#include "../../lv_examples.h"
#if LV_USE_SCALE && LV_BUILD_EXAMPLES

#include "../../../lvgl_private.h" /*To expose the fields of lv_draw_task_t*/

static void draw_event_cb(lv_event_t * e)
{
    lv_obj_t * obj = lv_event_get_target_obj(e);
    lv_draw_task_t * draw_task = lv_event_get_draw_task(e);
    lv_draw_dsc_base_t * base_dsc = (lv_draw_dsc_base_t *)lv_draw_task_get_draw_dsc(draw_task);
    lv_draw_label_dsc_t * label_draw_dsc = lv_draw_task_get_label_dsc(draw_task);
    if(base_dsc->part == LV_PART_INDICATOR) {
        if(label_draw_dsc) {
            const lv_color_t color_idx[7] = {
                lv_palette_main(LV_PALETTE_RED),
                lv_palette_main(LV_PALETTE_ORANGE),
                lv_palette_main(LV_PALETTE_YELLOW),
                lv_palette_main(LV_PALETTE_GREEN),
                lv_palette_main(LV_PALETTE_CYAN),
                lv_palette_main(LV_PALETTE_BLUE),
                lv_palette_main(LV_PALETTE_PURPLE),
            };
            uint32_t major_tick = lv_scale_get_major_tick_every(obj);
            label_draw_dsc->color = color_idx[base_dsc->id1 / major_tick];

            /*Free the previously allocated text if needed*/
            if(label_draw_dsc->text_local) lv_free((void *)label_draw_dsc->text);

            /*Malloc the text and set text_local as 1 to make LVGL automatically free the text.
             * (Local texts are malloc'd internally by LVGL. Mimic this behavior here too)*/
            char tmp_buffer[20] = {0}; /* Big enough buffer */
            lv_snprintf(tmp_buffer, sizeof(tmp_buffer), "%.1f", (double)base_dsc->id2);
            label_draw_dsc->text = lv_strdup(tmp_buffer);
            label_draw_dsc->text_local = 1;

            lv_point_t size;
            lv_text_get_size(&size, label_draw_dsc->text, label_draw_dsc->font, 0, 0, 1000, LV_TEXT_FLAG_NONE);
            int32_t new_w = size.x;
            int32_t old_w = lv_area_get_width(&draw_task->area);

            /* Distribute the new size equally on both sides */
            draw_task->area.x1 -= (new_w - old_w) / 2;
            draw_task->area.x2 += ((new_w - old_w) + 1) / 2;  /* +1 for rounding */

        }
    }
}

/**
 * Customizing scale major tick label color with `LV_EVENT_DRAW_TASK_ADDED` event
 */
void lv_example_scale_7(void)
{
    lv_obj_t * scale = lv_scale_create(lv_screen_active());
    lv_obj_set_size(scale, lv_pct(80), 100);
    lv_scale_set_mode(scale, LV_SCALE_MODE_HORIZONTAL_BOTTOM);
    lv_obj_center(scale);

    lv_scale_set_label_show(scale, true);

    lv_scale_set_total_tick_count(scale, 31);
    lv_scale_set_major_tick_every(scale, 5);

    lv_obj_set_style_length(scale, 5, LV_PART_ITEMS);
    lv_obj_set_style_length(scale, 10, LV_PART_INDICATOR);
    lv_scale_set_range(scale, 10, 40);

    lv_obj_add_event_cb(scale, draw_event_cb, LV_EVENT_DRAW_TASK_ADDED, NULL);
    lv_obj_add_flag(scale, LV_OBJ_FLAG_SEND_DRAW_TASK_EVENTS);
}

#endif
