#include "../../lv_examples.h"

#if LV_USE_LABEL && LV_FONT_MONTSERRAT_24 && LV_USE_CANVAS && LV_BUILD_EXAMPLES && LV_DRAW_SW_COMPLEX

#define MASK_WIDTH 150
#define MASK_HEIGHT 60

static void generate_mask(lv_draw_buf_t * mask, int32_t w, int32_t h, const char * txt)
{
    /*Create a "8 bit alpha" canvas and clear it*/
    lv_obj_t * canvas = lv_canvas_create(lv_screen_active());
    lv_canvas_set_draw_buf(canvas, mask);
    lv_canvas_fill_bg(canvas, lv_color_black(), LV_OPA_TRANSP);

    lv_layer_t layer;
    lv_canvas_init_layer(canvas, &layer);

    /*Draw a label to the canvas. The result "image" will be used as mask*/
    lv_draw_label_dsc_t label_dsc;
    lv_draw_label_dsc_init(&label_dsc);
    label_dsc.color = lv_color_white();
    label_dsc.align = LV_TEXT_ALIGN_CENTER;
    label_dsc.text = txt;
    label_dsc.font = &lv_font_montserrat_24;
    lv_area_t a = {0, 0, w - 1, h - 1};
    lv_draw_label(&layer, &label_dsc, &a);

    lv_canvas_finish_layer(canvas, &layer);

    lv_obj_delete(canvas);
}

/**
 * Draw label with gradient color
 */
void lv_example_label_4(void)
{
    /* Create the mask of a text by drawing it to a canvas*/
    LV_DRAW_BUF_DEFINE_STATIC(mask, MASK_WIDTH, MASK_HEIGHT, LV_COLOR_FORMAT_L8);
    LV_DRAW_BUF_INIT_STATIC(mask);

    generate_mask(&mask, MASK_WIDTH, MASK_HEIGHT, "Text with gradient");

    /* Create an object from where the text will be masked out.
     * Now it's a rectangle with a gradient but it could be an image too*/
    lv_obj_t * grad = lv_obj_create(lv_screen_active());
    lv_obj_set_size(grad, MASK_WIDTH, MASK_HEIGHT);
    lv_obj_center(grad);
    lv_obj_set_style_bg_color(grad, lv_color_hex(0xff0000), 0);
    lv_obj_set_style_bg_grad_color(grad, lv_color_hex(0x0000ff), 0);
    lv_obj_set_style_bg_grad_dir(grad, LV_GRAD_DIR_HOR, 0);
    lv_obj_set_style_bitmap_mask_src(grad, &mask, 0);
}

#endif