/*
 * File      : listctrl.c
 * This file is part of RTGUI in RT-Thread RTOS
 * COPYRIGHT (C) 2010, RT-Thread Development Team
 *
 * The license and distribution terms for this file may be
 * found in the file LICENSE in this distribution or at
 * http://www.rt-thread.org/license/LICENSE
 *
 * Change Logs:
 * Date           Author       Notes
 * 2010-01-06     Bernard      first version
 */

#include <rtgui/rtgui_theme.h>
#include <rtgui/widgets/listctrl.h>

static void rtgui_listctrl_update_current(struct rtgui_listctrl *ctrl, rt_uint16_t old_item);

static void _rtgui_listctrl_constructor(struct rtgui_listctrl *ctrl)
{
    /* set default widget rect and set event handler */
    rtgui_object_set_event_handler(RTGUI_OBJECT(ctrl), rtgui_listctrl_event_handler);

    RTGUI_WIDGET(ctrl)->flag |= RTGUI_WIDGET_FLAG_FOCUSABLE;

    ctrl->current_item = -1;
    ctrl->item_height = rtgui_theme_get_selected_height();
    ctrl->items_count = 0;
    ctrl->page_items = 0;
    ctrl->on_item = 0;
    ctrl->on_item_draw = RT_NULL;

    RTGUI_WIDGET_BACKGROUND(ctrl) = white;
    RTGUI_WIDGET_TEXTALIGN(ctrl) = RTGUI_ALIGN_CENTER_VERTICAL;
}

DEFINE_CLASS_TYPE(listctrl, "listctrl",
                  RTGUI_WIDGET_TYPE,
                  _rtgui_listctrl_constructor,
                  RT_NULL,
                  sizeof(struct rtgui_listctrl));

static void _rtgui_listctrl_get_rect(struct rtgui_listctrl *ctrl, rtgui_rect_t *rect)
{
    rtgui_widget_get_rect(RTGUI_WIDGET(ctrl), rect);
    if (ctrl->items_count > rtgui_rect_height(*rect) / ctrl->item_height)
    {
        rect->x2 = rect->x2 - 8;
    }
}

static void _rtgui_listctrl_get_scrollbar_rect(struct rtgui_listctrl *ctrl, rtgui_rect_t *rect)
{
    rtgui_widget_get_rect(RTGUI_WIDGET(ctrl), rect);
    if (ctrl->items_count > rtgui_rect_height(*rect) / ctrl->item_height)
    {
        rect->x1 = rect->x2 - 8;
    }
    else
    {
        /* no scrollbar */
        rt_memset(rect, 0, sizeof(rtgui_rect_t));
    }
}

static void _rtgui_listctrl_scrollbar_ondraw(struct rtgui_listctrl *ctrl, struct rtgui_dc *dc)
{
    rtgui_rect_t rect;
    rt_uint32_t height, y1;

    /* get scrollbar rect */
    _rtgui_listctrl_get_scrollbar_rect(ctrl, &rect);
    if (rtgui_rect_is_empty(&rect) == RT_TRUE) return;

    rtgui_dc_fill_rect(dc, &rect);

    height = rtgui_rect_height(rect);
    height = height / ((ctrl->items_count + (ctrl->page_items - 1)) / ctrl->page_items);
    y1 = (ctrl->current_item / ctrl->page_items) * height;

    rect.y1 = rect.y1 + y1;
    rect.y2 = rect.y1 + height;
    rect.x1 -= 3;
    rtgui_theme_draw_selected(dc, &rect);
}

static void _rtgui_listctrl_scrollbar_onmouse(struct rtgui_listctrl *ctrl, struct rtgui_event_mouse *mouse)
{
    rtgui_rect_t rect;
    rt_uint32_t height, y1;
    rt_uint16_t old_item;

    /* get scrollbar rect */
    _rtgui_listctrl_get_scrollbar_rect(ctrl, &rect);
    height = rtgui_rect_height(rect);
    height = height / ((ctrl->items_count + (ctrl->page_items - 1)) / ctrl->page_items);
    y1 = (ctrl->current_item / ctrl->page_items) * height;

    rect.y1 = rect.y1 + y1;
    rect.y2 = rect.y1 + height;
    rtgui_widget_rect_to_device(RTGUI_WIDGET(ctrl), &rect);

    old_item = ctrl->current_item;
    if (mouse->y < rect.y1)
    {
        if (ctrl->current_item - ctrl->page_items >= 0)
            rtgui_listctrl_set_current_item(ctrl, ctrl->current_item - ctrl->page_items);
        else
            rtgui_listctrl_update_current(ctrl, old_item);
    }
    else if (mouse->y > rect.y2)
    {
        rt_uint16_t new_item;
        if (ctrl->current_item + ctrl->page_items < ctrl->items_count - 1)
            new_item = ctrl->current_item + ctrl->page_items;
        else
            new_item = ((ctrl->current_item / ctrl->page_items) + 1) * ctrl->page_items;
        rtgui_listctrl_set_current_item(ctrl, new_item);
    }
}

static void _rtgui_listctrl_ondraw(struct rtgui_listctrl *ctrl)
{
    struct rtgui_rect rect, item_rect;
    struct rtgui_dc *dc;
    rt_uint16_t page_index, index;

    dc = rtgui_dc_begin_drawing(RTGUI_WIDGET(ctrl));
    if (dc == RT_NULL) return;

    _rtgui_listctrl_get_rect(ctrl, &rect);
    rtgui_dc_fill_rect(dc, &rect);

    rect.x2 -= 1;
    rect.y2 -= 1;

    /* get item base rect */
    item_rect = rect;
    item_rect.x1 += 1;
    item_rect.x2 -= 1;
    item_rect.y1 += 2;
    item_rect.y2 = item_rect.y1 + (2 + ctrl->item_height);

    /* get current page */
    page_index = (ctrl->current_item / ctrl->page_items) * ctrl->page_items;
    for (index = 0; index < ctrl->page_items; index ++)
    {
        if (page_index + index >= ctrl->items_count) break;

        if (page_index + index == ctrl->current_item)
        {
            rtgui_theme_draw_selected(dc, &item_rect);
        }

        if (ctrl->on_item_draw != RT_NULL)
        {
            ctrl->on_item_draw(ctrl, dc, &item_rect, page_index + index);
        }

        /* move to next item position */
        item_rect.y1 += (ctrl->item_height + 2);
        item_rect.y2 += (ctrl->item_height + 2);
    }

    /* draw scrollbar */
    _rtgui_listctrl_scrollbar_ondraw(ctrl, dc);
    rtgui_dc_end_drawing(dc);
}

static void rtgui_listctrl_update_current(struct rtgui_listctrl *ctrl, rt_uint16_t old_item)
{
    struct rtgui_dc *dc;
    rtgui_rect_t rect, item_rect;

    if (old_item / ctrl->page_items != ctrl->current_item / ctrl->page_items)
    {
        /* it's not a same page, update all */
        rtgui_widget_update(RTGUI_WIDGET(ctrl));
        return;
    }

    dc = rtgui_dc_begin_drawing(RTGUI_WIDGET(ctrl));
    if (dc == RT_NULL) return;

    _rtgui_listctrl_get_rect(ctrl, &rect);
    rect.x2 -= 1;
    rect.y2 -= 1;

    item_rect = rect;
    /* get old item's rect */
    item_rect.x1 += 1;
    item_rect.x2 -= 1;
    item_rect.y1 += 2;
    item_rect.y1 += (old_item % ctrl->page_items) * (2 + ctrl->item_height);
    item_rect.y2 = item_rect.y1 + (2 + ctrl->item_height);

    /* draw old item */
    rtgui_dc_fill_rect(dc, &item_rect);
    if (ctrl->on_item_draw != RT_NULL)
        ctrl->on_item_draw(ctrl, dc, &item_rect, old_item);

    /* draw current item */
    item_rect = rect;
    /* get current item's rect */
    item_rect.x1 += 1;
    item_rect.x2 -= 1;
    item_rect.y1 += 2;
    item_rect.y1 += (ctrl->current_item % ctrl->page_items) * (2 + ctrl->item_height);
    item_rect.y2 = item_rect.y1 + (2 + ctrl->item_height);

    /* draw current item */
    rtgui_theme_draw_selected(dc, &item_rect);
    if (ctrl->on_item_draw != RT_NULL)
        ctrl->on_item_draw(ctrl, dc, &item_rect, ctrl->current_item);

    rtgui_dc_end_drawing(dc);
}

rt_bool_t rtgui_listctrl_event_handler(struct rtgui_object *object, struct rtgui_event *event)
{
    struct rtgui_listctrl *ctrl;
    RTGUI_WIDGET_EVENT_HANDLER_PREPARE

    ctrl = RTGUI_LISTCTRL(object);
    switch (event->type)
    {
    case RTGUI_EVENT_PAINT:
        _rtgui_listctrl_ondraw(ctrl);
        return RT_FALSE;

    case RTGUI_EVENT_RESIZE:
    {
        struct rtgui_event_resize *resize;

        resize = (struct rtgui_event_resize *)event;

        /* recalculate page items */
        ctrl->page_items = resize->h  / (2 + ctrl->item_height);
    }
    break;

    case RTGUI_EVENT_MOUSE_BUTTON:
    {
        rtgui_rect_t rect;
        struct rtgui_event_mouse *emouse;

        emouse = (struct rtgui_event_mouse *)event;

        /* get scrollbar rect */
        _rtgui_listctrl_get_scrollbar_rect(ctrl, &rect);
        rtgui_widget_rect_to_device(RTGUI_WIDGET(ctrl), &rect);
        if (rtgui_rect_contains_point(&rect, emouse->x, emouse->y) == RT_EOK)
        {
            _rtgui_listctrl_scrollbar_onmouse(ctrl, emouse);
            return RT_TRUE;
        }

        /* calculate selected item */

        /* get physical extent information */
        _rtgui_listctrl_get_rect(ctrl, &rect);
        rtgui_widget_rect_to_device(widget, &rect);

        if ((rtgui_rect_contains_point(&rect, emouse->x, emouse->y) == RT_EOK) &&
                (ctrl->items_count > 0))
        {
            rt_uint16_t index;
            index = (emouse->y - rect.y1) / (2 + ctrl->item_height);

            /* set focus */
            rtgui_widget_focus(widget);
            {
                struct rtgui_rect rect;
                struct rtgui_dc *dc;

                dc = rtgui_dc_begin_drawing(RTGUI_WIDGET(ctrl));
                if (dc != RT_NULL)
                {
                    /* get widget rect */
                    rtgui_widget_get_rect(RTGUI_WIDGET(ctrl), &rect);
                    /* update focus border */
                    rect.x2 -= 1;
                    rect.y2 -= 1;
                    rtgui_dc_end_drawing(dc);
                }
            }

            if ((index < ctrl->page_items) &&
                    (ctrl->current_item / ctrl->page_items)* ctrl->page_items + index < ctrl->items_count)
            {
                if (emouse->button & RTGUI_MOUSE_BUTTON_DOWN)
                {
                    rtgui_listctrl_set_current_item(ctrl,
                            (ctrl->current_item / ctrl->page_items) * ctrl->page_items + index);
                }
            }
        }

        return RT_TRUE;
    }

    case RTGUI_EVENT_KBD:
    {
        struct rtgui_event_kbd *ekbd = (struct rtgui_event_kbd *)event;
        if ((ekbd->type == RTGUI_KEYDOWN) && (ctrl->items_count > 0))
        {
            switch (ekbd->key)
            {
            case RTGUIK_LEFT:
                if (ctrl->current_item - ctrl->page_items >= 0)
                    rtgui_listctrl_set_current_item(ctrl, ctrl->current_item - ctrl->page_items);
                return RT_TRUE;

            case RTGUIK_UP:
                if (ctrl->current_item > 0)
                    rtgui_listctrl_set_current_item(ctrl, ctrl->current_item-1);
                return RT_TRUE;

            case RTGUIK_RIGHT:
                {
                    rt_uint16_t new_item = ctrl->items_count;
                    if (ctrl->current_item + ctrl->page_items < ctrl->items_count - 1)
                        new_item = ctrl->current_item + ctrl->page_items;
                    else
                    {
                        if ((((ctrl->current_item / ctrl->page_items) + 1) * ctrl->page_items)
                                < ctrl->items_count - 1)
                            new_item = ((ctrl->current_item / ctrl->page_items) + 1) * ctrl->page_items;
                    }
                    rtgui_listctrl_set_current_item(ctrl, new_item);
                }
                return RT_TRUE;

            case RTGUIK_DOWN:
                if (ctrl->current_item < ctrl->items_count - 1)
                    rtgui_listctrl_set_current_item(ctrl, ctrl->current_item+1);
                return RT_TRUE;

            case RTGUIK_RETURN:
                if (ctrl->on_item != RT_NULL)
                {
                    return ctrl->on_item(RTGUI_OBJECT(ctrl), RT_NULL);
                }
                return RT_FALSE;

            default:
                break;
            }
        }
    }
    return RT_FALSE;
    default:
    /* use ctrl event handler */
    return rtgui_widget_event_handler(RTGUI_OBJECT(widget), event);
    }

    return RT_FALSE;
}
RTM_EXPORT(rtgui_listctrl_event_handler);

rtgui_listctrl_t *rtgui_listctrl_create(void *items, rt_uint16_t count, rtgui_rect_t *rect,
                                        rtgui_onitem_draw_t ondraw)
{
    struct rtgui_listctrl *ctrl = RT_NULL;

    ctrl = (struct rtgui_listctrl *) rtgui_widget_create(RTGUI_LISTCTRL_TYPE);
    if (ctrl != RT_NULL)
    {
        ctrl->items = items;
        ctrl->items_count = count;
        ctrl->on_item_draw = ondraw;

        ctrl->page_items = rtgui_rect_height(*rect) / (2 + ctrl->item_height);
        rtgui_widget_set_rect(RTGUI_WIDGET(ctrl), rect);
    }

    return ctrl;
}
RTM_EXPORT(rtgui_listctrl_create);

void rtgui_listctrl_destroy(rtgui_listctrl_t *ctrl)
{
    /* destroy ctrl */
    rtgui_widget_destroy(RTGUI_WIDGET(ctrl));
}
RTM_EXPORT(rtgui_listctrl_destroy);

void rtgui_listctrl_set_onitem(rtgui_listctrl_t *ctrl, rtgui_event_handler_ptr func)
{
    RT_ASSERT(ctrl != RT_NULL);

    ctrl->on_item = func;
}
RTM_EXPORT(rtgui_listctrl_set_onitem);

void rtgui_listctrl_set_items(rtgui_listctrl_t *ctrl, void *items, rt_uint16_t count)
{
    rtgui_rect_t rect;

    ctrl->items = items;
    ctrl->items_count = count;
    ctrl->current_item = 0;

    rtgui_widget_get_rect(RTGUI_WIDGET(ctrl), &rect);
    ctrl->page_items = rtgui_rect_height(rect) / (2 + ctrl->item_height);

    rtgui_widget_update(RTGUI_WIDGET(ctrl));
}
RTM_EXPORT(rtgui_listctrl_set_items);

/**
 * @brief set the selected(current) item of listctrl widget.
 *
 * If the index is greater than items_count, it will have no effect. Otherwise,
 * the item on @param index will be selected and the on_item will be invoked if
 * it has one.
 *
 * @fixme set current to the items which is not in current page won't update
 * the scrollbar.
 */
void rtgui_listctrl_set_current_item(struct rtgui_listctrl *ctrl, rt_uint16_t index)
{
    RT_ASSERT(ctrl);

    if (index >= ctrl->items_count)
        return;

    if (index != ctrl->current_item)
    {
        rt_uint16_t old_item = ctrl->current_item;
        ctrl->current_item = index;
        rtgui_listctrl_update_current(ctrl, old_item);
    }
    if (ctrl->on_item != RT_NULL)
    {
        ctrl->on_item(RTGUI_OBJECT(ctrl), RT_NULL);
    }
}
RTM_EXPORT(rtgui_listctrl_set_current_item);

rt_bool_t rtgui_listctrl_get_item_rect(rtgui_listctrl_t *ctrl, rt_uint16_t item, rtgui_rect_t *item_rect)
{
    if (item < ctrl->items_count)
    {
        rt_uint16_t index;

        /* check whether this item in current page */
        index = (ctrl->current_item / ctrl->page_items) * ctrl->page_items;
        if (index > item || index + ctrl->page_items <= item) return RT_FALSE;

        rtgui_widget_get_extent(RTGUI_WIDGET(ctrl), item_rect);
        item_rect->y1 -= 2;
        item_rect->y1 += (item % ctrl->page_items) * (2 + ctrl->item_height);
        item_rect->y2 = item_rect->y1 + (2 + ctrl->item_height);
        return RT_TRUE;
    }

    return RT_FALSE;
}
RTM_EXPORT(rtgui_listctrl_get_item_rect);

void rtgui_listctrl_set_itemheight(struct rtgui_listctrl *ctrl, int height)
{
    RT_ASSERT(ctrl != RT_NULL);
    if (height <= 0) return;

    ctrl->item_height = height;
    ctrl->page_items = rtgui_rect_height(RTGUI_WIDGET(ctrl)->extent) / (2 + ctrl->item_height);
}
RTM_EXPORT(rtgui_listctrl_set_itemheight);