eeshow/: make WebKit optional; add Gtk-based fallback viewer

eeshow/Makefile

@@ -27,13 +27,19 @@ CFLAGS = -g  -Wall -Wextra -Wno-unused-parameter -Wshadow \
 	 -I. \
 	 `pkg-config --cflags cairo` \
 	 `pkg-config --cflags libgit2` \
-	 `pkg-config --cflags gtk+-3.0` \
+	 `pkg-config --cflags gtk+-3.0`
-	 `pkg-config --cflags webkit2gtk-4.0`
 LDLIBS = -lm \
 	 `pkg-config --libs cairo` \
 	 `pkg-config --libs libgit2` \
-	 `pkg-config --libs gtk+-3.0` \
+	 `pkg-config --libs gtk+-3.0`
-	 `pkg-config --libs webkit2gtk-4.0`
+
+ifneq ($(USE_WEBKIT),)
+	CFLAGS += -DUSE_WEBKIT `pkg-config --cflags webkit2gtk-4.0`
+	LDLIBS += `pkg-config --libs webkit2gtk-4.0`
+	HELP_TEXT = help.html
+else
+	HELP_TEXT = help.txt
+endif
 
 include ../common/Makefile.c-common
 
@@ -44,8 +50,9 @@ all::		$(NAME)
 $(NAME):	$(OBJS)
 		$(CC) -o $(NAME) $(OBJS) $(LDLIBS)
 
-help.inc:	help.html
+help.inc:	$(HELP_TEXT) Makefile
-		$(BUILD) sed 's/.*/"&"/' $< >$@ || { rm -f $@; exit 1; }
+		$(BUILD) sed 's/"/\\"/g;s/.*/"&\\n"/' $< >$@ || \
+		    { rm -f $@; exit 1; }
 
 gui/help.c:	help.inc
 

eeshow/gui/help.c

@@ -13,7 +13,10 @@
 #include <stdbool.h>
 
 #include <gtk/gtk.h>
+
+#ifdef USE_WEBKIT
 #include <webkit2/webkit2.h>
+#endif
 
 #include "gui/help.h"
 
@@ -29,25 +32,81 @@ static void destroy_help(GtkWidget *object, gpointer user_data)
 }
 
 
-static void new_help_window(void)
+static gboolean key_press_event(GtkWidget *widget, GdkEventKey *event,
+    gpointer data)
+{
+	switch (event->keyval) {
+	case GDK_KEY_h:
+	case GDK_KEY_question:
+	case GDK_KEY_q:
+		gtk_widget_hide(window);
+		visible = 0;
+		break;
+	}
+	return TRUE;
+}
+
+
+#ifdef USE_WEBKIT
+
+static GtkWidget *help_content(void)
 {
 	GtkWidget *view;
 	WebKitSettings *settings;
 
-	window = gtk_window_new(GTK_WINDOW_TOPLEVEL);
 	view = webkit_web_view_new();
 
 	settings = webkit_web_view_get_settings(WEBKIT_WEB_VIEW(view));
 	webkit_settings_set_default_font_size(settings, 10);
 
-	gtk_container_add(GTK_CONTAINER(window), view);
-	gtk_window_set_default_size(GTK_WINDOW(window), 480, 360);
-	gtk_widget_show_all(window);
-
 	webkit_web_view_load_html(WEBKIT_WEB_VIEW(view),
 #include "../help.inc"
 	, NULL);
 
+	return view;
+}
+
+#else /* USE_WEBKIT */
+
+static GtkWidget *help_content(void)
+{
+	GtkWidget *scroll, *label;
+
+	scroll = gtk_scrolled_window_new(NULL, NULL);
+	label = gtk_label_new(NULL);
+
+	gtk_scrolled_window_set_policy(GTK_SCROLLED_WINDOW(scroll),
+            GTK_POLICY_NEVER, GTK_POLICY_AUTOMATIC);
+
+	gtk_label_set_line_wrap(GTK_LABEL(label), TRUE);
+	gtk_label_set_markup(GTK_LABEL(label),
+#include "../help.inc"
+	    );
+
+	gtk_container_add(GTK_CONTAINER(scroll), label);
+
+	return scroll;
+}
+
+#endif /* !USE_WEBKIT */
+
+
+static void new_help_window(void)
+{
+	GtkWidget *content;
+
+	window = gtk_window_new(GTK_WINDOW_TOPLEVEL);
+	content = help_content();
+
+	gtk_container_add(GTK_CONTAINER(window), content);
+	gtk_window_set_default_size(GTK_WINDOW(window), 480, 360);
+	gtk_widget_show_all(window);
+
+	gtk_widget_set_can_focus(content, TRUE);
+	gtk_widget_add_events(content, GDK_KEY_PRESS_MASK);
+
+	g_signal_connect(G_OBJECT(content), "key_press_event",
+	    G_CALLBACK(key_press_event), NULL);
 	g_signal_connect(window, "destroy", G_CALLBACK(destroy_help), NULL);
 
 	gtk_widget_show_all(window);

eeshow/help.html

@@ -42,7 +42,7 @@
     <TD>show older sheet
   <TR>
     <TD>Q
-    <TD>quit the vieweer
+    <TD>quit the viewer
 </TABLE>
 </BODY>
 </HTML>

eeshow/help.txt

@@ -0,0 +1,17 @@
+<span font_desc="Mono 10">
++ or =      zoom in
+-           zoom out
+*           zoom to extents
+Home        go to the top sheet
+Delete or
+Backspace   go to the next higher sheet in hierarchy
+PgUp        go to the previous sheet in sequence
+PgDn        go to the next sheet in sequence
+Up or Down  invoke the revision history (WIP)
+Tab         toggle between old and new revision
+? or H      show/hide help window
+D           when comparing revisions, show difference
+N           show newer sheet
+O           show older sheet
+Q           quit the viewer
+</span>