A framework for pick command

+/* GNU Mailutils -- a suite of utilities for electronic mail
+   Copyright (C) 2003 Free Software Foundation, Inc.
+
+   GNU Mailutils is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2, or (at your option)
+   any later version.
+
+   GNU Mailutils is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with GNU Mailutils; if not, write to the Free Software
+   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307  USA  */
+
+/* MH pick command */
+
+#include <mh.h>
+#include <regex.h>
+
+const char *argp_program_version = "pick (" PACKAGE_STRING ")";
+static char doc[] = N_("GNU MH pick\v"
+"Options marked with `*' are not yet implemented.\n"
+"Use -help to obtain the list of traditional MH options.");
+static char args_doc[] = N_("[messages]");
+
+/* GNU options */
+static struct argp_option options[] = {
+  {"folder",  ARG_FOLDER, N_("FOLDER"), 0,
+   N_("Specify folder to operate upon"), 0},
+
+  {N_("Specifying search patterns:"), 0,  NULL, OPTION_DOC,  NULL, 0},
+  {"component", ARG_COMPONENT, N_("FIELD"), 0,
+   N_("Search the named header field"), 1},
+  {"pattern", ARG_PATTERN, N_("STRING"), 0,
+   N_("A pattern to look for"), 1},
+  {"search",  0, NULL, OPTION_ALIAS, NULL, 1},
+  {"cc",      ARG_CC,      N_("STRING"), 0,
+   N_("Same as --component cc --pattern STRING"), 1},
+  {"date",    ARG_DATE,    N_("STRING"), 0,
+   N_("Same as --component date --pattern STRING"), 1},
+  {"from",    ARG_FROM,    N_("STRING"), 0,
+   N_("Same as --component from --pattern STRING"), 1},
+  {"subject", ARG_SUBJECT, N_("STRING"), 0,
+   N_("Same as --component subject --pattern STRING"), 1},
+  {"to",      ARG_TO,      N_("STRING"), 0,
+   N_("Same as --component to --pattern STRING"), 1},
+
+  {N_("Date constraint operations:"), 0,  NULL, OPTION_DOC, NULL, 1},
+  {"datefield",ARG_DATEFIELD, N_("STRING"), 0,
+   N_("Search in the named date header field (default is `Date:')"), 2},
+  {"after",    ARG_AFTER,     N_("DATE"), 0,
+   N_("Match messages after the given date"), 2},
+  {"before",   ARG_BEFORE,    N_("DATE"), 0,
+   N_("Match messages before the given date"), 2},
+
+  {N_("Logical operations and grouping:"), 0, NULL, OPTION_DOC, NULL, 2},
+  {"and",     ARG_AND,    NULL, 0,
+   N_("Logical AND (default)"), 3 },
+  {"or",      ARG_OR,     NULL, 0,
+   N_("Logical OR"), 3 },
+  {"not",     ARG_NOT,    NULL, 0,
+   N_("Logical NOT"), 3},
+  {"lbrace",  ARG_LBRACE, NULL, 0,
+   N_("Open group"), 3},
+  {"(",       0, NULL, OPTION_ALIAS, NULL, 3},
+  {"rbrace",  ARG_RBRACE, NULL, 0,
+   N_("Close group"), 3},
+  {")",       0, NULL, OPTION_ALIAS, NULL, 3},
+
+  {N_("Operations over the selected messages:"), 0, NULL, OPTION_DOC, NULL, 3},
+  {"list",   ARG_LIST,       N_("BOOL"), OPTION_ARG_OPTIONAL,
+   N_("List the numbers of the selected messages (default)"), 4},
+  {"nolist", ARG_NOLIST,     NULL, OPTION_HIDDEN, "", 4 },
+  {"sequence", ARG_SEQUENCE,  N_("NAME"), 0,
+   N_("Add matching messages to the given sequence"), 4},
+  {"public", ARG_PUBLIC, N_("BOOL"), OPTION_ARG_OPTIONAL,
+   N_("Create public sequence"), 4},
+  {"nopublic", ARG_NOPUBLIC, NULL, OPTION_HIDDEN, "", 4 },
+  {"zero",     ARG_ZERO,     N_("BOOL"), OPTION_ARG_OPTIONAL,
+   N_("Empty the sequence before adding messages"), 4},
+  {"nozero", ARG_NOZERO, NULL, OPTION_HIDDEN, "", 4 },
+  {NULL},
+};
+
+/* Traditional MH options */
+struct mh_option mh_option[] = {
+  {"component", 1,  0, "field" },
+  {"pattern",   1,  0, "pattern" },
+  {"search",    1,  0, "pattern" },
+  {"cc",        1,  0, "pattern" },
+  {"date",      1,  0, "pattern" },
+  {"from",      1,  0, "pattern" },
+  {"subject",   1,  0, "pattern" },
+  {"to",        1,  0, "pattern" },
+  {"datefield", 1,  0, "field" },
+  {"after",     1,  0, "date" },
+  {"before",    1,  0, "date"},
+  {"and",       1,  0, NULL },
+  {"or",        1,  0, NULL }, 
+  {"not",       1,  0, NULL },
+  {"lbrace",    1,  0, NULL },
+  {"rbrace",    1,  0, NULL },
+
+  {"list",      1,  MH_OPT_BOOL, },
+  {"sequence",  1,  0, NULL },
+  {"public",    1,  MH_OPT_BOOL },
+  {"zero",      1,  MH_OPT_BOOL },
+  {NULL}
+};
+
+static int list;
+static int mode_public = 1;
+static int mode_zero = 0;
+
+static int
+opt_handler (int key, char *arg, void *unused)
+{
+  switch (key)
+    {
+    case '+':
+    case ARG_FOLDER: 
+      current_folder = arg;
+      break;
+
+    case ARG_SEQUENCE:
+      /*  add_sequence (arg); */
+      break;
+
+    case ARG_LIST:
+      list = is_true (arg);
+      break;
+
+    case ARG_NOLIST:
+      list = 0;
+      break;
+
+    case ARG_COMPONENT:      
+    case ARG_PATTERN:        
+    case ARG_CC:              
+    case ARG_DATE:           
+    case ARG_FROM:           
+    case ARG_SUBJECT:        
+    case ARG_TO:             
+    case ARG_DATEFIELD:
+    case ARG_AFTER:
+    case ARG_BEFORE:
+    case ARG_AND:
+    case ARG_OR:
+    case ARG_NOT:
+    case ARG_LBRACE:
+    case ARG_RBRACE:
+      break;
+      
+    case ARG_PUBLIC:
+      mode_public = is_true (arg);
+      break;
+      
+    case ARG_NOPUBLIC:
+      mode_public = 0;
+      break;
+      
+    case ARG_ZERO:
+      mode_zero = is_true (arg);
+      break;
+
+    case ARG_NOZERO:
+      mode_zero = 0;
+      break;
+
+    default:
+      return 1;
+    }
+  return 0;
+}
+
+int
+main (int argc, char **argv)
+{
+  int index;
+
+  mu_init_nls ();
+  mh_argp_parse (argc, argv, options, mh_option, args_doc, doc,
+		 opt_handler, NULL, &index);
+}
+