#include "mess822.h"
#include "str.h"

static stralloc tokens = {0};

static stralloc comment = {0};

static stralloc addr = {0};
static int state; /* 0: no address; 1: address without @; 2: address with @ */

static int docomment(out)
stralloc *out;
{
  int i;
  int j;
  char ch;

  for (j = i = 0;j < comment.len;++j) {
    ch = comment.s[j];
    if (ch == ' ') if (!i || (comment.s[i - 1] == ' ')) continue;
    comment.s[i++] = ch;
  }
  while (i && (comment.s[i - 1] == ' ')) --i;
  comment.len = 0;

  if (i) {
    if (!stralloc_0(out)) return 0;
    if (!stralloc_catb(out,comment.s,i)) return 0;
    if (!stralloc_append(out,"(")) return 0;
  }

  return 1;
}

static int doit(out)
stralloc *out;
{
  int i;

  if (!state) return 1;

  if (!stralloc_0(out)) return 0;
  if (state == 1)
    if (!stralloc_append(out,"@")) return 0;
  if (!stralloc_catb(out,addr.s,addr.len)) return 0;
  if (!stralloc_append(out,"+")) return 0;

  if (!docomment(out)) return 0;

  state = 0;
  addr.len = 0;
  return 1;
}

static int addcomment(tok)
char *tok;
{
  int i;

  if (*tok == ',') return 1;
  if (*tok == ':') return 1;
  if (*tok == ';') return 1;
  if (*tok == '<') return 1;
  if (*tok == '>') return 1;

  if ((*tok == '=') || (*tok == '(')) ++tok;

  i = str_len(tok);
  while (i--)
    if (!stralloc_append(&comment,tok + i)) return 0;

  return 1;
}

static int addaddr(tok)
char *tok;
{
  int i;

  if ((*tok != '=') && (*tok != '.') && (*tok != '@'))
    return addcomment(tok);

  if (!state) state = 1;
  if (*tok == '@') state = 2;

  if (*tok == '=') ++tok;

  i = str_len(tok);
  while (i--)
    if (!stralloc_append(&addr,tok + i)) return 0;

  return 1;
}

int mess822_addrlist(out,in)
stralloc *out;
char *in;
{
  int flagwordok = 1;
  int flagphrase = 0;
  int j;
  int i;
  char ch;

  if (!mess822_token(&tokens,in)) return 0;

  if (!stralloc_copys(out,"")) return 0;
  if (!stralloc_copys(&comment,"")) return 0;
  if (!stralloc_copys(&addr,"")) return 0;
  state = 0;

  j = tokens.len;

  while (j) {
    while (j--) if (!j || !tokens.s[j - 1]) break;

    ch = tokens.s[j];
    if (flagphrase) {
      if ((ch != ',') && (ch != ';') && (ch != ':') && (ch != '>')) {
        if (!addcomment(tokens.s + j)) return 0;
        continue;
      }
      if (!doit(out)) return 0;
      flagphrase = 0;
      flagwordok = 1;
    }

    switch(tokens.s[j]) {
      case ' ': case '\t':
        if (!addcomment(" ")) return 0;
        break;

      case ';': case ',':
        if (!doit(out)) return 0;
        if (!docomment(out)) return 0;
        flagwordok = 1;
        break;

      case '(':
        if (!addcomment(" ")) return 0;
        if (!addcomment(tokens.s + j)) return 0;
        if (!addcomment(" ")) return 0;
        break;

      case '=':
        if (!flagwordok)
          if (!doit(out)) return 0;
        if (!addaddr(tokens.s + j)) return 0;
        flagwordok = 0;
        break;

      case '>':
        if (!doit(out)) return 0;

        if (!state) state = 1; /* <> is an address */

        for (;;) {
          if (!addaddr(tokens.s + j)) return 0;
          if (!j) break;
          while (j--) if (!j || !tokens.s[j - 1]) break;
          if (tokens.s[j] == ':') break;
          if (tokens.s[j] == '<') break;
        }

        if (tokens.s[j] == ':')
          for (;;) {
            if (!addcomment(tokens.s + j)) return 0;
            if (!j) break;
            while (j--) if (!j || !tokens.s[j - 1]) break;
            if (tokens.s[j] == '<') break;
          }
	/* fall through */

      case ':':
        flagphrase = 1;
        break;

      default:
        if (!addaddr(tokens.s + j)) return 0;
        flagwordok = 1;
        break;
    }
  }

  if (!doit(out)) return 0;
  if (!docomment(out)) return 0;

  i = 0;
  j = out->len - 1;

  while (i < j) {
    ch = out->s[i];
    out->s[i] = out->s[j];
    out->s[j] = ch;
    ++i;
    --j;
  }

  return 1;
}