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 "html.h"
  26 #include "manual.h"
  27
  28 VECTOR_TYPE(markstack, GtkTextMark *, xrealloc);
  29
  30 /** @brief Known tag type */
  31 struct tag {
  32   /** @brief HTML tag name */
  33   const char *name;
  34
  35   /** @brief Called to set up the tag */
  36   void (*init)(GtkTextTag *tag);
  37
  38 };
  39
  40 /** @brief Initialize the bold tag
  41  *
  42  * This doesn't seem to work on OS X though the italic and monospace tags are
  43  * fine, and bold is OK on Linux, even connecting to the Apple X swerver.
  44  */
  45 static void init_bold(GtkTextTag *tag) {
  46   g_object_set(G_OBJECT(tag), "weight", PANGO_WEIGHT_BOLD, (char *)0);
  47 }
  48
  49 /** @brief Initialize the italic tag */
  50 static void init_italic(GtkTextTag *tag) {
  51   g_object_set(G_OBJECT(tag), "style", PANGO_STYLE_ITALIC, (char *)0);
  52 }
  53
  54 /** @brief Initialize the pre tag */
  55 static void init_pre(GtkTextTag *tag) {
  56   g_object_set(G_OBJECT(tag), "family", "monospace", (char *)0);
  57 }
  58
  59 /** @brief Table of known tags
  60  *
  61  * Keep in alphabetical order
  62  */
  63 static const struct tag tags[] = {
  64   { "b", init_bold },
  65   { "i", init_italic },
  66   { "pre", init_pre }
  67 };
  68
  69 /** @brief Number of known tags */
  70 #define NTAGS (sizeof tags / sizeof *tags)
  71
  72 /** @brief State structure for insert_html() */
  73 struct state {
  74   /** @brief The buffer to insert into */
  75   GtkTextBuffer *buffer;
  76
  77   /** @brief The buffer's tag table */
  78   GtkTextTagTable *tagtable;
  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   GtkTextTag *texttag;
 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   texttag = gtk_text_tag_table_lookup(s->tagtable, tag);
 134   if(!texttag)
 135     return;
 136   /* pop the mark at the start of the region */
 137   assert(s->marks->nvec > 0);
 138   gtk_text_buffer_get_iter_at_mark(s->buffer, start,
 139                                    s->marks->vec[--s->marks->nvec]);
 140   gtk_text_buffer_get_iter_at_mark(s->buffer, end,
 141                                    gtk_text_buffer_get_insert(s->buffer));
 142   /* apply the tag */
 143   gtk_text_buffer_apply_tag(s->buffer, texttag, start, end);
 144   /* don't need the start mark any more */
 145   gtk_text_buffer_delete_mark(s->buffer, s->marks->vec[s->marks->nvec]);
 146 }
 147
 148 /** @brief Called for text */
 149 static void html_text(const char *text,
 150                       void *u) {
 151   struct state *const s = u;
 152
 153   /* ignore header */
 154   if(!s->body)
 155     return;
 156   if(!s->pre) {
 157     char *formatted = xmalloc(strlen(text) + 1), *t = formatted;
 158     /* normalize spacing */
 159     while(*text) {
 160       if(isspace((unsigned char)*text)) {
 161         s->space = 1;
 162         ++text;
 163       } else {
 164         if(s->space) {
 165           *t++ = ' ';
 166           s->space = 0;
 167         }
 168         *t++ = *text++;
 169       }
 170     }
 171     *t = 0;
 172     text = formatted;
 173   }
 174   gtk_text_buffer_insert_at_cursor(s->buffer, text, strlen(text));
 175 }
 176
 177 /** @brief Callbacks for insert_html() */
 178 static const struct html_parser_callbacks insert_html_callbacks = {
 179   html_open,
 180   html_close,
 181   html_text
 182 };
 183
 184 /** @brief Insert @p html into @p buffer at cursor */
 185 static void insert_html(GtkTextBuffer *buffer,
 186                         const char *html) {
 187   struct state s[1];
 188   size_t n;
 189
 190   memset(s, 0, sizeof *s);
 191   s->buffer = buffer;
 192   markstack_init(s->marks);
 193   /* initialize tags */
 194   s->tagtable = gtk_text_buffer_get_tag_table(s->buffer);
 195   for(n = 0; n < NTAGS; ++n) {
 196     GtkTextTag *const tag = gtk_text_tag_new(tags[n].name);
 197     tags[n].init(tag);
 198     gtk_text_tag_table_add(s->tagtable, tag);
 199   }
 200   /* convert the input */
 201   html_parse(&insert_html_callbacks, html, s);
 202 }
 203
 204 /** @brief Create a GtkTextBuffer with @p html rendered into it */
 205 static GtkTextBuffer *html_buffer(const char *html) {
 206   GtkTextBuffer *buffer = gtk_text_buffer_new(NULL);
 207
 208   insert_html(buffer, html);
 209   return buffer;
 210 }
 211
 212 /** @brief The manual page window */
 213 static GtkWidget *help_window;
 214
 215 /** @brief Pop up the manual page in a window */
 216 void popup_help(void) {
 217   GtkWidget *view;
 218
 219   if(help_window) {
 220     gtk_window_present(GTK_WINDOW(help_window));
 221     return;
 222   }
 223   help_window = gtk_window_new(GTK_WINDOW_TOPLEVEL);
 224   g_signal_connect(help_window, "destroy",
 225                    G_CALLBACK(gtk_widget_destroyed), &help_window);
 226   gtk_window_set_title(GTK_WINDOW(help_window), "Disobedience Manual Page");
 227   view = gtk_text_view_new_with_buffer(html_buffer(manual));
 228   gtk_text_view_set_editable(GTK_TEXT_VIEW(view), FALSE);
 229   gtk_container_add(GTK_CONTAINER(help_window), scroll_widget(view));
 230   gtk_window_set_default_size(GTK_WINDOW(help_window), 512, 512);
 231   gtk_widget_show_all(help_window);
 232 }
 233
 234 /*
 235 Local Variables:
 236 c-basic-offset:2
 237 comment-column:40
 238 fill-column:79
 239 indent-tabs-mode:nil
 240 End:
 241 */