * index, char ** charset)
{
  return mailmime_etoken_parse(message, length, index, charset);
}

static int mailmime_encoding_parse(const char * message, size_t length,
				   size_t * index, int * result)
{
  size_t cur_token;
  int encoding;

  cur_token = * index;

  if (cur_token >= length)
    return MAILIMF_ERROR_PARSE;

  switch ((char) toupper((unsigned char) message[cur_token])) {
  case 'Q':
    encoding = MAILMIME_ENCODING_Q;
    break;
  case 'B':
    encoding = MAILMIME_ENCODING_B;
    break;
  default:
    return MAILIMF_ERROR_INVAL;
  }

  cur_token ++;

  * result = encoding;
  * index = cur_token;

  return MAILIMF_NO_ERROR;
}

int is_etoken_char(char ch)
{
  unsigned char uch = ch;

  if (uch < 31)
    return FALSE;

  switch (uch) {
  case ' ':
  case '(':
  case ')':
  case '<':
  case '>':
  case '@':
  case ',':
  case ';':
  case ':':
  case '"':
  case '/':
  case '[':
  case ']':
  case '?':
  case '.':
  case '=':
    return FALSE;
  }

  return TRUE;
}

static int mailmime_etoken_parse(const char * message, size_t length,
				 size_t * index, char ** result)
{
  return mailimf_custom_string_parse(message, length,
				     index, result,
				     is_etoken_char);
}