MODULE Desktop;
    IMPORT OS;

    VAR desktopRunning: CHAR;
        desktopWindow: ARRAY WINDOW_STRUCT_SIZE OF CHAR;
        desktopIcons: ARRAY 5 OF Fox32OSButtonWidget;
        desktopDiskIcon: ARRAY 4096 OF CHAR;

    PROCEDURE DesktopMain(hasIcons: CHAR; iconsResPtr: PTR;);
    VAR tempDskIconResPtr: PTR;
    BEGIN
        desktopRunning := 1;

        (* if icons.res was loaded, then pull the `dsk` resource from it *)
        IF hasIcons THEN
            tempDskIconResPtr := get_resource(iconsResPtr, "dsk", 4096);
            IF tempDskIconResPtr THEN
                copy_memory_bytes(tempDskIconResPtr, PTROF(desktopDiskIcon), 4096);
                free_memory(tempDskIconResPtr);
            END;
        END;

        (* set up the desktop icon widgets *)
        SetupDesktopIconStructs();

        (* create the window and make it fully transparent, mark it as "always background", and draw the icons to it *)
        new_window(PTROF(desktopWindow), "Desktop", 640, 448, 0, 16, 0, PTROF(desktopIcons));
        fill_overlay(000000000H, get_window_overlay_number(PTROF(desktopWindow)));
        set_window_flags(000000001H, PTROF(desktopWindow));
        DrawDesktopIcons(PTROF(desktopWindow));

        WHILE desktopRunning DO
            GetNextWindowEvent(PTROF(desktopWindow));

            (* mouse click event *)
            IF eventArgs[0] = PTROF(EVENT_TYPE_MOUSE_CLICK) THEN
                handle_widget_click(PTROF(desktopWindow), eventArgs[1], eventArgs[2]);

            (* button click event *)
            ELSIF eventArgs[0] = PTROF(EVENT_TYPE_BUTTON_CLICK) THEN
                HandleDesktopIconClick(eventArgs[1]);
            END;

            save_state_and_yield_task();
        END;
    END;

    PROCEDURE HandleDesktopIconClick(buttonId: INT;);
    VAR i, x, y, w, h: INT;
        icon: POINTER TO Fox32OSButtonWidget;
    BEGIN
        (* draw the expanding box animation *)
        i := 0;
        icon := PTROF(desktopIcons[buttonId]);
        WHILE i <| 16 DO
            x := RSH(icon^.x *| (16 - i) + 64 *| i, 4);
            y := RSH(icon^.y *| (16 - i) + 64 *| i, 4);
            w := RSH(32 *| (16 - i) + 384 *| i, 4);
            h := RSH(32 *| (16 - i) + 192 *| i, 4);
            DrawWireframeBox(get_window_overlay_number(PTROF(desktopWindow)), x, y, w, h, 020F0F0F0H);
            sleep_task(10);
            draw_filled_rectangle_to_overlay(x, y, w, h, 0, get_window_overlay_number(PTROF(desktopWindow)));
            i := i + 1;
        END;

        (* redraw the icons *)
        DrawDesktopIcons(PTROF(desktopWindow));

        (* launch a new instance of Fetcher *)
        IF launch_fxf_from_disk("fetcher.fxf", get_boot_disk_id(), 0FFFFFFFFH, buttonId, icon^.x, icon^.y, PTROF(desktopWindow)) = 0FFFFFFFFH THEN
            new_messagebox("Failed to start new", "instance of fetcher.fxf", 0, 64, 64, 200);
        END;
    END;

    PROCEDURE DrawDesktopIcons(desktopWin: PTR;);
    VAR i, y, overlay: INT;
    BEGIN
        IF desktopWin = 0 THEN RETURN(); END;

        (* draw the buttons themselves *)
        draw_widgets_to_window(desktopWin);

        (* set the tilemap and draw the icons! *)
        set_tilemap(PTROF(desktopDiskIcon), 32, 32);
        overlay := get_window_overlay_number(desktopWin);
        i := 5;
        y := 16;
        WHILE i DO
            draw_tile_to_overlay(0, 592, y, overlay);
            y := y + 64;
            i := i - 1;
        END;
    END;

    PROCEDURE SetupDesktopIconStructs();
    VAR desktopIcon: POINTER TO Fox32OSButtonWidget;
        prevDesktopIcon: POINTER TO Fox32OSButtonWidget;
    BEGIN
        desktopIcon := PTROF(desktopIcons[0]);
        desktopIcon^.type := WIDGET_TYPE_BUTTON;
        desktopIcon^.next := PTROF(desktopIcons[1]);
        desktopIcon^.id := 0;
        desktopIcon^.text := "Disk 0";
        desktopIcon^.fgColor := 0FF000000H;
        desktopIcon^.bgColor := 0FFFFFFFFH;
        desktopIcon^.width := 32;
        desktopIcon^.height := 32 + 16;
        desktopIcon^.x := 592;
        desktopIcon^.y := 16;

        prevDesktopIcon := desktopIcon;
        desktopIcon := PTROF(desktopIcons[1]);
        desktopIcon^.type := WIDGET_TYPE_BUTTON;
        desktopIcon^.next := PTROF(desktopIcons[2]);
        desktopIcon^.id := 1;
        desktopIcon^.text := "Disk 1";
        desktopIcon^.fgColor := 0FF000000H;
        desktopIcon^.bgColor := 0FFFFFFFFH;
        desktopIcon^.width := 32;
        desktopIcon^.height := 32 + 16;
        desktopIcon^.x := 592;
        desktopIcon^.y := prevDesktopIcon^.y + 32 + 32;

        prevDesktopIcon := desktopIcon;
        desktopIcon := PTROF(desktopIcons[2]);
        desktopIcon^.type := WIDGET_TYPE_BUTTON;
        desktopIcon^.next := PTROF(desktopIcons[3]);
        desktopIcon^.id := 2;
        desktopIcon^.text := "Disk 2";
        desktopIcon^.fgColor := 0FF000000H;
        desktopIcon^.bgColor := 0FFFFFFFFH;
        desktopIcon^.width := 32;
        desktopIcon^.height := 32 + 16;
        desktopIcon^.x := 592;
        desktopIcon^.y := prevDesktopIcon^.y + 32 + 32;

        prevDesktopIcon := desktopIcon;
        desktopIcon := PTROF(desktopIcons[3]);
        desktopIcon^.type := WIDGET_TYPE_BUTTON;
        desktopIcon^.next := PTROF(desktopIcons[4]);
        desktopIcon^.id := 3;
        desktopIcon^.text := "Disk 3";
        desktopIcon^.fgColor := 0FF000000H;
        desktopIcon^.bgColor := 0FFFFFFFFH;
        desktopIcon^.width := 32;
        desktopIcon^.height := 32 + 16;
        desktopIcon^.x := 592;
        desktopIcon^.y := prevDesktopIcon^.y + 32 + 32;

        prevDesktopIcon := desktopIcon;
        desktopIcon := PTROF(desktopIcons[4]);
        desktopIcon^.type := WIDGET_TYPE_BUTTON;
        desktopIcon^.next := 0;
        desktopIcon^.id := 4;
        desktopIcon^.text := "Disk 4";
        desktopIcon^.fgColor := 0FF000000H;
        desktopIcon^.bgColor := 0FFFFFFFFH;
        desktopIcon^.width := 32;
        desktopIcon^.height := 32 + 16;
        desktopIcon^.x := 592;
        desktopIcon^.y := prevDesktopIcon^.y + 32 + 32;
    END;
END.