#define BAR_NUM 24

typedef struct {
    int32_t max_value;
    lv_obj_t* chart;
    int32_t data_buf[BAR_NUM];
    lv_obj_t* scale_right;
    int32_t obj_line_x;
} ChartData;

static ChartData chart_data;

/**
 * Adjusts the value `v` to align with the nearest lower multiple of `step_floor_v`.
 * If `v` is less than or equal to 0, it will be set to `step_floor_v`.
 * Otherwise, it will be rounded down to the nearest multiple of `step_floor_v`.
 *
 * @param v The value to be adjusted.
 * @param step_floor_v The step size to align the value to.
 * @return The adjusted value.
 */
static void floor_data_to(int* v, int step_floor_v) {
    if (v == NULL || step_floor_v == 0) {
        // Handle invalid input
        return;
    }
    *v = step_floor_v + (((*v <= 0) ? 0 : (*v - 1)) / step_floor_v) * step_floor_v;
}

/**
 * Scans the buffer `buf` for the maximum value and stores it in `_p_max`.
 * @param buf The data buffer to scan.
 * @param points_cnt The number of data points.
 * @param _p_max Pointer to store the maximum value found.
 */
static void points_scan_max(lv_coord_t* buf, uint32_t points_cnt, lv_coord_t* _p_max) {
    lv_coord_t max_v = LV_COORD_MIN;
    if (_p_max) {
        for (uint32_t i = 0; i < points_cnt; i++) {
            if (buf[i] > max_v) {
                max_v = buf[i];
            }
        }
        *_p_max = max_v;
    }
}

/**
 * Generates random data and stores it in the provided buffer `buf`.
 * @param buf The buffer to store random data.
 * @param cnt The number of random data points to generate.
 * @param max_val The maximum value for random data generation.
 */
static void _generate_random_data(int32_t* buf, uint16_t cnt, int32_t max_val) {
    for (int i = 0; i < cnt; i++) {
        buf[i] = lv_rand(0, max_val);
    }
}

/**
 * Event callback for the "Random" button to generate random data
 * and update the chart and scale.
 */
static void rand_button_cb(lv_event_t* e) {
    // Generate new random data and update chart range
    lv_chart_series_t* ser1 = lv_event_get_user_data(e);
    _generate_random_data(chart_data.data_buf, BAR_NUM, 1000);
    points_scan_max(chart_data.data_buf, BAR_NUM, &chart_data.max_value);
    floor_data_to(&chart_data.max_value, 10);  // Round down max_value to the nearest multiple of 10

    // Update chart's Y-axis range and data series
    lv_chart_set_range(chart_data.chart, LV_CHART_AXIS_PRIMARY_Y, 0, chart_data.max_value);
    lv_chart_set_ext_y_array(chart_data.chart, ser1, chart_data.data_buf);

    // Update the right scale range
    lv_scale_set_range(chart_data.scale_right, 0, chart_data.max_value);
}

/**
 * Event callback for slider value change. Moves the vertical line based on the slider value.
 */
static void slider_event_cb(lv_event_t* e) {
    lv_obj_t* slider = lv_event_get_target_obj(e);
    lv_obj_t* obj_line = lv_event_get_user_data(e);
    lv_area_t chart_coords;
    lv_obj_get_coords(chart_data.chart, &chart_coords);
    int32_t value = lv_slider_get_value(slider);

    // Update line position based on slider value
    lv_obj_set_x(obj_line, chart_data.obj_line_x + value);

    // Simulate press/release event based on line position
    if (chart_data.obj_line_x + value < chart_coords.x2 - 1)
        lv_obj_send_event(chart_data.chart, LV_EVENT_PRESSED, NULL);
    else
        lv_obj_send_event(chart_data.chart, LV_EVENT_RELEASED, NULL);
}

/**
 * Event callback for chart. Handles drawing events and value display.
 */
static void chart_event_cb(lv_event_t* e) {
    lv_event_code_t code = lv_event_get_code(e);
    lv_obj_t* chart = lv_event_get_target(e);
    lv_obj_t* step_value_label = lv_event_get_user_data(e);
    int32_t value = 0;
    int sum = 0;

    if (code == LV_EVENT_DRAW_TASK_ADDED) {
        // Handle custom drawing for pressed points
        lv_draw_task_t* draw_task = lv_event_get_draw_task(e);
        lv_draw_dsc_base_t* base_dsc = lv_draw_task_get_draw_dsc(draw_task);
        if (base_dsc->part == LV_PART_ITEMS && lv_chart_get_pressed_point(chart) == base_dsc->id2) {
            lv_draw_fill_dsc_t* fill_dsc = lv_draw_task_get_draw_dsc(draw_task);
            fill_dsc->color = lv_color_make(100, 187, 93);  // Highlight color
        }
    }
    else if (code == LV_EVENT_PRESSED) {
        int32_t id = lv_chart_get_pressed_point(chart);
        const lv_chart_series_t* ser = lv_chart_get_series_next(chart, NULL);
        int32_t* y_array = lv_chart_get_y_array(chart, ser);
        value = y_array[id];

        // Display individual bar value
        if (value != 0)
            lv_label_set_text_fmt(step_value_label, "%d", value);
    }
    else if (code == LV_EVENT_RELEASED) {
        int32_t id = lv_chart_get_pressed_point(chart);
        const lv_chart_series_t* ser = lv_chart_get_series_next(chart, NULL);
        int32_t* y_array = lv_chart_get_y_array(chart, ser);

        // Calculate and display the sum of all bar values
        for (int i = 0; i < BAR_NUM; i++) {
            sum += y_array[i];
        }
        if (sum != 0)
            lv_label_set_text_fmt(step_value_label, "%d", sum);
    }
}

/**
 * Main function to create a chart with various UI elements.
 */
void lv_example_grid_3(void) {
    // Column and row descriptions for grid layout
    static int32_t col_dsc[] = { LV_GRID_FR(8), LV_GRID_FR(1), LV_GRID_TEMPLATE_LAST };
    static int32_t row_dsc[] = { LV_GRID_FR(1), LV_GRID_FR(1), LV_GRID_FR(8), LV_GRID_FR(1), LV_GRID_FR(1), LV_GRID_TEMPLATE_LAST };

    // Create a container with grid layout
    lv_obj_t* cont = lv_obj_create(lv_screen_active());
    lv_obj_center(cont);              // Center the container
    lv_obj_set_size(cont, 400, 300);  // Set container size
    lv_obj_remove_flag(cont, LV_OBJ_FLAG_SCROLLABLE);
    lv_obj_set_style_pad_left(cont, 20, LV_PART_MAIN);
    lv_obj_set_grid_dsc_array(cont, col_dsc, row_dsc);  // Apply the grid description

    // Create UI elements inside the container
    lv_obj_t* step_title_label = lv_label_create(cont);
    lv_label_set_text(step_title_label, "step value");
    lv_obj_set_grid_cell(step_title_label, LV_GRID_ALIGN_CENTER, 0, 1, LV_GRID_ALIGN_STRETCH, 0, 1);

    lv_obj_t* step_value_label = lv_label_create(cont);
    lv_label_set_text(step_value_label, "--");
    lv_obj_set_grid_cell(step_value_label, LV_GRID_ALIGN_CENTER, 0, 1, LV_GRID_ALIGN_STRETCH, 1, 1);

    // Create a chart with bar type
    chart_data.chart = lv_chart_create(cont);
    lv_chart_set_type(chart_data.chart, LV_CHART_TYPE_BAR);
    lv_chart_set_div_line_count(chart_data.chart, 5, 0);
    lv_obj_set_style_pad_ver(chart_data.chart, 0, LV_PART_MAIN);
    lv_chart_set_point_count(chart_data.chart, BAR_NUM);
    lv_obj_set_style_radius(chart_data.chart, 0, LV_PART_MAIN);
    lv_obj_set_style_border_width(chart_data.chart, 0, LV_PART_MAIN);
    lv_obj_set_grid_cell(chart_data.chart, LV_GRID_ALIGN_STRETCH, 0, 1, LV_GRID_ALIGN_STRETCH, 2, 1);
    lv_chart_series_t* ser1 = lv_chart_add_series(chart_data.chart, lv_color_make(162, 214, 156), LV_CHART_AXIS_PRIMARY_Y);

    // Generate initial random data and set chart range
    _generate_random_data(chart_data.data_buf, BAR_NUM, 1000);
    points_scan_max(chart_data.data_buf, BAR_NUM, &chart_data.max_value);
    floor_data_to(&chart_data.max_value, 10);
    lv_chart_set_range(chart_data.chart, LV_CHART_AXIS_PRIMARY_Y, 0, chart_data.max_value);
    lv_chart_set_ext_y_array(chart_data.chart, ser1, chart_data.data_buf);
    lv_obj_add_event_cb(chart_data.chart, chart_event_cb, LV_EVENT_ALL, step_value_label);
    lv_obj_add_flag(chart_data.chart, LV_OBJ_FLAG_SEND_DRAW_TASK_EVENTS);
    lv_obj_remove_flag(chart_data.chart, LV_OBJ_FLAG_CLICKABLE);

    lv_obj_t* rand_button = lv_button_create(cont);
    lv_obj_set_grid_cell(rand_button, LV_GRID_ALIGN_CENTER, 1, 1, LV_GRID_ALIGN_START, 0, 1);
    lv_obj_set_style_bg_color(rand_button, lv_palette_main(LV_PALETTE_GREEN), LV_PART_MAIN);
    lv_obj_add_event_cb(rand_button, rand_button_cb, LV_EVENT_SHORT_CLICKED, ser1);

    lv_obj_t* rand_label = lv_label_create(rand_button);
    lv_label_set_text(rand_label, "rand");

    // Create scale on the right side
    chart_data.scale_right = lv_scale_create(cont);
    lv_scale_set_mode(chart_data.scale_right, LV_SCALE_MODE_VERTICAL_RIGHT);
    lv_scale_set_total_tick_count(chart_data.scale_right, 5);
    lv_scale_set_major_tick_every(chart_data.scale_right, 1);
    lv_obj_set_style_line_opa(chart_data.scale_right, LV_OPA_TRANSP, LV_PART_MAIN);
    lv_obj_set_style_line_opa(chart_data.scale_right, LV_OPA_TRANSP, LV_PART_INDICATOR);
    lv_obj_set_grid_cell(chart_data.scale_right, LV_GRID_ALIGN_STRETCH, 1, 1, LV_GRID_ALIGN_STRETCH, 2, 1);
    lv_scale_set_range(chart_data.scale_right, 0, chart_data.max_value);

    // Create scale at the bottom (time labels)
    lv_obj_t* scale_bottom = lv_scale_create(cont);
    lv_scale_set_mode(scale_bottom, LV_SCALE_MODE_HORIZONTAL_BOTTOM);
    lv_scale_set_total_tick_count(scale_bottom, 5);
    lv_scale_set_major_tick_every(scale_bottom, 1);
    lv_obj_set_grid_cell(scale_bottom, LV_GRID_ALIGN_STRETCH, 0, 1, LV_GRID_ALIGN_STRETCH, 3, 1);
    lv_obj_set_style_pad_hor(scale_bottom, lv_chart_get_first_point_center_offset(chart_data.chart), LV_PART_MAIN);
    lv_obj_set_style_line_opa(scale_bottom, LV_OPA_TRANSP, LV_PART_MAIN);
    lv_obj_set_style_line_opa(scale_bottom, LV_OPA_TRANSP, LV_PART_INDICATOR);

    static const char* time[] = { "00:00", "06:00", "12:00", "18:00", "24:00", NULL };
    lv_scale_set_text_src(scale_bottom, time);

    // Create slider to move the vertical line
    lv_area_t chart_coords;
    lv_obj_get_coords(chart_data.chart, &chart_coords);

    lv_obj_t* slider = lv_slider_create(cont);
    lv_obj_set_style_bg_opa(slider, LV_OPA_TRANSP, LV_PART_INDICATOR);
    lv_obj_set_style_bg_opa(slider, LV_OPA_TRANSP, LV_PART_MAIN);

    lv_obj_set_style_bg_color(slider, lv_color_make(162, 214, 156), LV_PART_KNOB);
    lv_obj_set_style_pad_left(slider, lv_chart_get_first_point_center_offset(chart_data.chart), LV_PART_MAIN);
    lv_obj_set_grid_cell(slider, LV_GRID_ALIGN_STRETCH, 0, 1, LV_GRID_ALIGN_STRETCH, 4, 1);
    lv_slider_set_range(slider, 0, chart_coords.x2 - chart_coords.x1 - lv_obj_get_style_pad_left(chart_data.chart, LV_PART_MAIN));

    // Create the vertical line to show position
    lv_obj_t* obj_line = lv_obj_create(lv_screen_active());
    lv_obj_remove_style_all(obj_line);
    lv_obj_set_size(obj_line, 1, 200);
    lv_obj_set_style_bg_color(obj_line, lv_color_make(162, 214, 156), LV_PART_MAIN);
    lv_obj_set_style_bg_opa(obj_line, LV_OPA_80, LV_PART_MAIN);

    chart_data.obj_line_x = chart_coords.x1 + lv_obj_get_style_pad_left(chart_data.chart, LV_PART_MAIN);
    lv_obj_set_pos(obj_line, chart_data.obj_line_x, chart_coords.y1);
    lv_obj_add_event_cb(slider, slider_event_cb, LV_EVENT_VALUE_CHANGED, obj_line);
}