MODULE Browser;
    IMPORT OS, About, Desktop;

    VAR browserRunning: CHAR;
        browserWindow: ARRAY WINDOW_STRUCT_SIZE OF CHAR;
        browserIcons: ARRAY 12 OF Fox32OSButtonWidget;
        browserPage: INT;
        browserNumberOfPages: INT;
        browserNextPageButton: Fox32OSButtonWidget;
        browserPrevPageButton: Fox32OSButtonWidget;
        browserDiskId: INT;
        browserFileList: ARRAY 341 OF CHAR;
        browserHasIcons: CHAR;
        browserIconsResPtr: PTR;

    EXTERN browserMenuItemsRoot: POINTER TO CHAR;
    EXTERN browserFileListFriendly: ARRAY 12 OF POINTER TO CHAR;

    PROCEDURE BrowserMain(diskId, iconX, iconY: INT; desktopWin: PTR; hasIcons: CHAR; iconsResPtr: PTR;);
    VAR tempDskIconResPtr: PTR;
    BEGIN
        (* first, before we do anything, check to make sure the selected disk is available *)
        IF diskId >| 4 THEN
            new_messagebox(0, "Invalid disk ID!", 0, 128, 128, 144);
            end_current_task();
        ELSIF diskId = 4 THEN
            IF IsRomDiskAvailable() = 0 THEN
                new_messagebox(0, "ROM disk not available!", 0, 128, 128, 200);
                end_current_task();
            END;
        ELSE
            IF PortIn(080001000H OR diskId) = 0 THEN
                new_messagebox(0, "Disk not inserted!", 0, 128, 128, 160);
                end_current_task();
            END;
        END;

        browserRunning := 1;
        browserPage := 0;
        browserDiskId := diskId;
        browserHasIcons := 0;
        browserIconsResPtr := iconsResPtr;

        (* if icons.res was loaded, then pull the `dsk` resource from it *)
        IF hasIcons THEN
            tempDskIconResPtr := get_resource(browserIconsResPtr, "dsk", 4096);
            IF tempDskIconResPtr THEN
                copy_memory_bytes(tempDskIconResPtr, PTROF(desktopDiskIcon), 4096);
                free_memory(tempDskIconResPtr);
            END;
            browserHasIcons := 1;
        END;

        (* create the window and draw its initial contents *)
        new_window(PTROF(browserWindow), "Fetcher", 384, 192, 64, 64, PTROF(browserMenuItemsRoot), PTROF(browserIcons));
        DrawBrowserWindow();

        WHILE browserRunning DO
            GetNextWindowEvent(PTROF(browserWindow));

            (* mouse click event *)
            IF eventArgs[0] = PTROF(EVENT_TYPE_MOUSE_CLICK) THEN
                IF (eventArgs[1] <| 8) & (eventArgs[2] <| 16) THEN
                    destroy_window(PTROF(browserWindow));
                    browserRunning := 0;
                    QuitAnimation(iconX, iconY, desktopWin);
                ELSIF eventArgs[2] <| 16 THEN
                    start_dragging_window(PTROF(browserWindow));
                END;
                handle_widget_click(PTROF(browserWindow), eventArgs[1], eventArgs[2]);

            (* menu bar click event *)
            ELSIF eventArgs[0] = PTROF(EVENT_TYPE_MENU_BAR_CLICK) THEN
                menu_bar_click_event(PTROF(browserMenuItemsRoot));

            (* menu update event *)
            ELSIF eventArgs[0] = PTROF(EVENT_TYPE_MENU_UPDATE) THEN
                menu_update_event();

            (* menu click event *)
            ELSIF eventArgs[0] = PTROF(EVENT_TYPE_MENU_CLICK) THEN
                MenuClickEvent(eventArgs[2], eventArgs[3]);

            (* menu ack event *)
            ELSIF eventArgs[0] = PTROF(EVENT_TYPE_MENU_ACK) THEN
                close_menu(PTROF(browserMenuItemsRoot));

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

            save_state_and_yield_task();
        END;
    END;

    PROCEDURE HandleIconClick(buttonId: INT;);
    BEGIN
        IF buttonId = 128 THEN
            (* next page button *)
            IncrementBrowserPage();
        ELSIF buttonId = 129 THEN
            (* previous page button *)
            DecrementBrowserPage();
        ELSE
            (* an icon was clicked! *)
            LaunchFromIcon(buttonId);
        END;
    END;

    PROCEDURE MenuClickEvent(rootIndex, itemIndex: INT;);
    BEGIN
        IF rootIndex = 0 THEN
            (* System menu *)
            IF itemIndex = 0 THEN
                (* About fox32os *)

                (* DIRTY HACK WARNING!!! *)
                close_menu(PTROF(browserMenuItemsRoot));

                AboutMain();
            END;
        END;
    END;

    PROCEDURE DrawBrowserWindow();
    BEGIN
        fill_window(0FFFFFFFFH, PTROF(browserWindow));
        SetupBrowserIconStructs();
        draw_widgets_to_window(PTROF(browserWindow));
        IF browserHasIcons THEN
            DrawBrowserIcons();
        END;
    END;

    PROCEDURE DrawBrowserIcons();
    VAR i: INT;
        icon: POINTER TO Fox32OSButtonWidget;
        tempFileIconResPtr: PTR;
        overlay: INT;
    BEGIN
        i := 0;
        overlay := get_window_overlay_number(PTROF(browserWindow));
        WHILE i <| 12 DO
            icon := PTROF(browserIcons[i]);
            tempFileIconResPtr := get_resource(browserIconsResPtr, icon^.text + string_length(icon^.text) - 3, 4096);
            IF tempFileIconResPtr THEN
                set_tilemap(tempFileIconResPtr, 32, 32);
                draw_tile_to_overlay(0, icon^.x, icon^.y, overlay);
                free_memory(tempFileIconResPtr);
            END;
            i := i + 1;
        END;
    END;

    PROCEDURE SetupBrowserIconStructs();
    VAR i, x, y, numberOfFiles: INT;
        icon: POINTER TO Fox32OSButtonWidget;
    BEGIN
        (* get a list of files *)
        numberOfFiles := ryfs_get_file_list(PTROF(browserFileList), browserDiskId);
        browserNumberOfPages := numberOfFiles / 12;
        ConvertFileNames(numberOfFiles);

        i := 0;
        WHILE i <| 12 DO
            x := ((i MOD 4) * 96) + 32;
            y := ((i / 4) * 64) + 24;
            icon := PTROF(browserIcons[i]);

            icon^.type := WIDGET_TYPE_BUTTON;
            IF i = 11 THEN icon^.next := PTROF(browserNextPageButton);
            ELSE icon^.next := PTROF(browserIcons[i + 1]); END;
            icon^.id := i;
            icon^.text := browserFileListFriendly[i];
            icon^.fgColor := 0FF000000H;
            icon^.bgColor := 0FFDDDDDDH;
            icon^.width := 32;
            icon^.height := 32 + 16;
            icon^.x := x;
            icon^.y := y;

            i := i + 1;
        END;

        browserNextPageButton.type := WIDGET_TYPE_BUTTON;
        browserNextPageButton.next := PTROF(browserPrevPageButton);
        browserNextPageButton.id := 128;
        browserNextPageButton.text := ">";
        browserNextPageButton.fgColor := 0FF000000H;
        browserNextPageButton.bgColor := 0FFDDDDDDH;
        browserNextPageButton.width := 16;
        browserNextPageButton.height := 16;
        browserNextPageButton.x := 368;
        browserNextPageButton.y := 16;

        browserPrevPageButton.type := WIDGET_TYPE_BUTTON;
        browserPrevPageButton.next := 0;
        browserPrevPageButton.id := 129;
        browserPrevPageButton.text := "<";
        browserPrevPageButton.fgColor := 0FF000000H;
        browserPrevPageButton.bgColor := 0FFDDDDDDH;
        browserPrevPageButton.width := 16;
        browserPrevPageButton.height := 16;
        browserPrevPageButton.x := 0;
        browserPrevPageButton.y := 16;
    END;

    PROCEDURE IncrementBrowserPage();
    BEGIN
        IF browserPage <| browserNumberOfPages THEN
            browserPage := browserPage + 1;
        END;
        DrawBrowserWindow();
    END;

    PROCEDURE DecrementBrowserPage();
    BEGIN
        IF browserPage >| 0 THEN
            browserPage := browserPage - 1;
        END;
        DrawBrowserWindow();
    END;

    PROCEDURE LaunchFromIcon(buttonId: INT;);
    VAR icon: POINTER TO Fox32OSButtonWidget;
    BEGIN
        icon := PTROF(browserIcons[buttonId]);
        launch_fxf_from_disk(icon^.text, browserDiskId, 0, 0, 0, 0, 0);
    END;

    PROCEDURE ConvertFileNames(numberOfFiles: INT;);
    VAR i, j, numberOfFilesLeft: INT;
    BEGIN
        (* fill all filenames with "<empty>", 0, 0, 0, 0, 0 *)
        i := 12;
        WHILE i DO
            copy_memory_bytes("<empty>\0\0\0\0\0", browserFileListFriendly[i - 1], 12);
            i := i - 1;
        END;

        i := 0;
        numberOfFilesLeft := numberOfFiles - (browserPage * 12);
        IF numberOfFilesLeft >| 12 THEN
            numberOfFilesLeft := 12;
        END;
        WHILE i <| numberOfFilesLeft DO
            (* copy the first 8 characters (the actual name of the file) *)
            copy_memory_bytes(PTROF(browserFileList) + (browserPage * 11 * 12) + (i * 11), browserFileListFriendly[i], 8);

            (* find the first space in the name *)
            j := 7;
            WHILE j DO
                IF GETCHAR(PTROF(browserFileList) + (browserPage * 11 * 12) + (i * 11) + j) # 32 THEN
                    BREAK();
                END;
                j := j - 1;
            END;
            j := j + 1;

            (* j now equals the index of where the file name ends and the extension begins *)
            PUTCHAR(browserFileListFriendly[i] + j, 46);
            copy_memory_bytes(PTROF(browserFileList) + (browserPage * 11 * 12) + (i * 11) + 8, browserFileListFriendly[i] + j + 1, 3);
            PUTCHAR(browserFileListFriendly[i] + j + 4, 0);

            i := i + 1;
        END;
    END;

    PROCEDURE QuitAnimation(iconX, iconY: INT; desktopWin: PTR;);
    VAR i, x, y, w, h: INT;
    BEGIN
        IF desktopWin # 0 THEN
            (* draw the retracting box animation *)
            i := 0;
            WHILE i < 16 DO
                x := RSH(GETSHORT(PTROF(browserWindow) + 20) *| (16 - i) + iconX *| i, 4);
                y := RSH(GETSHORT(PTROF(browserWindow) + 22) *| (16 - i) + iconY *| i, 4);
                w := RSH(384 *| (16 - i) + 32 *| i, 4);
                h := RSH(192 *| (16 - i) + 32 *| i, 4);
                DrawWireframeBox(get_window_overlay_number(desktopWin), x, y, w, h, 020F0F0F0H);
                sleep_task(10);
                draw_filled_rectangle_to_overlay(x, y, w, h, 0, get_window_overlay_number(desktopWin));
                i := i + 1;
            END;
            DrawDesktopIcons(desktopWin);
        END;
    END;
END.