Refactor statusbar.c

This a preparatory patch. Refactor statusbar.c to compartmentalise the drawing
of the statusbar "widgets". We can now begin to see what a generalised widget
drawing interface would look like.

Note that at the moment we don't gracefully handle situations where "widgets"
run out of space. That will come as we generalise from here.

draw.c

@@ -27,7 +27,6 @@
 #include "util.h"
 #include "draw.h"
 
-
 DrawCtx *
 draw_get_context(Display *display, int phys_screen, int width, int height)
 {

statusbar.c

@@ -30,6 +30,8 @@
 #include "tag.h"
 #include "layouts/tile.h"
 
+enum { AlignLeft, AlignRight, AlignFlex };
+
 /** Check if at least a client is tagged with tag number t and is on screen
  * screen
  * \param t tag number
@@ -47,120 +49,171 @@ isoccupied(TagClientLink *tc, int screen, Client *head, Tag *t)
     return False;
 }
 
+
+static int
+calculate_offset(int barwidth, int widgetwidth, int offset, int alignment)
+{
+    if (alignment == AlignLeft || alignment == AlignFlex)
+        return offset;
+    else
+        return barwidth - offset - widgetwidth;
+}
+
+
+static int
+tagwidget_draw(DrawCtx *ctx,
+               awesome_config *awesomeconf,
+               VirtScreen vscreen,
+               int screen,
+               int offset,
+               int used __attribute__ ((unused)),
+               int align __attribute__ ((unused)))
+{
+    Tag *tag;
+    Client *sel = awesomeconf->focus->client;
+    int w = 0, width = 0, location;
+    int flagsize;
+    XColor *colors;
+
+    flagsize = (vscreen.font->height + 2) / 4;
+
+    for(tag = vscreen.tags; tag; tag = tag->next)
+        width  += textwidth(ctx, vscreen.font, tag->name);
+
+    location = calculate_offset(vscreen.statusbar.width, width, offset, align);
+
+    width = 0;
+    for(tag = vscreen.tags; tag; tag = tag->next)
+    {
+        w = textwidth(ctx, vscreen.font, tag->name);
+        if(tag->selected)
+            colors = vscreen.colors_selected;
+        else
+            colors = vscreen.colors_normal;
+        drawtext(ctx, location + width, 0, w,
+                 vscreen.statusbar.height, vscreen.font, tag->name, colors);
+        if(isoccupied(vscreen.tclink, screen, awesomeconf->clients, tag))
+            drawrectangle(ctx, location + width, 0, flagsize, flagsize,
+                          sel && is_client_tagged(vscreen.tclink, sel, tag),
+                          colors[ColFG]);
+        width += w;
+    }
+    return width;
+}
+
+
+static int
+layoutsymbol_draw(DrawCtx *ctx,
+                  awesome_config *awesomeconf __attribute__ ((unused)),
+                  VirtScreen vscreen,
+                  int screen __attribute__ ((unused)),
+                  int offset, 
+                  int used __attribute__ ((unused)),
+                  int align __attribute__ ((unused)))
+{
+    int width = 0, location; 
+    Layout *l;
+    for(l = vscreen.layouts ; l; l = l->next)
+        width = MAX(width, (textwidth(ctx, vscreen.font, l->symbol)));
+    location = calculate_offset(vscreen.statusbar.width, width, offset, align);
+    drawtext(ctx, location, 0,
+             width,
+             vscreen.statusbar.height,
+             vscreen.font,
+             get_current_layout(vscreen)->symbol,
+             vscreen.colors_normal);
+    return width;
+}
+
+
+static int
+statustext_draw(DrawCtx *ctx,
+                awesome_config *awesomeconf __attribute__ ((unused)),
+                VirtScreen vscreen,
+                int screen __attribute__ ((unused)),
+                int offset, 
+                int used __attribute__ ((unused)),
+                int align)
+{
+    int width = textwidth(ctx, vscreen.font, vscreen.statustext);
+    int location = calculate_offset(vscreen.statusbar.width, width, offset, align);
+    drawtext(ctx, location, 0, width, vscreen.statusbar.height,
+             vscreen.font, vscreen.statustext, vscreen.colors_normal);
+    return width;
+}
+
+
+static int
+focustitle_draw(DrawCtx *ctx,
+                awesome_config *awesomeconf __attribute__ ((unused)),
+                VirtScreen vscreen,
+                int screen __attribute__ ((unused)),
+                int offset, 
+                int used,
+                int align)
+{
+    Client *sel = awesomeconf->focus->client;
+    int location = calculate_offset(vscreen.statusbar.width, 0, offset, align);
+
+    if(sel)
+    {
+        drawtext(ctx, location, 0, vscreen.statusbar.width - used,
+                 vscreen.statusbar.height, vscreen.font, sel->name,
+                 vscreen.colors_selected);
+        if(sel->isfloating)
+            drawcircle(ctx, location, 0,
+                       (vscreen.font->height + 2) / 4,
+                       sel->ismax,
+                       vscreen.colors_selected[ColFG]);
+    }
+    else
+        drawtext(ctx, location, 0, vscreen.statusbar.width - used,
+                 vscreen.statusbar.height, vscreen.font, NULL,
+                 vscreen.colors_normal);
+    return vscreen.statusbar.width - used;
+}
+
+
 void
 statusbar_draw(awesome_config *awesomeconf, int screen)
 {
-    int z, x = 0, y = 0, w;
-    Client *sel = awesomeconf->focus->client;
+    int x = 0, split;
     int phys_screen = get_phys_screen(awesomeconf->display, screen);
-    Statusbar sbar;
-    Tag *tag;
-    Layout *layout;
+    VirtScreen vscreen;
     
-    sbar = awesomeconf->screens[screen].statusbar;
-    DrawCtx *ctx = draw_get_context(awesomeconf->display, phys_screen, sbar.width, sbar.height);
+    vscreen = awesomeconf->screens[screen];
     /* don't waste our time */
-    if(sbar.position == BarOff)
+    if(vscreen.statusbar.position == BarOff)
         return;
 
-    for(tag = awesomeconf->screens[screen].tags; tag; tag = tag->next)
-    {
-        w = textwidth(ctx, awesomeconf->screens[screen].font, tag->name);
-        if(tag->selected)
-        {
-            drawtext(ctx, x, y, w,
-                     sbar.height,
-                     awesomeconf->screens[screen].font,
-                     tag->name,
-                     awesomeconf->screens[screen].colors_selected);
-            if(isoccupied(awesomeconf->screens[screen].tclink, screen, awesomeconf->clients, tag))
-                drawrectangle(ctx, x, y,
-                              (awesomeconf->screens[screen].font->height + 2) / 4,
-                              (awesomeconf->screens[screen].font->height + 2) / 4,
-                              sel && is_client_tagged(awesomeconf->screens[screen].tclink, sel, tag),
-                              awesomeconf->screens[screen].colors_selected[ColFG]);
-        }
-        else
-        {
-            drawtext(ctx, x, y, w,
-                     sbar.height,
-                     awesomeconf->screens[screen].font,
-                     tag->name,
-                     awesomeconf->screens[screen].colors_normal);
-            if(isoccupied(awesomeconf->screens[screen].tclink, screen, awesomeconf->clients, tag))
-                drawrectangle(ctx, x, y,
-                              (awesomeconf->screens[screen].font->height + 2) / 4,
-                              (awesomeconf->screens[screen].font->height + 2) / 4,
-                              sel && is_client_tagged(awesomeconf->screens[screen].tclink, sel, tag),
-                              awesomeconf->screens[screen].colors_normal[ColFG]);
-        }
-        x += w;
-    }
+    DrawCtx *ctx = draw_get_context(awesomeconf->display, phys_screen,
+                                    vscreen.statusbar.width, vscreen.statusbar.height);
+    x += tagwidget_draw(ctx, awesomeconf, vscreen, screen, x, x, AlignLeft);
+    x += layoutsymbol_draw(ctx, awesomeconf, vscreen, screen, x, x, AlignLeft);
+    split = x;
+    x += statustext_draw(ctx, awesomeconf, vscreen, screen, 0, x, AlignRight);
+    focustitle_draw(ctx, awesomeconf, vscreen, screen, split, x, AlignFlex);
 
-    /* This is only here until we refactor this function. */
-    for(layout = awesomeconf->screens[screen].layouts; layout; layout = layout->next)
-        sbar.txtlayoutwidth = MAX(sbar.txtlayoutwidth,
-                                  textwidth(ctx, awesomeconf->screens[screen].font, layout->symbol));
-    drawtext(ctx, x, y,
-             sbar.txtlayoutwidth,
-             sbar.height,
-             awesomeconf->screens[screen].font,
-             get_current_layout(awesomeconf->screens[screen])->symbol,
-             awesomeconf->screens[screen].colors_normal);
-    z = x + sbar.txtlayoutwidth;
-    w = textwidth(ctx, awesomeconf->screens[screen].font, awesomeconf->screens[screen].statustext);
-    x = sbar.width - w;
-    if(x < z)
-    {
-        x = z;
-        w = sbar.width - z;
-    }
-    drawtext(ctx, x, y, w,
-             sbar.height,
-             awesomeconf->screens[screen].font,
-             awesomeconf->screens[screen].statustext,
-             awesomeconf->screens[screen].colors_normal);
-    if((w = x - z) > sbar.height)
-    {
-        x = z;
-        if(sel && sel->screen == screen)
-        {
-            drawtext(ctx, x, y, w,
-                     sbar.height,
-                     awesomeconf->screens[screen].font,
-                     sel->name,
-                     awesomeconf->screens[screen].colors_selected);
-            if(sel->isfloating)
-                drawcircle(ctx, x, y,
-                           (awesomeconf->screens[screen].font->height + 2) / 4,
-                           sel->ismax,
-                           awesomeconf->screens[screen].colors_selected[ColFG]);
-        }
-        else
-            drawtext(ctx, x, y, w,
-                     sbar.height,
-                     awesomeconf->screens[screen].font,
-                     NULL, awesomeconf->screens[screen].colors_normal);
-    }
-    if(sbar.position == BarRight || sbar.position == BarLeft)
+    if(vscreen.statusbar.position == BarRight || vscreen.statusbar.position == BarLeft)
     {
         Drawable d;
-        if(sbar.position == BarRight)
-            d = draw_rotate(ctx, phys_screen, M_PI_2, sbar.height, 0);
+        if(vscreen.statusbar.position == BarRight)
+            d = draw_rotate(ctx, phys_screen, M_PI_2, vscreen.statusbar.height, 0);
         else
-            d = draw_rotate(ctx, phys_screen, - M_PI_2, 0, sbar.width);
+            d = draw_rotate(ctx, phys_screen, - M_PI_2, 0, vscreen.statusbar.width);
         XCopyArea(awesomeconf->display, d,
-                  sbar.window,
+                  vscreen.statusbar.window,
                   DefaultGC(awesomeconf->display, phys_screen), 0, 0,
-                  sbar.height,
-                  sbar.width, 0, 0);
+                  vscreen.statusbar.height,
+                  vscreen.statusbar.width, 0, 0);
         XFreePixmap(awesomeconf->display, d);
     }
     else
         XCopyArea(awesomeconf->display, ctx->drawable,
-                  sbar.window,
+                  vscreen.statusbar.window,
                   DefaultGC(awesomeconf->display, phys_screen), 0, 0,
-                  sbar.width, sbar.height, 0, 0);
+                  vscreen.statusbar.width, vscreen.statusbar.height, 0, 0);
+
     draw_free_context(ctx);
     XSync(awesomeconf->display, False);
 }