/*
 * Copyright notice from original mutt:
 * Copyright (C) 1996-2000 Michael R. Elkins <me@mutt.org>
 *
 * This file is part of mutt-ng, see http://www.muttng.org/.
 * It's licensed under the GNU General Public License,
 * please see the file GPL in the top level source directory.
 */

#if HAVE_CONFIG_H
# include "config.h"
#endif

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

#include "mutt.h"
#include "ascii.h"
#include "recvattach.h"
#include "handler.h"
#include "mutt_curses.h"
#include "rfc1524.h"
#include "rfc3676.h"
#include "keymap.h"
#include "mime.h"
#include "copy.h"
#include "charset.h"
#include "mutt_crypt.h"
#include "state.h"
#include "attach.h"
#include "lib.h"

#include "lib/mem.h"
#include "lib/intl.h"
#include "lib/str.h"
#include "lib/debug.h"

typedef int handler_f (BODY *, STATE *);
typedef handler_f *handler_t;

int Index_hex[128] = {
  -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
  -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
  -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
  0, 1, 2, 3, 4, 5, 6, 7, 8, 9, -1, -1, -1, -1, -1, -1,
  -1, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1,
  -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
  -1, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1,
  -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1
};

int Index_64[128] = {
  -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
  -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
  -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 62, -1, -1, -1, 63,
  52, 53, 54, 55, 56, 57, 58, 59, 60, 61, -1, -1, -1, -1, -1, -1,
  -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14,
  15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, -1, -1, -1, -1, -1,
  -1, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,
  41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, -1, -1, -1, -1, -1
};

void mutt_decode_xbit (STATE * s, long len, int istext, iconv_t cd)
{
  int c, ch;
  char bufi[BUFI_SIZE];
  size_t l = 0;

  if (istext) {
    state_set_prefix (s);

    while ((c = fgetc (s->fpin)) != EOF && len--) {
      if (c == '\r' && len) {
        if ((ch = fgetc (s->fpin)) == '\n') {
          c = ch;
          len--;
        }
        else
          ungetc (ch, s->fpin);
      }

      bufi[l++] = c;
      if (l == sizeof (bufi))
        mutt_convert_to_state (cd, bufi, &l, s);
    }

    mutt_convert_to_state (cd, bufi, &l, s);
    mutt_convert_to_state (cd, 0, 0, s);

    state_reset_prefix (s);
  }
  else
    mutt_copy_bytes (s->fpin, s->fpout, len);
}

static int qp_decode_triple (char *s, char *d)
{
  /* soft line break */
  if (*s == '=' && !(*(s + 1)))
    return 1;

  /* quoted-printable triple */
  if (*s == '=' &&
      isxdigit ((unsigned char) *(s + 1)) &&
      isxdigit ((unsigned char) *(s + 2))) {
    *d = (hexval (*(s + 1)) << 4) | hexval (*(s + 2));
    return 0;
  }

  /* something else */
  return -1;
}

static void qp_decode_line (char *dest, char *src, size_t * l, int last)
{
  char *d, *s;
  char c;

  int kind;
  int soft = 0;

  /* decode the line */

  for (d = dest, s = src; *s;) {
    switch ((kind = qp_decode_triple (s, &c))) {
    case 0:
      *d++ = c;
      s += 3;
      break;                    /* qp triple */
    case -1:
      *d++ = *s++;
      break;                    /* single character */
    case 1:
      soft = 1;
      s++;
      break;                    /* soft line break */
    }
  }

  if (!soft && last == '\n')
    *d++ = '\n';

  *d = '\0';
  *l = d - dest;
}

/* 
 * Decode an attachment encoded with quoted-printable.
 * 
 * Why doesn't this overflow any buffers?  First, it's guaranteed
 * that the length of a line grows when you _en_-code it to
 * quoted-printable.  That means that we always can store the
 * result in a buffer of at most the _same_ size.
 * 
 * Now, we don't special-case if the line we read with fgets()
 * isn't terminated.  We don't care about this, since STRING > 78,
 * so corrupted input will just be corrupted a bit more.  That
 * implies that STRING+1 bytes are always sufficient to store the
 * result of qp_decode_line.
 * 
 * Finally, at soft line breaks, some part of a multibyte character
 * may have been left over by mutt_convert_to_state().  This shouldn't
 * be more than 6 characters, so STRING + 7 should be sufficient
 * memory to store the decoded data.
 * 
 * Just to make sure that I didn't make some off-by-one error
 * above, we just use STRING*2 for the target buffer's size.
 * 
 */

void mutt_decode_quoted (STATE * s, long len, int istext, iconv_t cd)
{
  char line[STRING];
  char decline[2 * STRING];
  size_t l = 0;
  size_t linelen;               /* number of input bytes in `line' */
  size_t l3;

  int last;                     /* store the last character in the input line */

  if (istext)
    state_set_prefix (s);

  while (len > 0) {
    last = 0;

    /*
     * It's ok to use a fixed size buffer for input, even if the line turns
     * out to be longer than this.  Just process the line in chunks.  This
     * really shouldn't happen according the MIME spec, since Q-P encoded
     * lines are at most 76 characters, but we should be liberal about what
     * we accept.
     */
    if (fgets (line, MIN ((ssize_t) sizeof (line), len + 1), s->fpin) == NULL)
      break;

    linelen = str_len (line);
    len -= linelen;

    /*
     * inspect the last character we read so we can tell if we got the
     * entire line.
     */
    last = linelen ? line[linelen - 1] : 0;

    /* chop trailing whitespace if we got the full line */
    if (last == '\n') {
      while (linelen > 0 && ISSPACE (line[linelen - 1]))
        linelen--;
      line[linelen] = 0;
    }

    /* decode and do character set conversion */
    qp_decode_line (decline + l, line, &l3, last);
    l += l3;
    mutt_convert_to_state (cd, decline, &l, s);
  }

  mutt_convert_to_state (cd, 0, 0, s);
  state_reset_prefix (s);
}

void mutt_decode_base64 (STATE * s, long len, int istext, iconv_t cd)
{
  char buf[5];
  int c1, c2, c3, c4, ch, cr = 0, i;
  char bufi[BUFI_SIZE];
  size_t l = 0;

  buf[4] = 0;

  if (istext)
    state_set_prefix (s);

  while (len > 0) {
    for (i = 0; i < 4 && len > 0; len--) {
      if ((ch = fgetc (s->fpin)) == EOF)
        break;
      if (ch >= 0 && ch < 128 && (base64val (ch) != -1 || ch == '='))
        buf[i++] = ch;
    }
    if (i != 4) {
      debug_print (2, ("didn't get a multiple of 4 chars.\n"));
      break;
    }

    c1 = base64val (buf[0]);
    c2 = base64val (buf[1]);
    ch = (c1 << 2) | (c2 >> 4);

    if (cr && ch != '\n')
      bufi[l++] = '\r';

    cr = 0;

    if (istext && ch == '\r')
      cr = 1;
    else
      bufi[l++] = ch;

    if (buf[2] == '=')
      break;
    c3 = base64val (buf[2]);
    ch = ((c2 & 0xf) << 4) | (c3 >> 2);

    if (cr && ch != '\n')
      bufi[l++] = '\r';

    cr = 0;

    if (istext && ch == '\r')
      cr = 1;
    else
      bufi[l++] = ch;

    if (buf[3] == '=')
      break;
    c4 = base64val (buf[3]);
    ch = ((c3 & 0x3) << 6) | c4;

    if (cr && ch != '\n')
      bufi[l++] = '\r';
    cr = 0;

    if (istext && ch == '\r')
      cr = 1;
    else
      bufi[l++] = ch;

    if (l + 8 >= sizeof (bufi))
      mutt_convert_to_state (cd, bufi, &l, s);
  }

  if (cr)
    bufi[l++] = '\r';

  mutt_convert_to_state (cd, bufi, &l, s);
  mutt_convert_to_state (cd, 0, 0, s);

  state_reset_prefix (s);
}

unsigned char decode_byte (char ch)
{
  if (ch == 96)
    return 0;
  return ch - 32;
}

void mutt_decode_uuencoded (STATE * s, long len, int istext, iconv_t cd)
{
  char tmps[SHORT_STRING];
  char linelen, c, l, out;
  char *pt;
  char bufi[BUFI_SIZE];
  size_t k = 0;

  if (istext)
    state_set_prefix (s);

  while (len > 0) {
    if ((fgets (tmps, sizeof (tmps), s->fpin)) == NULL)
      return;
    len -= str_len (tmps);
    if ((!str_ncmp (tmps, "begin", 5)) && ISSPACE (tmps[5]))
      break;
  }
  while (len > 0) {
    if ((fgets (tmps, sizeof (tmps), s->fpin)) == NULL)
      return;
    len -= str_len (tmps);
    if (!str_ncmp (tmps, "end", 3))
      break;
    pt = tmps;
    linelen = decode_byte (*pt);
    pt++;
    for (c = 0; c < linelen;) {
      for (l = 2; l <= 6; l += 2) {
        out = decode_byte (*pt) << l;
        pt++;
        out |= (decode_byte (*pt) >> (6 - l));
        bufi[k++] = out;
        c++;
        if (c == linelen)
          break;
      }
      mutt_convert_to_state (cd, bufi, &k, s);
      pt++;
    }
  }

  mutt_convert_to_state (cd, bufi, &k, s);
  mutt_convert_to_state (cd, 0, 0, s);

  state_reset_prefix (s);
}

/* ----------------------------------------------------------------------------
 * A (not so) minimal implementation of RFC1563.
 */

#define IndentSize (4)

enum { RICH_PARAM = 0, RICH_BOLD, RICH_UNDERLINE, RICH_ITALIC, RICH_NOFILL,
  RICH_INDENT, RICH_INDENT_RIGHT, RICH_EXCERPT, RICH_CENTER, RICH_FLUSHLEFT,
  RICH_FLUSHRIGHT, RICH_COLOR, RICH_LAST_TAG
};

static struct {
  const char *tag_name;
  int index;
} EnrichedTags[] = {
  {
  "param", RICH_PARAM}, {
  "bold", RICH_BOLD}, {
  "italic", RICH_ITALIC}, {
  "underline", RICH_UNDERLINE}, {
  "nofill", RICH_NOFILL}, {
  "excerpt", RICH_EXCERPT}, {
  "indent", RICH_INDENT}, {
  "indentright", RICH_INDENT_RIGHT}, {
  "center", RICH_CENTER}, {
  "flushleft", RICH_FLUSHLEFT}, {
  "flushright", RICH_FLUSHRIGHT}, {
  "flushboth", RICH_FLUSHLEFT}, {
  "color", RICH_COLOR}, {
  "x-color", RICH_COLOR}, {
  NULL, -1}
};

struct enriched_state {
  char *buffer;
  char *line;
  char *param;
  size_t buff_len;
  size_t line_len;
  size_t line_used;
  size_t line_max;
  size_t indent_len;
  size_t word_len;
  size_t buff_used;
  size_t param_used;
  size_t param_len;
  int tag_level[RICH_LAST_TAG];
  int WrapMargin;
  STATE *s;
};

static void enriched_wrap (struct enriched_state *stte)
{
  int x;
  int extra;

  if (stte->line_len) {
    if (stte->tag_level[RICH_CENTER] || stte->tag_level[RICH_FLUSHRIGHT]) {
      /* Strip trailing white space */
      size_t y = stte->line_used - 1;

      while (y && ISSPACE (stte->line[y])) {
        stte->line[y] = '\0';
        y--;
        stte->line_used--;
        stte->line_len--;
      }
      if (stte->tag_level[RICH_CENTER]) {
        /* Strip leading whitespace */
        y = 0;

        while (stte->line[y] && ISSPACE (stte->line[y]))
          y++;
        if (y) {
          size_t z;

          for (z = y; z <= stte->line_used; z++) {
            stte->line[z - y] = stte->line[z];
          }

          stte->line_len -= y;
          stte->line_used -= y;
        }
      }
    }

    extra = stte->WrapMargin - stte->line_len - stte->indent_len -
      (stte->tag_level[RICH_INDENT_RIGHT] * IndentSize);
    if (extra > 0) {
      if (stte->tag_level[RICH_CENTER]) {
        x = extra / 2;
        while (x) {
          state_putc (' ', stte->s);
          x--;
        }
      }
      else if (stte->tag_level[RICH_FLUSHRIGHT]) {
        x = extra - 1;
        while (x) {
          state_putc (' ', stte->s);
          x--;
        }
      }
    }
    state_puts (stte->line, stte->s);
  }

  state_putc ('\n', stte->s);
  stte->line[0] = '\0';
  stte->line_len = 0;
  stte->line_used = 0;
  stte->indent_len = 0;
  if (stte->s->prefix) {
    state_puts (stte->s->prefix, stte->s);
    stte->indent_len += str_len (stte->s->prefix);
  }

  if (stte->tag_level[RICH_EXCERPT]) {
    x = stte->tag_level[RICH_EXCERPT];
    while (x) {
      if (stte->s->prefix) {
        state_puts (stte->s->prefix, stte->s);
        stte->indent_len += str_len (stte->s->prefix);
      }
      else {
        state_puts ("> ", stte->s);
        stte->indent_len += str_len ("> ");
      }
      x--;
    }
  }
  else
    stte->indent_len = 0;
  if (stte->tag_level[RICH_INDENT]) {
    x = stte->tag_level[RICH_INDENT] * IndentSize;
    stte->indent_len += x;
    while (x) {
      state_putc (' ', stte->s);
      x--;
    }
  }
}

static void enriched_flush (struct enriched_state *stte, int wrap)
{
  if (!stte->tag_level[RICH_NOFILL] && (stte->line_len + stte->word_len >
                                        (stte->WrapMargin -
                                         (stte->tag_level[RICH_INDENT_RIGHT] *
                                          IndentSize) - stte->indent_len)))
    enriched_wrap (stte);

  if (stte->buff_used) {
    stte->buffer[stte->buff_used] = '\0';
    stte->line_used += stte->buff_used;
    if (stte->line_used > stte->line_max) {
      stte->line_max = stte->line_used;
      mem_realloc (&stte->line, stte->line_max + 1);
    }
    strcat (stte->line, stte->buffer);  /* __STRCAT_CHECKED__ */
    stte->line_len += stte->word_len;
    stte->word_len = 0;
    stte->buff_used = 0;
  }
  if (wrap)
    enriched_wrap (stte);
}


static void enriched_putc (int c, struct enriched_state *stte)
{
  if (stte->tag_level[RICH_PARAM]) {
    if (stte->tag_level[RICH_COLOR]) {
      if (stte->param_used + 1 >= stte->param_len)
        mem_realloc (&stte->param, (stte->param_len += STRING));

      stte->param[stte->param_used++] = c;
    }
    return;                     /* nothing to do */
  }

  /* see if more space is needed (plus extra for possible rich characters) */
  if (stte->buff_len < stte->buff_used + 3) {
    stte->buff_len += LONG_STRING;
    mem_realloc (&stte->buffer, stte->buff_len + 1);
  }

  if ((!stte->tag_level[RICH_NOFILL] && ISSPACE (c)) || c == '\0') {
    if (c == '\t')
      stte->word_len += 8 - (stte->line_len + stte->word_len) % 8;
    else
      stte->word_len++;

    stte->buffer[stte->buff_used++] = c;
    enriched_flush (stte, 0);
  }
  else {
    if (stte->s->flags & M_DISPLAY) {
      if (stte->tag_level[RICH_BOLD]) {
        stte->buffer[stte->buff_used++] = c;
        stte->buffer[stte->buff_used++] = '\010';
        stte->buffer[stte->buff_used++] = c;
      }
      else if (stte->tag_level[RICH_UNDERLINE]) {

        stte->buffer[stte->buff_used++] = '_';
        stte->buffer[stte->buff_used++] = '\010';
        stte->buffer[stte->buff_used++] = c;
      }
      else if (stte->tag_level[RICH_ITALIC]) {
        stte->buffer[stte->buff_used++] = c;
        stte->buffer[stte->buff_used++] = '\010';
        stte->buffer[stte->buff_used++] = '_';
      }
      else {
        stte->buffer[stte->buff_used++] = c;
      }
    }
    else {
      stte->buffer[stte->buff_used++] = c;
    }
    stte->word_len++;
  }
}

static void enriched_puts (char *s, struct enriched_state *stte)
{
  char *c;

  if (stte->buff_len < stte->buff_used + str_len (s)) {
    stte->buff_len += LONG_STRING;
    mem_realloc (&stte->buffer, stte->buff_len + 1);
  }
  c = s;
  while (*c) {
    stte->buffer[stte->buff_used++] = *c;
    c++;
  }
}

static void enriched_set_flags (const char *tag, struct enriched_state *stte)
{
  const char *tagptr = tag;
  int i, j;

  if (*tagptr == '/')
    tagptr++;

  for (i = 0, j = -1; EnrichedTags[i].tag_name; i++)
    if (ascii_strcasecmp (EnrichedTags[i].tag_name, tagptr) == 0) {
      j = EnrichedTags[i].index;
      break;
    }

  if (j != -1) {
    if (j == RICH_CENTER || j == RICH_FLUSHLEFT || j == RICH_FLUSHRIGHT)
      enriched_flush (stte, 1);

    if (*tag == '/') {
      if (stte->tag_level[j])   /* make sure not to go negative */
        stte->tag_level[j]--;
      if ((stte->s->flags & M_DISPLAY) && j == RICH_PARAM
          && stte->tag_level[RICH_COLOR]) {
        stte->param[stte->param_used] = '\0';
        if (!ascii_strcasecmp (stte->param, "black")) {
          enriched_puts ("\033[30m", stte);
        }
        else if (!ascii_strcasecmp (stte->param, "red")) {
          enriched_puts ("\033[31m", stte);
        }
        else if (!ascii_strcasecmp (stte->param, "green")) {
          enriched_puts ("\033[32m", stte);
        }
        else if (!ascii_strcasecmp (stte->param, "yellow")) {
          enriched_puts ("\033[33m", stte);
        }
        else if (!ascii_strcasecmp (stte->param, "blue")) {
          enriched_puts ("\033[34m", stte);
        }
        else if (!ascii_strcasecmp (stte->param, "magenta")) {
          enriched_puts ("\033[35m", stte);
        }
        else if (!ascii_strcasecmp (stte->param, "cyan")) {
          enriched_puts ("\033[36m", stte);
        }
        else if (!ascii_strcasecmp (stte->param, "white")) {
          enriched_puts ("\033[37m", stte);
        }
      }
      if ((stte->s->flags & M_DISPLAY) && j == RICH_COLOR) {
        enriched_puts ("\033[0m", stte);
      }

      /* flush parameter buffer when closing the tag */
      if (j == RICH_PARAM) {
        stte->param_used = 0;
        stte->param[0] = '\0';
      }
    }
    else
      stte->tag_level[j]++;

    if (j == RICH_EXCERPT)
      enriched_flush (stte, 1);
  }
}

int text_enriched_handler (BODY * a, STATE * s)
{
  enum {
    TEXT, LANGLE, TAG, BOGUS_TAG, NEWLINE, ST_EOF, DONE
  } state = TEXT;

  long bytes = a->length;
  struct enriched_state stte;
  int c = 0;
  int tag_len = 0;
  char tag[LONG_STRING + 1];

  memset (&stte, 0, sizeof (stte));
  stte.s = s;
  stte.WrapMargin =
    ((s->flags & M_DISPLAY) ? (COLS - 4) : ((COLS - 4) <
                                            72) ? (COLS - 4) : 72);
  stte.line_max = stte.WrapMargin * 4;
  stte.line = (char *) mem_calloc (1, stte.line_max + 1);
  stte.param = (char *) mem_calloc (1, STRING);

  stte.param_len = STRING;
  stte.param_used = 0;

  if (s->prefix) {
    state_puts (s->prefix, s);
    stte.indent_len += str_len (s->prefix);
  }

  while (state != DONE) {
    if (state != ST_EOF) {
      if (!bytes || (c = fgetc (s->fpin)) == EOF)
        state = ST_EOF;
      else
        bytes--;
    }

    switch (state) {
    case TEXT:
      switch (c) {
      case '<':
        state = LANGLE;
        break;

      case '\n':
        if (stte.tag_level[RICH_NOFILL]) {
          enriched_flush (&stte, 1);
        }
        else {
          enriched_putc (' ', &stte);
          state = NEWLINE;
        }
        break;

      default:
        enriched_putc (c, &stte);
      }
      break;

    case LANGLE:
      if (c == '<') {
        enriched_putc (c, &stte);
        state = TEXT;
        break;
      }
      else {
        tag_len = 0;
        state = TAG;
      }
      /* Yes, fall through (it wasn't a <<, so this char is first in TAG) */
    case TAG:
      if (c == '>') {
        tag[tag_len] = '\0';
        enriched_set_flags (tag, &stte);
        state = TEXT;
      }
      else if (tag_len < LONG_STRING)   /* ignore overly long tags */
        tag[tag_len++] = c;
      else
        state = BOGUS_TAG;
      break;

    case BOGUS_TAG:
      if (c == '>')
        state = TEXT;
      break;

    case NEWLINE:
      if (c == '\n')
        enriched_flush (&stte, 1);
      else {
        ungetc (c, s->fpin);
        bytes++;
        state = TEXT;
      }
      break;

    case ST_EOF:
      enriched_putc ('\0', &stte);
      enriched_flush (&stte, 1);
      state = DONE;
      break;

    case DONE:                 /* not reached, but gcc complains if this is absent */
      break;
    }
  }

  state_putc ('\n', s);         /* add a final newline */

  mem_free (&(stte.buffer));
  mem_free (&(stte.line));
  mem_free (&(stte.param));

  return (0);
}

#define TXTHTML     1
#define TXTPLAIN    2
#define TXTENRICHED 3

static int alternative_handler (BODY * a, STATE * s)
{
  BODY *choice = NULL;
  BODY *b;
  LIST *t;
  char buf[STRING];
  int type = 0;
  int mustfree = 0;
  int rc = 0;

  if (a->encoding == ENCBASE64 || a->encoding == ENCQUOTEDPRINTABLE ||
      a->encoding == ENCUUENCODED) {
    struct stat st;

    mustfree = 1;
    fstat (fileno (s->fpin), &st);
    b = mutt_new_body ();
    b->length = (long) st.st_size;
    b->parts = mutt_parse_multipart (s->fpin,
                                     mutt_get_parameter ("boundary",
                                                         a->parameter),
                                     (long) st.st_size,
                                     ascii_strcasecmp ("digest",
                                                       a->subtype) == 0);
  }
  else
    b = a;

  a = b;

  /* First, search list of prefered types */
  t = AlternativeOrderList;
  while (t && !choice) {
    char *c;
    int btlen;                  /* length of basetype */
    int wild;                   /* do we have a wildcard to match all subtypes? */

    c = strchr (t->data, '/');
    if (c) {
      wild = (c[1] == '*' && c[2] == 0);
      btlen = c - t->data;
    }
    else {
      wild = 1;
      btlen = str_len (t->data);
    }

    if (a && a->parts)
      b = a->parts;
    else
      b = a;
    while (b) {
      const char *bt = TYPE (b);

      if (!ascii_strncasecmp (bt, t->data, btlen) && bt[btlen] == 0) {
        /* the basetype matches */
        if (wild || !ascii_strcasecmp (t->data + btlen + 1, b->subtype)) {
          choice = b;
        }
      }
      b = b->next;
    }
    t = t->next;
  }

  /* Next, look for an autoviewable type */
  if (!choice) {
    if (a && a->parts)
      b = a->parts;
    else
      b = a;
    while (b) {
      snprintf (buf, sizeof (buf), "%s/%s", TYPE (b), b->subtype);
      if (mutt_is_autoview (b, buf)) {
        rfc1524_entry *entry = rfc1524_new_entry ();

        if (rfc1524_mailcap_lookup (b, buf, entry, M_AUTOVIEW)) {
          choice = b;
        }
        rfc1524_free_entry (&entry);
      }
      b = b->next;
    }
  }

  /* Then, look for a text entry */
  if (!choice) {
    if (a && a->parts)
      b = a->parts;
    else
      b = a;
    while (b) {
      if (b->type == TYPETEXT) {
        if (!ascii_strcasecmp ("plain", b->subtype) && type <= TXTPLAIN) {
          choice = b;
          type = TXTPLAIN;
        }
        else if (!ascii_strcasecmp ("enriched", b->subtype)
                 && type <= TXTENRICHED) {
          choice = b;
          type = TXTENRICHED;
        }
        else if (!ascii_strcasecmp ("html", b->subtype) && type <= TXTHTML) {
          choice = b;
          type = TXTHTML;
        }
      }
      b = b->next;
    }
  }

  /* Finally, look for other possibilities */
  if (!choice) {
    if (a && a->parts)
      b = a->parts;
    else
      b = a;
    while (b) {
      if (mutt_can_decode (b))
        choice = b;
      b = b->next;
    }
  }

  if (choice) {
    if (s->flags & M_DISPLAY && !option (OPTWEED)) {
      fseeko (s->fpin, choice->hdr_offset, 0);
      mutt_copy_bytes (s->fpin, s->fpout,
                       choice->offset - choice->hdr_offset);
    }
    mutt_body_handler (choice, s);
  }
  else if (s->flags & M_DISPLAY) {
    /* didn't find anything that we could display! */
    state_mark_attach (s);
    state_puts (_("[-- Error:  Could not display any parts of Multipart/Alternative! --]\n"), s);
    rc = -1;
  }

  if (mustfree)
    mutt_free_body (&a);

  return (rc);
}

/* handles message/rfc822 body parts */
static int message_handler (BODY * a, STATE * s)
{
  struct stat st;
  BODY *b;
  LOFF_T off_start;
  int rc = 0;

  off_start = ftello (s->fpin);
  if (a->encoding == ENCBASE64 || a->encoding == ENCQUOTEDPRINTABLE ||
      a->encoding == ENCUUENCODED) {
    fstat (fileno (s->fpin), &st);
    b = mutt_new_body ();
    b->length = (long) st.st_size;
    b->parts = mutt_parse_messageRFC822 (s->fpin, b);
  }
  else
    b = a;

  if (b->parts) {
    mutt_copy_hdr (s->fpin, s->fpout, off_start, b->parts->offset,
                   (((s->flags & M_WEED)
                     || ((s->flags & (M_DISPLAY | M_PRINTING))
                         && option (OPTWEED))) ? (CH_WEED | CH_REORDER) : 0) |
                   (s->prefix ? CH_PREFIX : 0) | CH_DECODE | CH_FROM,
                   s->prefix);

    if (s->prefix)
      state_puts (s->prefix, s);
    state_putc ('\n', s);

    rc = mutt_body_handler (b->parts, s);
  }

  if (a->encoding == ENCBASE64 || a->encoding == ENCQUOTEDPRINTABLE ||
      a->encoding == ENCUUENCODED)
    mutt_free_body (&b);

  return (rc);
}

/* returns 1 if decoding the attachment will produce output */
int mutt_can_decode (BODY * a)
{
  char type[STRING];

  snprintf (type, sizeof (type), "%s/%s", TYPE (a), a->subtype);
  if (mutt_is_autoview (a, type))
    return (rfc1524_mailcap_lookup (a, type, NULL, M_AUTOVIEW));
  else if (a->type == TYPETEXT)
    return (1);
  else if (a->type == TYPEMESSAGE)
    return (1);
  else if (a->type == TYPEMULTIPART) {
    BODY *p;

    if (WithCrypto) {
      if (ascii_strcasecmp (a->subtype, "signed") == 0 ||
          ascii_strcasecmp (a->subtype, "encrypted") == 0)
        return (1);
    }

    for (p = a->parts; p; p = p->next) {
      if (mutt_can_decode (p))
        return (1);
    }

  }
  else if (WithCrypto && a->type == TYPEAPPLICATION) {
    if ((WithCrypto & APPLICATION_PGP) && mutt_is_application_pgp (a))
      return (1);
    if ((WithCrypto & APPLICATION_SMIME) && mutt_is_application_smime (a))
      return (1);
  }

  return (0);
}

static int multipart_handler (BODY * a, STATE * s)
{
  BODY *b, *p;
  char length[5];
  struct stat st;
  int count;
  int rc = 0;

  if (a->encoding == ENCBASE64 || a->encoding == ENCQUOTEDPRINTABLE ||
      a->encoding == ENCUUENCODED) {
    fstat (fileno (s->fpin), &st);
    b = mutt_new_body ();
    b->length = (long) st.st_size;
    b->parts = mutt_parse_multipart (s->fpin,
                                     mutt_get_parameter ("boundary",
                                                         a->parameter),
                                     (long) st.st_size,
                                     ascii_strcasecmp ("digest",
                                                       a->subtype) == 0);
  }
  else
    b = a;

  for (p = b->parts, count = 1; p; p = p->next, count++) {
    if (s->flags & M_DISPLAY) {
      state_mark_attach (s);
      state_printf (s, _("[-- Attachment #%d"), count);
      if (p->description || p->filename || p->form_name) {
        state_puts (": ", s);
        state_puts (p->description ? p->description :
                    p->filename ? p->filename : p->form_name, s);
      }
      state_puts (" --]\n", s);

      mutt_pretty_size (length, sizeof (length), p->length);

      state_mark_attach (s);
      state_printf (s, _("[-- Type: %s/%s, Encoding: %s, Size: %s --]\n"),
                    TYPE (p), p->subtype, ENCODING (p->encoding), length);
      if (!option (OPTWEED)) {
        fseeko (s->fpin, p->hdr_offset, 0);
        mutt_copy_bytes (s->fpin, s->fpout, p->offset - p->hdr_offset);
      }
      else
        state_putc ('\n', s);
    }
    else {
      if (p->description && mutt_can_decode (p))
        state_printf (s, "Content-Description: %s\n", p->description);

      if (p->form_name)
        state_printf (s, "%s: \n", p->form_name);

    }
    rc = mutt_body_handler (p, s);
    state_putc ('\n', s);
    if (rc || ((s->flags & M_REPLYING)
        && (option (OPTINCLUDEONLYFIRST)) && (s->flags & M_FIRSTDONE)))
      break;
  }

  if (a->encoding == ENCBASE64 || a->encoding == ENCQUOTEDPRINTABLE ||
      a->encoding == ENCUUENCODED)
    mutt_free_body (&b);

  return (rc);
}

static int autoview_handler (BODY * a, STATE * s)
{
  rfc1524_entry *entry = rfc1524_new_entry ();
  char buffer[LONG_STRING];
  char type[STRING];
  char command[LONG_STRING];
  char tempfile[_POSIX_PATH_MAX] = "";
  char *fname;
  FILE *fpin = NULL;
  FILE *fpout = NULL;
  FILE *fperr = NULL;
  int piped = FALSE;
  pid_t thepid;
  int rc = 0;

  snprintf (type, sizeof (type), "%s/%s", TYPE (a), a->subtype);
  rfc1524_mailcap_lookup (a, type, entry, M_AUTOVIEW);

  fname = str_dup (a->filename);
  mutt_sanitize_filename (fname, 1);
  rfc1524_expand_filename (entry->nametemplate, fname, tempfile,
                           sizeof (tempfile));
  mem_free (&fname);

  if (entry->command) {
    strfcpy (command, entry->command, sizeof (command));

    /* rfc1524_expand_command returns 0 if the file is required */
    piped =
      rfc1524_expand_command (a, tempfile, type, command, sizeof (command));

    if (s->flags & M_DISPLAY) {
      state_mark_attach (s);
      state_printf (s, _("[-- Autoview using %s --]\n"), command);
      mutt_message (_("Invoking autoview command: %s"), command);
    }

    if ((fpin = safe_fopen (tempfile, "w+")) == NULL) {
      mutt_perror ("fopen");
      rfc1524_free_entry (&entry);
      return (-1);
    }

    mutt_copy_bytes (s->fpin, fpin, a->length);

    if (!piped) {
      safe_fclose (&fpin);
      thepid = mutt_create_filter (command, NULL, &fpout, &fperr);
    }
    else {
      unlink (tempfile);
      fflush (fpin);
      rewind (fpin);
      thepid = mutt_create_filter_fd (command, NULL, &fpout, &fperr,
                                      fileno (fpin), -1, -1);
    }

    if (thepid < 0) {
      mutt_perror (_("Can't create filter"));

      if (s->flags & M_DISPLAY) {
        state_mark_attach (s);
        state_printf (s, _("[-- Can't run %s. --]\n"), command);
      }
      rc = -1;
      goto bail;
    }

    if (s->prefix) {
      while (fgets (buffer, sizeof (buffer), fpout) != NULL) {
        state_puts (s->prefix, s);
        state_puts (buffer, s);
      }
      /* check for data on stderr */
      if (fgets (buffer, sizeof (buffer), fperr)) {
        if (s->flags & M_DISPLAY) {
          state_mark_attach (s);
          state_printf (s, _("[-- Autoview stderr of %s --]\n"), command);
        }

        state_puts (s->prefix, s);
        state_puts (buffer, s);
        while (fgets (buffer, sizeof (buffer), fperr) != NULL) {
          state_puts (s->prefix, s);
          state_puts (buffer, s);
        }
      }
    }
    else {
      mutt_copy_stream (fpout, s->fpout);
      /* Check for stderr messages */
      if (fgets (buffer, sizeof (buffer), fperr)) {
        if (s->flags & M_DISPLAY) {
          state_mark_attach (s);
          state_printf (s, _("[-- Autoview stderr of %s --]\n"), command);
        }

        state_puts (buffer, s);
        mutt_copy_stream (fperr, s->fpout);
      }
    }

  bail:
    safe_fclose (&fpout);
    safe_fclose (&fperr);

    mutt_wait_filter (thepid);
    if (piped)
      safe_fclose (&fpin);
    else
      mutt_unlink (tempfile);

    if (s->flags & M_DISPLAY)
      mutt_clear_error ();
  }
  rfc1524_free_entry (&entry);
  return (rc);
}

static int external_body_handler (BODY * b, STATE * s)
{
  const char *access_type;
  const char *expiration;
  time_t expire;

  access_type = mutt_get_parameter ("access-type", b->parameter);
  if (!access_type) {
    if (s->flags & M_DISPLAY) {
      state_mark_attach (s);
      state_puts (_("[-- Error: message/external-body has no access-type parameter --]\n"), s);
    }
    return (-1);
  }

  expiration = mutt_get_parameter ("expiration", b->parameter);
  if (expiration)
    expire = mutt_parse_date (expiration, NULL);
  else
    expire = -1;

  if (!ascii_strcasecmp (access_type, "x-mutt-deleted")) {
    if (s->flags & (M_DISPLAY | M_PRINTING)) {
      char *length;
      char pretty_size[10];

      state_mark_attach (s);
      state_printf (s, _("[-- This %s/%s attachment "),
                    TYPE (b->parts), b->parts->subtype);
      length = mutt_get_parameter ("length", b->parameter);
      if (length) {
        mutt_pretty_size (pretty_size, sizeof (pretty_size),
                          strtol (length, NULL, 10));
        state_printf (s, _("(size %s bytes) "), pretty_size);
      }
      state_puts (_("has been deleted --]\n"), s);

      if (expire != -1) {
        state_mark_attach (s);
        state_printf (s, _("[-- on %s --]\n"), expiration);
      }
      if (b->parts->filename) {
        state_mark_attach (s);
        state_printf (s, _("[-- name: %s --]\n"), b->parts->filename);
      }

      mutt_copy_hdr (s->fpin, s->fpout, ftello (s->fpin), b->parts->offset,
                     (option (OPTWEED) ? (CH_WEED | CH_REORDER) : 0) |
                     CH_DECODE, NULL);
    }
  }
  else if (expiration && expire < time (NULL)) {
    if (s->flags & M_DISPLAY) {
      state_mark_attach (s);
      state_printf (s, _("[-- This %s/%s attachment is not included, --]\n"),
                    TYPE (b->parts), b->parts->subtype);
      state_attach_puts (_("[-- and the indicated external source has --]\n"
                           "[-- expired. --]\n"), s);

      mutt_copy_hdr (s->fpin, s->fpout, ftello (s->fpin), b->parts->offset,
                     (option (OPTWEED) ? (CH_WEED | CH_REORDER) : 0) |
                     CH_DECODE, NULL);
    }
  }
  else {
    if (s->flags & M_DISPLAY) {
      state_mark_attach (s);
      state_printf (s,
                    _("[-- This %s/%s attachment is not included, --]\n"),
                    TYPE (b->parts), b->parts->subtype);
      state_mark_attach (s);
      state_printf (s,
                    _
                    ("[-- and the indicated access-type %s is unsupported --]\n"),
                    access_type);
      mutt_copy_hdr (s->fpin, s->fpout, ftello (s->fpin), b->parts->offset,
                     (option (OPTWEED) ? (CH_WEED | CH_REORDER) : 0) |
                     CH_DECODE, NULL);
    }
  }
  return (0);
}

void mutt_decode_attachment (BODY * b, STATE * s)
{
  int istext = mutt_is_text_part (b);
  iconv_t cd = (iconv_t) (-1);

  Quotebuf[0] = '\0';

  if (istext) {
    if (s->flags & M_CHARCONV) {
      char *charset = mutt_get_parameter ("charset", b->parameter);

      if (!option (OPTSTRICTMIME) && !charset)
        charset = mutt_get_first_charset (AssumedCharset);
      if (charset && Charset)
        cd = mutt_iconv_open (Charset, charset, M_ICONV_HOOK_FROM);
    }
    else {
      if (b->file_charset)
        cd = mutt_iconv_open (Charset, b->file_charset, M_ICONV_HOOK_FROM);
    }
  }

  fseeko (s->fpin, b->offset, 0);
  switch (b->encoding) {
  case ENCQUOTEDPRINTABLE:
    mutt_decode_quoted (s, b->length, istext ||
                        ((WithCrypto & APPLICATION_PGP) &&
                         mutt_is_application_pgp (b)), cd);
    break;
  case ENCBASE64:
    mutt_decode_base64 (s, b->length, istext ||
                        ((WithCrypto & APPLICATION_PGP) &&
                         mutt_is_application_pgp (b)), cd);
    break;
  case ENCUUENCODED:
    mutt_decode_uuencoded (s, b->length, istext
                           || ((WithCrypto & APPLICATION_PGP) &&
                               mutt_is_application_pgp (b)), cd);
    break;
  default:
    mutt_decode_xbit (s, b->length, istext
                      || ((WithCrypto & APPLICATION_PGP) &&
                          mutt_is_application_pgp (b)), cd);
    break;
  }

  if (cd != (iconv_t) (-1))
    iconv_close (cd);
}

int mutt_body_handler (BODY * b, STATE * s)
{
  int decode = 0;
  int plaintext = 0;
  FILE *fp = NULL;
  char tempfile[_POSIX_PATH_MAX];
  handler_t handler = NULL;
  long tmpoffset = 0;
  size_t tmplength = 0;
  char type[STRING];
  int rc = 0;

  int oflags = s->flags;

  /* first determine which handler to use to process this part */

  snprintf (type, sizeof (type), "%s/%s", TYPE (b), b->subtype);
  if (mutt_is_autoview (b, type)) {
    rfc1524_entry *entry = rfc1524_new_entry ();

    if (rfc1524_mailcap_lookup (b, type, entry, M_AUTOVIEW)) {
      handler = autoview_handler;
      s->flags &= ~M_CHARCONV;
    }
    rfc1524_free_entry (&entry);
  }
  else if (b->type == TYPETEXT) {
    if (ascii_strcasecmp ("plain", b->subtype) == 0) {
      /* avoid copying this part twice since removing the transfer-encoding is
       * the only operation needed.
       */
      if ((WithCrypto & APPLICATION_PGP) && mutt_is_application_pgp (b))
        handler = crypt_pgp_application_pgp_handler;
      else
        if (ascii_strcasecmp
            ("flowed", mutt_get_parameter ("format", b->parameter)) == 0)
        handler = rfc3676_handler;
      else
        plaintext = 1;
    }
    else if (ascii_strcasecmp ("enriched", b->subtype) == 0)
      handler = text_enriched_handler;
    else                        /* text body type without a handler */
      plaintext = 1;
  }
  else if (b->type == TYPEMESSAGE) {
    if (mutt_is_message_type (b->type, b->subtype))
      handler = message_handler;
    else if (!ascii_strcasecmp ("delivery-status", b->subtype))
      plaintext = 1;
    else if (!ascii_strcasecmp ("external-body", b->subtype))
      handler = external_body_handler;
  }
  else if (b->type == TYPEMULTIPART) {
    char *p;

    if (ascii_strcasecmp ("alternative", b->subtype) == 0)
      handler = alternative_handler;
    else if (WithCrypto && ascii_strcasecmp ("signed", b->subtype) == 0) {
      p = mutt_get_parameter ("protocol", b->parameter);

      if (!p)
        mutt_error (_("Error: multipart/signed has no protocol."));

      else if (s->flags & M_VERIFY)
        handler = mutt_signed_handler;
    }
    else if ((WithCrypto & APPLICATION_PGP)
             && str_casecmp ("encrypted", b->subtype) == 0) {
      p = mutt_get_parameter ("protocol", b->parameter);

      if (!p)
        mutt_error (_
                    ("Error: multipart/encrypted has no protocol parameter!"));

      else if (ascii_strcasecmp ("application/pgp-encrypted", p) == 0)
        handler = crypt_pgp_encrypted_handler;
    }

    if (!handler)
      handler = multipart_handler;
  }
  else if (WithCrypto && b->type == TYPEAPPLICATION) {
    if ((WithCrypto & APPLICATION_PGP) && mutt_is_application_pgp (b))
      handler = crypt_pgp_application_pgp_handler;
    if ((WithCrypto & APPLICATION_SMIME) && mutt_is_application_smime (b))
      handler = crypt_smime_application_smime_handler;
  }


  if (plaintext || handler) {
    fseeko (s->fpin, b->offset, 0);

    /* see if we need to decode this part before processing it */
    if (b->encoding == ENCBASE64 || b->encoding == ENCQUOTEDPRINTABLE || b->encoding == ENCUUENCODED || plaintext || mutt_is_text_part (b)) {   /* text subtypes may
                                                                                                                                                 * require character
                                                                                                                                                 * set conversion even
                                                                                                                                                 * with 8bit encoding.
                                                                                                                                                 */
      int origType = b->type;
      char *savePrefix = NULL;

      if (!plaintext) {
        /* decode to a tempfile, saving the original destination */
        fp = s->fpout;
        mutt_mktemp (tempfile);
        if ((s->fpout = safe_fopen (tempfile, "w")) == NULL) {
          mutt_error _("Unable to open temporary file!");

          goto bail;
        }
        /* decoding the attachment changes the size and offset, so save a copy
         * of the "real" values now, and restore them after processing
         */
        tmplength = b->length;
        tmpoffset = b->offset;

        /* if we are decoding binary bodies, we don't want to prefix each
         * line with the prefix or else the data will get corrupted.
         */
        savePrefix = s->prefix;
        s->prefix = NULL;

        decode = 1;
      }
      else
        b->type = TYPETEXT;

      mutt_decode_attachment (b, s);

      if (decode) {
        b->length = ftello (s->fpout);
        b->offset = 0;
        fclose (s->fpout);

        /* restore final destination and substitute the tempfile for input */
        s->fpout = fp;
        fp = s->fpin;
        s->fpin = safe_fopen (tempfile, "r");
        unlink (tempfile);

        /* restore the prefix */
        s->prefix = savePrefix;
      }

      b->type = origType;
    }

    /* process the (decoded) body part */
    if (handler) {
      rc = handler (b, s);

      if (decode) {
        b->length = tmplength;
        b->offset = tmpoffset;

        /* restore the original source stream */
        fclose (s->fpin);
        s->fpin = fp;
      }
    }
    s->flags |= M_FIRSTDONE;
  }
  else if (s->flags & M_DISPLAY) {
    state_mark_attach (s);
    state_printf (s, _("[-- %s/%s is unsupported "), TYPE (b), b->subtype);
    if (!option (OPTVIEWATTACH)) {
      if (km_expand_key
          (type, sizeof (type),
           km_find_func (MENU_PAGER, OP_VIEW_ATTACHMENTS)))
        fprintf (s->fpout, _("(use '%s' to view this part)"), type);
      else
        fputs (_("(need 'view-attachments' bound to key!)"), s->fpout);
    }
    fputs (" --]\n", s->fpout);
  }

bail:
  s->flags = oflags | (s->flags & M_FIRSTDONE);

  return (rc);
}


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