mdw@git.distorted.org.uk Git - disorder/blob - disobedience/help.c

   1 /*
   2  * This file is part of DisOrder
   3  * Copyright (C) 2007 Richard Kettlewell
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  18  * USA
  19  */
  20 /** @file disobedience/help.c
  21  * @brief Help support
  22  */
  23
  24 #include "disobedience.h"
  25 #include "table.h"
  26 #include "html.h"
  27 #include "manual.h"
  28
  29 VECTOR_TYPE(markstack, GtkTextMark *, xrealloc);
  30
  31 /** @brief Known tag type */
  32 struct tag {
  33   /** @brief HTML tag name */
  34   const char *name;
  35
  36   /** @brief Called to set up the tag */
  37   void (*init)(GtkTextTag *tag);
  38
  39   /** @brief GTK+ tag object */
  40   GtkTextTag *tag;
  41 };
  42
  43 /** @brief Initialize the bold tag
  44  *
  45  * This doesn't seem to work on OS X though the italic and monospace tags are
  46  * fine, and bold is OK on Linux, even connecting to the Apple X swerver.
  47  */
  48 static void init_bold(GtkTextTag *tag) {
  49   g_object_set(G_OBJECT(tag), "weight", PANGO_WEIGHT_BOLD, (char *)0);
  50 }
  51
  52 /** @brief Initialize the italic tag */
  53 static void init_italic(GtkTextTag *tag) {
  54   g_object_set(G_OBJECT(tag), "style", PANGO_STYLE_ITALIC, (char *)0);
  55 }
  56
  57 /** @brief Initialize the pre tag */
  58 static void init_pre(GtkTextTag *tag) {
  59   g_object_set(G_OBJECT(tag), "family", "monospace", (char *)0);
  60 }
  61
  62 /** @brief Table of known tags
  63  *
  64  * Keep in alphabetical order
  65  */
  66 static  struct tag tags[] = {
  67   { "b", init_bold, 0 },
  68   { "i", init_italic, 0 },
  69   { "pre", init_pre, 0 }
  70 };
  71
  72 /** @brief Number of known tags */
  73 #define NTAGS (sizeof tags / sizeof *tags)
  74
  75 /** @brief State structure for insert_html() */
  76 struct state {
  77   /** @brief The buffer to insert into */
  78   GtkTextBuffer *buffer;
  79
  80   /** @brief True if we are inside <body> */
  81   int body;
  82
  83   /** @brief True if inside <pre> */
  84   int pre;
  85
  86   /** @brief True if a space is required before any non-space */
  87   int space;
  88
  89   /** @brief Stack of marks corresponding to tags */
  90   struct markstack marks[1];
  91
  92 };
  93
  94 /** @brief Called for an open tag */
  95 static void html_open(const char *tag,
  96                       hash attribute((unused)) *attrs,
  97                       void *u) {
  98   struct state *const s = u;
  99   GtkTextIter iter[1];
 100
 101   if(!strcmp(tag, "body"))
 102     ++s->body;
 103   else if(!strcmp(tag, "pre"))
 104     ++s->pre;
 105   if(!s->body)
 106     return;
 107   /* push a mark for the start of the region */
 108   gtk_text_buffer_get_iter_at_mark(s->buffer, iter,
 109                                    gtk_text_buffer_get_insert(s->buffer));
 110   markstack_append(s->marks,
 111                    gtk_text_buffer_create_mark(s->buffer,
 112                                                0/* mark_name */,
 113                                                iter,
 114                                                TRUE/*left_gravity*/));
 115 }
 116
 117 /** @brief Called for a close tag */
 118 static void html_close(const char *tag,
 119                        void *u) {
 120   struct state *const s = u;
 121   GtkTextIter start[1], end[1];
 122   int n;
 123
 124   if(!strcmp(tag, "body"))
 125     --s->body;
 126   else if(!strcmp(tag, "pre")) {
 127     --s->pre;
 128     s->space = 0;
 129   }
 130   if(!s->body)
 131     return;
 132   /* see if this is a known tag */
 133   if((n = TABLE_FIND(tags, struct tag, name, tag)) < 0)
 134     return;
 135   /* pop the mark at the start of the region */
 136   assert(s->marks->nvec > 0);
 137   gtk_text_buffer_get_iter_at_mark(s->buffer, start,
 138                                    s->marks->vec[--s->marks->nvec]);
 139   gtk_text_buffer_get_iter_at_mark(s->buffer, end,
 140                                    gtk_text_buffer_get_insert(s->buffer));
 141   /* apply a tag */
 142   gtk_text_buffer_apply_tag(s->buffer, tags[n].tag, start, end);
 143   /* don't need the start mark any more */
 144   gtk_text_buffer_delete_mark(s->buffer, s->marks->vec[s->marks->nvec]);
 145 }
 146
 147 /** @brief Called for text */
 148 static void html_text(const char *text,
 149                       void *u) {
 150   struct state *const s = u;
 151
 152   /* ignore header */
 153   if(!s->body)
 154     return;
 155   if(!s->pre) {
 156     char *formatted = xmalloc(strlen(text) + 1), *t = formatted;
 157     /* normalize spacing */
 158     while(*text) {
 159       if(isspace((unsigned char)*text)) {
 160         s->space = 1;
 161         ++text;
 162       } else {
 163         if(s->space) {
 164           *t++ = ' ';
 165           s->space = 0;
 166         }
 167         *t++ = *text++;
 168       }
 169     }
 170     *t = 0;
 171     text = formatted;
 172   }
 173   gtk_text_buffer_insert_at_cursor(s->buffer, text, strlen(text));
 174 }
 175
 176 /** @brief Callbacks for insert_html() */
 177 static const struct html_parser_callbacks insert_html_callbacks = {
 178   html_open,
 179   html_close,
 180   html_text
 181 };
 182
 183 /** @brief Insert @p html into @p buffer at cursor */
 184 static void insert_html(GtkTextBuffer *buffer,
 185                         const char *html) {
 186   struct state s[1];
 187   size_t n;
 188   GtkTextTagTable *tagtable;
 189
 190   memset(s, 0, sizeof *s);
 191   s->buffer = buffer;
 192   markstack_init(s->marks);
 193   /* initialize tags */
 194   if(!tags[0].tag)
 195     for(n = 0; n < NTAGS; ++n)
 196       tags[n].init(tags[n].tag = gtk_text_tag_new(0));
 197   /* add tags to this buffer */
 198   tagtable = gtk_text_buffer_get_tag_table(s->buffer);
 199   for(n = 0; n < NTAGS; ++n)
 200     gtk_text_tag_table_add(tagtable, tags[n].tag);
 201   /* convert the input */
 202   html_parse(&insert_html_callbacks, html, s);
 203 }
 204
 205 /** @brief Create a GtkTextBuffer with @p html rendered into it */
 206 static GtkTextBuffer *html_buffer(const char *html) {
 207   GtkTextBuffer *buffer = gtk_text_buffer_new(NULL);
 208
 209   insert_html(buffer, html);
 210   return buffer;
 211 }
 212
 213 /** @brief The manual page window */
 214 static GtkWidget *help_window;
 215
 216 /** @brief Pop up the manual page in a window */
 217 void popup_help(void) {
 218   GtkWidget *view;
 219
 220   if(help_window) {
 221     gtk_window_present(GTK_WINDOW(help_window));
 222     return;
 223   }
 224   help_window = gtk_window_new(GTK_WINDOW_TOPLEVEL);
 225   g_signal_connect(help_window, "destroy",
 226                    G_CALLBACK(gtk_widget_destroyed), &help_window);
 227   gtk_window_set_title(GTK_WINDOW(help_window), "Disobedience Manual Page");
 228   view = gtk_text_view_new_with_buffer(html_buffer(manual));
 229   gtk_text_view_set_editable(GTK_TEXT_VIEW(view), FALSE);
 230   gtk_container_add(GTK_CONTAINER(help_window),
 231                     scroll_widget(view,
 232                                   "help"));
 233   gtk_window_set_default_size(GTK_WINDOW(help_window), 512, 512);
 234   gtk_widget_show_all(help_window);
 235 }
 236
 237 /*
 238 Local Variables:
 239 c-basic-offset:2
 240 comment-column:40
 241 fill-column:79
 242 indent-tabs-mode:nil
 243 End:
 244 */