/**
 * @file lv_btnm.c
 *
 */

/*********************
 *      INCLUDES
 *********************/
#include "lv_btnmatrix.h"
#if LV_USE_BTNMATRIX != 0

#include "../lv_misc/lv_debug.h"
#include "../lv_core/lv_group.h"
#include "../lv_draw/lv_draw.h"
#include "../lv_core/lv_refr.h"
#include "../lv_themes/lv_theme.h"
#include "../lv_misc/lv_txt.h"

/*********************
 *      DEFINES
 *********************/
#define LV_OBJX_NAME "lv_btnmatrix"

/**********************
 *      TYPEDEFS
 **********************/

/**********************
 *  STATIC PROTOTYPES
 **********************/
static lv_res_t lv_btnmatrix_signal(lv_obj_t * btnm, lv_signal_t sign, void * param);
static lv_design_res_t lv_btnmatrix_design(lv_obj_t * btnm, const lv_area_t * clip_area, lv_design_mode_t mode);
static lv_style_list_t * lv_btnmatrix_get_style(lv_obj_t * btnm, uint8_t part);

static uint8_t get_button_width(lv_btnmatrix_ctrl_t ctrl_bits);
static bool button_is_hidden(lv_btnmatrix_ctrl_t ctrl_bits);
static bool button_is_repeat_disabled(lv_btnmatrix_ctrl_t ctrl_bits);
static bool button_is_inactive(lv_btnmatrix_ctrl_t ctrl_bits);
static bool button_is_click_trig(lv_btnmatrix_ctrl_t ctrl_bits);
static bool button_is_tgl_enabled(lv_btnmatrix_ctrl_t ctrl_bits);
static bool button_get_tgl_state(lv_btnmatrix_ctrl_t ctrl_bits);
static uint16_t get_button_from_point(lv_obj_t * btnm, lv_point_t * p);
static void allocate_btn_areas_and_controls(const lv_obj_t * btnm, const char ** map);
static void invalidate_button_area(const lv_obj_t * btnm, uint16_t btn_idx);
static bool maps_are_identical(const char ** map1, const char ** map2);
static void make_one_button_toggled(lv_obj_t * btnm, uint16_t btn_idx);

/**********************
 *  STATIC VARIABLES
 **********************/
static const char * lv_btnmatrix_def_map[] = {"Btn1", "Btn2", "Btn3", "\n", "Btn4", "Btn5", ""};

static lv_design_cb_t ancestor_design_f;
static lv_signal_cb_t ancestor_signal;

/**********************
 *      MACROS
 **********************/

/**********************
 *   GLOBAL FUNCTIONS
 **********************/

/**
 * Create a button matrix objects
 * @param par pointer to an object, it will be the parent of the new button matrix
 * @param copy pointer to a button matrix object, if not NULL then the new object will be copied
 * from it
 * @return pointer to the created button matrix
 */
lv_obj_t * lv_btnmatrix_create(lv_obj_t * par, const lv_obj_t * copy)
{
    LV_LOG_TRACE("button matrix create started");

    /*Create the ancestor object*/
    lv_obj_t * btnm = lv_obj_create(par, copy);
    LV_ASSERT_MEM(btnm);
    if(btnm == NULL) return NULL;

    if(ancestor_signal == NULL) ancestor_signal = lv_obj_get_signal_cb(btnm);

    /*Allocate the object type specific extended data*/
    lv_btnmatrix_ext_t * ext = lv_obj_allocate_ext_attr(btnm, sizeof(lv_btnmatrix_ext_t));
    LV_ASSERT_MEM(ext);
    if(ext == NULL) {
        lv_obj_del(btnm);
        return NULL;
    }

    ext->btn_cnt        = 0;
    ext->btn_id_pr      = LV_BTNMATRIX_BTN_NONE;
    ext->btn_id_focused = LV_BTNMATRIX_BTN_NONE;
    ext->btn_id_act     = LV_BTNMATRIX_BTN_NONE;
    ext->button_areas   = NULL;
    ext->ctrl_bits      = NULL;
    ext->map_p          = NULL;
    ext->recolor        = 0;
    ext->one_check      = 0;
    lv_style_list_init(&ext->style_btn);
    ext->style_btn.ignore_trans = 1;

    if(ancestor_design_f == NULL) ancestor_design_f = lv_obj_get_design_cb(btnm);

    lv_obj_set_signal_cb(btnm, lv_btnmatrix_signal);
    lv_obj_set_design_cb(btnm, lv_btnmatrix_design);

    /*Init the new button matrix object*/
    if(copy == NULL) {
        lv_btnmatrix_set_map(btnm, lv_btnmatrix_def_map);
        lv_obj_set_size(btnm, LV_DPI * 2, LV_DPI * 1);
        lv_theme_apply(btnm, LV_THEME_BTNMATRIX);
    }
    /*Copy an existing object*/
    else {
        lv_btnmatrix_ext_t * copy_ext = lv_obj_get_ext_attr(copy);
        lv_btnmatrix_set_map(btnm, copy_ext->map_p);
        lv_btnmatrix_set_ctrl_map(btnm, copy_ext->ctrl_bits);
        lv_style_list_copy(&ext->style_btn, &copy_ext->style_btn);
    }

    LV_LOG_INFO("button matrix created");

    return btnm;
}

/*=====================
 * Setter functions
 *====================*/

/**
 * Set a new map. Buttons will be created/deleted according to the map. The
 * button matrix keeps a reference to the map and so the string array must not
 * be deallocated during the life of the matrix.
 * @param btnm pointer to a button matrix object
 * @param map pointer a string array. The last string has to be: "". Use "\n" to make a line break.
 */
void lv_btnmatrix_set_map(lv_obj_t * btnm, const char * map[])
{
    LV_ASSERT_OBJ(btnm, LV_OBJX_NAME);
    LV_ASSERT_NULL(map);

    /*
     * lv_btnmatrix_set_map is called on receipt of signals such as
     * LV_SIGNAL_CORD_CHG regardless of whether the map has changed (e.g.
     * calling lv_obj_align on the map will trigger this).
     *
     * We check if the map has changed here to avoid overwriting changes made
     * to hidden/longpress/disabled states after the map was originally set.
     *
     * TODO: separate all map set/allocation from layout code below and skip
     * set/allocation when map hasn't changed.
     */
    lv_btnmatrix_ext_t * ext = lv_obj_get_ext_attr(btnm);
    if(!maps_are_identical(ext->map_p, map)) {

        /*Analyze the map and create the required number of buttons*/
        allocate_btn_areas_and_controls(btnm, map);
    }
    ext->map_p = map;

    /*Set size and positions of the buttons*/
    lv_style_int_t left = lv_obj_get_style_pad_left(btnm, LV_BTNMATRIX_PART_BG);
    lv_style_int_t right = lv_obj_get_style_pad_right(btnm, LV_BTNMATRIX_PART_BG);
    lv_style_int_t top = lv_obj_get_style_pad_top(btnm, LV_BTNMATRIX_PART_BG);
    lv_style_int_t bottom = lv_obj_get_style_pad_bottom(btnm, LV_BTNMATRIX_PART_BG);
    lv_style_int_t inner = lv_obj_get_style_pad_inner(btnm, LV_BTNMATRIX_PART_BG);

    lv_coord_t max_w            = lv_obj_get_width(btnm) - left - right;
    lv_coord_t max_h            = lv_obj_get_height(btnm) - top - bottom;
    lv_coord_t act_y            = top;

    /*Count the lines to calculate button height*/
    uint8_t line_cnt = 1;
    uint8_t li;
    for(li = 0; strlen(map[li]) != 0; li++) {
        if(strcmp(map[li], "\n") == 0) line_cnt++;
    }

    lv_coord_t btn_h = max_h - ((line_cnt - 1) * inner);
    btn_h            = btn_h / line_cnt;
    btn_h--; /*-1 because e.g. height = 100 means 101 pixels (0..100)*/

    /* Count the units and the buttons in a line
     * (A button can be 1,2,3... unit wide)*/
    uint16_t unit_act_cnt;       /*Number of units currently put in a row*/
    uint16_t i_tot          = 0; /*Act. index in the str map*/
    uint16_t btn_i          = 0; /*Act. index of button areas*/
    const char ** map_p_tmp = map;

    /*Count the units and the buttons in a line*/
    while(1) {
        uint16_t unit_cnt = 0;           /*Number of units in a row*/
        uint16_t btn_cnt = 0;            /*Number of buttons in a row*/
        /*Count the buttons in a line*/
        while(strcmp(map_p_tmp[btn_cnt], "\n") != 0 && strlen(map_p_tmp[btn_cnt]) != 0) { /*Check a line*/
            unit_cnt += get_button_width(ext->ctrl_bits[btn_i + btn_cnt]);
            btn_cnt++;
        }

        /*Make sure the last row is at the bottom of 'btnm'*/
        if(map_p_tmp[btn_cnt][0] == '\0') { /*Last row?*/
            btn_h = lv_obj_get_height(btnm) - act_y - bottom - 1;
        }

        lv_bidi_dir_t base_dir = lv_obj_get_base_dir(btnm);

        /*Only deal with the non empty lines*/
        if(btn_cnt != 0) {
            /*Calculate the width of all units*/
            lv_coord_t all_unit_w = max_w - ((btn_cnt - 1) * inner);

            /*Set the button size and positions and set the texts*/
            uint16_t i;
            lv_coord_t act_x;

            unit_act_cnt = 0;
            for(i = 0; i < btn_cnt; i++) {
                /* one_unit_w = all_unit_w / unit_cnt
                 * act_unit_w = one_unit_w * button_width
                 * do this two operations but the multiply first to divide a greater number */
                lv_coord_t act_unit_w = (all_unit_w * get_button_width(ext->ctrl_bits[btn_i])) / unit_cnt;
                act_unit_w--; /*-1 because e.g. width = 100 means 101 pixels (0..100)*/

                /*Always recalculate act_x because of rounding errors */
                if(base_dir == LV_BIDI_DIR_RTL)  {
                    act_x = (unit_act_cnt * all_unit_w) / unit_cnt + i * inner;
                    act_x = lv_obj_get_width(btnm) - right - act_x - act_unit_w - 1;
                }
                else {
                    act_x = (unit_act_cnt * all_unit_w) / unit_cnt + i * inner +
                            left;
                }
                /* Set the button's area.
                 * If inner padding is zero then use the prev. button x2 as x1 to avoid rounding
                 * errors*/
                if(btn_i != 0 && inner == 0 && ((act_x != left && base_dir != LV_BIDI_DIR_RTL) ||
                                                (act_x + act_unit_w == max_w - right && base_dir == LV_BIDI_DIR_RTL))) {
                    lv_area_set(&ext->button_areas[btn_i], ext->button_areas[btn_i - 1].x2, act_y, act_x + act_unit_w,
                                act_y + btn_h);
                }
                else {
                    lv_area_set(&ext->button_areas[btn_i], act_x, act_y, act_x + act_unit_w, act_y + btn_h);
                }

                unit_act_cnt += get_button_width(ext->ctrl_bits[btn_i]);

                i_tot++;
                btn_i++;
            }
        }
        act_y += btn_h + inner + 1;

        if(strlen(map_p_tmp[btn_cnt]) == 0) break; /*Break on end of map*/
        map_p_tmp = &map_p_tmp[btn_cnt + 1];       /*Set the map to the next line*/
        i_tot++;                                   /*Skip the '\n'*/
    }

    lv_obj_invalidate(btnm);
}

/**
 * Set the button control map (hidden, disabled etc.) for a button matrix. The
 * control map array will be copied and so may be deallocated after this
 * function returns.
 * @param btnm pointer to a button matrix object
 * @param ctrl_map pointer to an array of `lv_btn_ctrl_t` control bytes. The
 *                 length of the array and position of the elements must match
 *                 the number and order of the individual buttons (i.e. excludes
 *                 newline entries).
 *                 An element of the map should look like e.g.:
 *                 `ctrl_map[0] = width | LV_BTNMATRIX_CTRL_NO_REPEAT |  LV_BTNMATRIX_CTRL_TGL_ENABLE`
 */
void lv_btnmatrix_set_ctrl_map(lv_obj_t * btnm, const lv_btnmatrix_ctrl_t ctrl_map[])
{
    LV_ASSERT_OBJ(btnm, LV_OBJX_NAME);

    lv_btnmatrix_ext_t * ext = lv_obj_get_ext_attr(btnm);
    _lv_memcpy(ext->ctrl_bits, ctrl_map, sizeof(lv_btnmatrix_ctrl_t) * ext->btn_cnt);

    lv_btnmatrix_set_map(btnm, ext->map_p);
}

/**
 * Set the focused button i.e. visually highlight it.
 * @param btnm pointer to button matrix object
 * @param id index of the button to focus(`LV_BTNMATRIX_BTN_NONE` to remove focus)
 */
void lv_btnmatrix_set_focused_btn(lv_obj_t * btnm, uint16_t id)
{
    LV_ASSERT_OBJ(btnm, LV_OBJX_NAME);

    lv_btnmatrix_ext_t * ext = lv_obj_get_ext_attr(btnm);

    if(id >= ext->btn_cnt && id != LV_BTNMATRIX_BTN_NONE) return;

    if(id == ext->btn_id_focused) return;

    ext->btn_id_focused = id;
    lv_obj_invalidate(btnm);
}


/**
 * Enable recoloring of button's texts
 * @param btnm pointer to button matrix object
 * @param en true: enable recoloring; false: disable
 */
void lv_btnmatrix_set_recolor(const lv_obj_t * btnm, bool en)
{
    LV_ASSERT_OBJ(btnm, LV_OBJX_NAME);

    lv_btnmatrix_ext_t * ext = lv_obj_get_ext_attr(btnm);

    ext->recolor = en;
    lv_obj_invalidate(btnm);
}

/**
 * Set the attributes of a button of the button matrix
 * @param btnm pointer to button matrix object
 * @param btn_id 0 based index of the button to modify. (Not counting new lines)
 */
void lv_btnmatrix_set_btn_ctrl(const lv_obj_t * btnm, uint16_t btn_id, lv_btnmatrix_ctrl_t ctrl)
{
    LV_ASSERT_OBJ(btnm, LV_OBJX_NAME);

    lv_btnmatrix_ext_t * ext = lv_obj_get_ext_attr(btnm);

    if(btn_id >= ext->btn_cnt) return;

    ext->ctrl_bits[btn_id] |= ctrl;
    invalidate_button_area(btnm, btn_id);
}

/**
 * Clear the attributes of a button of the button matrix
 * @param btnm pointer to button matrix object
 * @param btn_id 0 based index of the button to modify. (Not counting new lines)
 */
void lv_btnmatrix_clear_btn_ctrl(const lv_obj_t * btnm, uint16_t btn_id, lv_btnmatrix_ctrl_t ctrl)
{
    LV_ASSERT_OBJ(btnm, LV_OBJX_NAME);

    lv_btnmatrix_ext_t * ext = lv_obj_get_ext_attr(btnm);

    if(btn_id >= ext->btn_cnt) return;

    ext->ctrl_bits[btn_id] &= (~ctrl);
    invalidate_button_area(btnm, btn_id);
}

/**
 * Set the attributes of all buttons of a button matrix
 * @param btnm pointer to a button matrix object
 * @param ctrl attribute(s) to set from `lv_btnmatrix_ctrl_t`. Values can be ORed.
 */
void lv_btnmatrix_set_btn_ctrl_all(lv_obj_t * btnm, lv_btnmatrix_ctrl_t ctrl)
{
    LV_ASSERT_OBJ(btnm, LV_OBJX_NAME);

    lv_btnmatrix_ext_t * ext = lv_obj_get_ext_attr(btnm);
    uint16_t i;
    for(i = 0; i < ext->btn_cnt; i++) {
        lv_btnmatrix_set_btn_ctrl(btnm, i, ctrl);
    }
}

/**
 * Clear the attributes of all buttons of a button matrix
 * @param btnm pointer to a button matrix object
 * @param ctrl attribute(s) to set from `lv_btnmatrix_ctrl_t`. Values can be ORed.
 * @param en true: set the attributes; false: clear the attributes
 */
void lv_btnmatrix_clear_btn_ctrl_all(lv_obj_t * btnm, lv_btnmatrix_ctrl_t ctrl)
{
    LV_ASSERT_OBJ(btnm, LV_OBJX_NAME);

    lv_btnmatrix_ext_t * ext = lv_obj_get_ext_attr(btnm);
    uint16_t i;
    for(i = 0; i < ext->btn_cnt; i++) {
        lv_btnmatrix_clear_btn_ctrl(btnm, i, ctrl);
    }
}

/**
 * Set a single buttons relative width.
 * This method will cause the matrix be regenerated and is a relatively
 * expensive operation. It is recommended that initial width be specified using
 * `lv_btnmatrix_set_ctrl_map` and this method only be used for dynamic changes.
 * @param btnm pointer to button matrix object
 * @param btn_id 0 based index of the button to modify.
 * @param width Relative width compared to the buttons in the same row. [1..7]
 */
void lv_btnmatrix_set_btn_width(lv_obj_t * btnm, uint16_t btn_id, uint8_t width)
{
    LV_ASSERT_OBJ(btnm, LV_OBJX_NAME);


    lv_btnmatrix_ext_t * ext = lv_obj_get_ext_attr(btnm);
    if(btn_id >= ext->btn_cnt) return;
    ext->ctrl_bits[btn_id] &= (~LV_BTNMATRIX_WIDTH_MASK);
    ext->ctrl_bits[btn_id] |= (LV_BTNMATRIX_WIDTH_MASK & width);

    lv_btnmatrix_set_map(btnm, ext->map_p);
}

/**
 * Make the button matrix like a selector widget (only one button may be toggled at a time).
 * `Checkable` must be enabled on the buttons you want to be selected with `lv_btnmatrix_set_ctrl` or
 * `lv_btnmatrix_set_btn_ctrl_all`.
 * @param btnm Button matrix object
 * @param one_chk Whether "one check" mode is enabled
 */
void lv_btnmatrix_set_one_check(lv_obj_t * btnm, bool one_chk)
{
    LV_ASSERT_OBJ(btnm, LV_OBJX_NAME);

    lv_btnmatrix_ext_t * ext = lv_obj_get_ext_attr(btnm);
    ext->one_check     = one_chk;

    /*If more than one button is toggled only the first one should be*/
    make_one_button_toggled(btnm, 0);
}

/**
 * Set the align of the map text (left, right or center)
 * @param btnm pointer to a btnmatrix object
 * @param align LV_LABEL_ALIGN_LEFT, LV_LABEL_ALIGN_RIGHT or LV_LABEL_ALIGN_CENTER
 */
void lv_btnmatrix_set_align(lv_obj_t* btnm, lv_label_align_t align)
{
    LV_ASSERT_OBJ(btnm, LV_OBJX_NAME);

    lv_btnmatrix_ext_t* ext = lv_obj_get_ext_attr(btnm);
    if (ext->align == align) return;

    ext->align = align;

    lv_obj_invalidate(btnm);
}

/*=====================
 * Getter functions
 *====================*/

/**
 * Get the current map of a button matrix
 * @param btnm pointer to a button matrix object
 * @return the current map
 */
const char ** lv_btnmatrix_get_map_array(const lv_obj_t * btnm)
{
    LV_ASSERT_OBJ(btnm, LV_OBJX_NAME);

    lv_btnmatrix_ext_t * ext = lv_obj_get_ext_attr(btnm);
    return ext->map_p;
}

/**
 * Check whether the button's text can use recolor or not
 * @param btnm pointer to button matrix object
 * @return true: text recolor enable; false: disabled
 */
bool lv_btnmatrix_get_recolor(const lv_obj_t * btnm)
{
    LV_ASSERT_OBJ(btnm, LV_OBJX_NAME);

    lv_btnmatrix_ext_t * ext = lv_obj_get_ext_attr(btnm);

    return ext->recolor;
}

/**
 * Get the index of the lastly "activated" button by the user (pressed, released etc)
 * Useful in the the `event_cb` to get the text of the button, check if hidden etc.
 * @param btnm pointer to button matrix object
 * @return  index of the last released button (LV_BTNMATRIX_BTN_NONE: if unset)
 */
uint16_t lv_btnmatrix_get_active_btn(const lv_obj_t * btnm)
{
    LV_ASSERT_OBJ(btnm, LV_OBJX_NAME);

    lv_btnmatrix_ext_t * ext = lv_obj_get_ext_attr(btnm);
    return ext->btn_id_act;
}

/**
 * Get the text of the lastly "activated" button by the user (pressed, released etc)
 * Useful in the the `event_cb`
 * @param btnm pointer to button matrix object
 * @return text of the last released button (NULL: if unset)
 */
const char * lv_btnmatrix_get_active_btn_text(const lv_obj_t * btnm)
{
    LV_ASSERT_OBJ(btnm, LV_OBJX_NAME);

    lv_btnmatrix_ext_t * ext = lv_obj_get_ext_attr(btnm);
    if(ext->btn_id_act != LV_BTNMATRIX_BTN_NONE) {
        return lv_btnmatrix_get_btn_text(btnm, ext->btn_id_act);
    }
    else {
        return NULL;
    }
}

/**
 * Get the pressed button's index.
 * The button be really pressed by the user or manually set to pressed with `lv_btnmatrix_set_pressed`
 * @param btnm pointer to button matrix object
 * @return  index of the pressed button (LV_BTNMATRIX_BTN_NONE: if unset)
 */
uint16_t lv_btnmatrix_get_focused_btn(const lv_obj_t * btnm)
{
    LV_ASSERT_OBJ(btnm, LV_OBJX_NAME);

    lv_btnmatrix_ext_t * ext = lv_obj_get_ext_attr(btnm);
    return ext->btn_id_focused;
}

/**
 * Get the button's text
 * @param btnm pointer to button matrix object
 * @param btn_id the index a button not counting new line characters. (The return value of
 * lv_btnmatrix_get_pressed/released)
 * @return  text of btn_index` button
 */
const char * lv_btnmatrix_get_btn_text(const lv_obj_t * btnm, uint16_t btn_id)
{
    LV_ASSERT_OBJ(btnm, LV_OBJX_NAME);

    lv_btnmatrix_ext_t * ext = lv_obj_get_ext_attr(btnm);
    if(btn_id > ext->btn_cnt) return NULL;

    uint16_t txt_i = 0;
    uint16_t btn_i = 0;

    /* Search the text of ext->btn_pr the buttons text in the map
     * Skip "\n"-s*/
    while(btn_i != btn_id) {
        btn_i++;
        txt_i++;
        if(strcmp(ext->map_p[txt_i], "\n") == 0) txt_i++;
    }

    if(btn_i == ext->btn_cnt) return NULL;

    return ext->map_p[txt_i];
}

/**
 * Get the whether a control value is enabled or disabled for button of a button matrix
 * @param btnm pointer to a button matrix object
 * @param btn_id the index a button not counting new line characters. (E.g. the return value of
 * lv_btnmatrix_get_pressed/released)
 * @param ctrl control values to check (ORed value can be used)
 * @return true: long press repeat is disabled; false: long press repeat enabled
 */
bool lv_btnmatrix_get_btn_ctrl(lv_obj_t * btnm, uint16_t btn_id, lv_btnmatrix_ctrl_t ctrl)
{
    LV_ASSERT_OBJ(btnm, LV_OBJX_NAME);

    lv_btnmatrix_ext_t * ext = lv_obj_get_ext_attr(btnm);
    if(btn_id >= ext->btn_cnt) return false;

    return (ext->ctrl_bits[btn_id] & ctrl) ? true : false;
}


/**
 * Find whether "one check" mode is enabled.
 * @param btnm Button matrix object
 * @return whether "one check" mode is enabled
 */
bool lv_btnmatrix_get_one_check(const lv_obj_t * btnm)
{
    LV_ASSERT_OBJ(btnm, LV_OBJX_NAME);

    lv_btnmatrix_ext_t * ext = lv_obj_get_ext_attr(btnm);

    return ext->one_check;
}

/**
 * Get the align attribute
 * @param btnm pointer to a btnmatrix object
 * @return LV_LABEL_ALIGN_LEFT, LV_LABEL_ALIGN_RIGHT or LV_LABEL_ALIGN_CENTER
 */
lv_label_align_t lv_btnmatrix_get_align(const lv_obj_t* btnm)
{
    LV_ASSERT_OBJ(btnm, LV_OBJX_NAME);

    lv_btnmatrix_ext_t* ext = lv_obj_get_ext_attr(btnm);

    lv_label_align_t align = ext->align;

    if (align == LV_LABEL_ALIGN_AUTO) {
#if LV_USE_BIDI
        lv_bidi_dir_t base_dir = lv_obj_get_base_dir(btnm);
        if (base_dir == LV_BIDI_DIR_RTL) align = LV_LABEL_ALIGN_RIGHT;
        else align = LV_LABEL_ALIGN_LEFT;
#else
        align = LV_LABEL_ALIGN_LEFT;
#endif
    }

    return align;
}

/**********************
 *   STATIC FUNCTIONS
 **********************/

/**
 * Handle the drawing related tasks of the button matrix
 * @param btnm pointer to a button matrix object
 * @param clip_area the object will be drawn only in this area
 * @param mode LV_DESIGN_COVER_CHK: only check if the object fully covers the 'mask_p' area
 *                                  (return 'true' if yes)
 *             LV_DESIGN_DRAW: draw the object (always return 'true')
 *             LV_DESIGN_DRAW_POST: drawing after every children are drawn
 * @param return an element of `lv_design_res_t`
 */
static lv_design_res_t lv_btnmatrix_design(lv_obj_t * btnm, const lv_area_t * clip_area, lv_design_mode_t mode)
{
    if(mode == LV_DESIGN_COVER_CHK) {
        return ancestor_design_f(btnm, clip_area, mode);
    }
    /*Draw the object*/
    else if(mode == LV_DESIGN_DRAW_MAIN) {
        ancestor_design_f(btnm, clip_area, mode);

        lv_btnmatrix_ext_t * ext         = lv_obj_get_ext_attr(btnm);
        if(ext->btn_cnt == 0) return LV_DESIGN_RES_OK;
        lv_area_t area_btnm;
        lv_obj_get_coords(btnm, &area_btnm);

        lv_area_t area_tmp;
        lv_coord_t btn_w;
        lv_coord_t btn_h;

        uint16_t btn_i = 0;
        uint16_t txt_i = 0;
        lv_txt_flag_t txt_flag = LV_TXT_FLAG_NONE;
        if (ext->recolor) txt_flag |= LV_TXT_FLAG_RECOLOR;
        lv_label_align_t align = lv_btnmatrix_get_align(btnm);
        if (align == LV_LABEL_ALIGN_CENTER) txt_flag |= LV_TXT_FLAG_CENTER;
        if (align == LV_LABEL_ALIGN_RIGHT) txt_flag |= LV_TXT_FLAG_RIGHT;

        lv_draw_rect_dsc_t draw_rect_rel_dsc;
        lv_draw_label_dsc_t draw_label_rel_dsc;

        lv_draw_rect_dsc_t draw_rect_chk_dsc;
        lv_draw_label_dsc_t draw_label_chk_dsc;

        lv_draw_rect_dsc_t draw_rect_ina_dsc;
        lv_draw_label_dsc_t draw_label_ina_dsc;

        lv_draw_rect_dsc_t draw_rect_tmp_dsc;
        lv_draw_label_dsc_t draw_label_tmp_dsc;

        /*The state changes without re-caching the styles, disable the use of cache*/
        lv_state_t state_ori = btnm->state;
        btnm->state = LV_STATE_DEFAULT;
        lv_draw_rect_dsc_init(&draw_rect_rel_dsc);
        lv_draw_label_dsc_init(&draw_label_rel_dsc);
        lv_obj_init_draw_rect_dsc(btnm, LV_BTNMATRIX_PART_BTN, &draw_rect_rel_dsc);
        lv_obj_init_draw_label_dsc(btnm, LV_BTNMATRIX_PART_BTN, &draw_label_rel_dsc);
        draw_label_rel_dsc.flag = txt_flag;
        btnm->state = state_ori;

        bool chk_inited = false;
        bool disabled_inited = false;

        lv_style_int_t padding_top = lv_obj_get_style_pad_top(btnm, LV_BTNMATRIX_PART_BG);
        lv_style_int_t padding_bottom = lv_obj_get_style_pad_bottom(btnm, LV_BTNMATRIX_PART_BG);

        for(btn_i = 0; btn_i < ext->btn_cnt; btn_i++, txt_i++) {
            /*Search the next valid text in the map*/
            while(strcmp(ext->map_p[txt_i], "\n") == 0) {
                txt_i++;
            }

            /*Skip hidden buttons*/
            if(button_is_hidden(ext->ctrl_bits[btn_i])) continue;

            lv_area_copy(&area_tmp, &ext->button_areas[btn_i]);
            area_tmp.x1 += area_btnm.x1;
            area_tmp.y1 += area_btnm.y1;
            area_tmp.x2 += area_btnm.x1;
            area_tmp.y2 += area_btnm.y1;

            btn_w = lv_area_get_width(&area_tmp);
            btn_h = lv_area_get_height(&area_tmp);

            /*Choose the style*/
            lv_draw_rect_dsc_t * draw_rect_dsc_act;
            lv_draw_label_dsc_t * draw_label_dsc_act;
            bool tgl_state = button_get_tgl_state(ext->ctrl_bits[btn_i]);

            if(tgl_state) {
                if(!chk_inited) {
                    btnm->state = LV_STATE_CHECKED;
                    lv_draw_rect_dsc_init(&draw_rect_chk_dsc);
                    lv_draw_label_dsc_init(&draw_label_chk_dsc);
                    lv_obj_init_draw_rect_dsc(btnm, LV_BTNMATRIX_PART_BTN, &draw_rect_chk_dsc);
                    lv_obj_init_draw_label_dsc(btnm, LV_BTNMATRIX_PART_BTN, &draw_label_chk_dsc);
                    draw_label_chk_dsc.flag = txt_flag;
                    btnm->state = state_ori;
                    chk_inited = true;
                }
            }

            if(button_is_inactive(ext->ctrl_bits[btn_i])) {
                if(!disabled_inited) {
                    btnm->state = LV_STATE_DISABLED;
                    lv_draw_rect_dsc_init(&draw_rect_ina_dsc);
                    lv_draw_label_dsc_init(&draw_label_ina_dsc);
                    lv_obj_init_draw_rect_dsc(btnm, LV_BTNMATRIX_PART_BTN, &draw_rect_ina_dsc);
                    lv_obj_init_draw_label_dsc(btnm, LV_BTNMATRIX_PART_BTN, &draw_label_ina_dsc);
                    draw_label_ina_dsc.flag = txt_flag;
                    btnm->state = state_ori;
                    disabled_inited = true;
                }
                draw_rect_dsc_act = &draw_rect_ina_dsc;
                draw_label_dsc_act = &draw_label_ina_dsc;
            }
            /*Simple released or checked buttons button*/
            else if(btn_i != ext->btn_id_pr && btn_i != ext->btn_id_focused) {
                draw_rect_dsc_act = tgl_state ? &draw_rect_chk_dsc : &draw_rect_rel_dsc;
                draw_label_dsc_act = tgl_state ? &draw_label_chk_dsc : &draw_label_rel_dsc;
            }
            /*Focused and/or pressed + checked or released button*/
            else {
                btnm->state = LV_STATE_DEFAULT;
                if(tgl_state) btnm->state = LV_STATE_CHECKED;
                if(ext->btn_id_pr == btn_i) btnm->state |= LV_STATE_PRESSED;
                if(ext->btn_id_focused == btn_i) {
                    btnm->state |= LV_STATE_FOCUSED;
                    if(state_ori & LV_STATE_EDITED) btnm->state |= LV_STATE_EDITED;
                }

                lv_draw_rect_dsc_init(&draw_rect_tmp_dsc);
                lv_draw_label_dsc_init(&draw_label_tmp_dsc);
                lv_obj_init_draw_rect_dsc(btnm, LV_BTNMATRIX_PART_BTN, &draw_rect_tmp_dsc);
                lv_obj_init_draw_label_dsc(btnm, LV_BTNMATRIX_PART_BTN, &draw_label_tmp_dsc);
                draw_label_tmp_dsc.flag = txt_flag;
                draw_rect_dsc_act = &draw_rect_tmp_dsc;
                draw_label_dsc_act = &draw_label_tmp_dsc;

                btnm->state = state_ori;
            }

            lv_style_int_t border_part_ori = draw_rect_dsc_act->border_side;

            /*Remove borders on the edges if `LV_BORDER_INTERNAL`*/
            if(border_part_ori & LV_BORDER_SIDE_INTERNAL) {
                /*Top/Bottom lines*/
                if(area_tmp.y1 == btnm->coords.y1 + padding_top) {
                    draw_rect_dsc_act->border_side &= ~LV_BORDER_SIDE_TOP;
                }
                if(area_tmp.y2 == btnm->coords.y2 - padding_bottom) {
                    draw_rect_dsc_act->border_side &= ~LV_BORDER_SIDE_BOTTOM;
                }

                /*Left/right columns*/
                if(txt_i == 0) { /*First button*/
                    draw_rect_dsc_act->border_side &= ~LV_BORDER_SIDE_LEFT;
                }
                else if(strcmp(ext->map_p[txt_i - 1], "\n") == 0) {
                    draw_rect_dsc_act->border_side &= ~LV_BORDER_SIDE_LEFT;
                }

                if(ext->map_p[txt_i + 1][0] == '\0' || strcmp(ext->map_p[txt_i + 1], "\n") == 0) {
                    draw_rect_dsc_act->border_side &= ~LV_BORDER_SIDE_RIGHT;
                }
            }

            lv_draw_rect(&area_tmp, clip_area, draw_rect_dsc_act);

            draw_rect_dsc_act->border_side = border_part_ori;

            /*Calculate the size of the text*/
            const lv_font_t * font = draw_label_dsc_act->font;
            lv_style_int_t letter_space = draw_label_dsc_act->letter_space;
            lv_style_int_t line_space = draw_label_dsc_act->line_space;
            const char * txt = ext->map_p[txt_i];
            lv_point_t txt_size;
            _lv_txt_get_size(&txt_size, txt, font, letter_space,
                             line_space, lv_area_get_width(&area_btnm), txt_flag);

            area_tmp.x1 += (btn_w - txt_size.x) / 2;
            area_tmp.y1 += (btn_h - txt_size.y) / 2;
            area_tmp.x2 = area_tmp.x1 + txt_size.x;
            area_tmp.y2 = area_tmp.y1 + txt_size.y;

            lv_draw_label(&area_tmp, clip_area, draw_label_dsc_act, txt, NULL);
        }
    }
    else if(mode == LV_DESIGN_DRAW_POST) {
        ancestor_design_f(btnm, clip_area, mode);
    }
    return LV_DESIGN_RES_OK;
}

/**
 * Signal function of the button matrix
 * @param btnm pointer to a button matrix object
 * @param sign a signal type from lv_signal_t enum
 * @param param pointer to a signal specific variable
 * @return LV_RES_OK: the object is not deleted in the function; LV_RES_INV: the object is deleted
 */
static lv_res_t lv_btnmatrix_signal(lv_obj_t * btnm, lv_signal_t sign, void * param)
{
    lv_res_t res;
    if(sign == LV_SIGNAL_GET_STYLE) {
        lv_get_style_info_t * info = param;
        info->result = lv_btnmatrix_get_style(btnm, info->part);
        if(info->result != NULL) return LV_RES_OK;
        else return ancestor_signal(btnm, sign, param);
    }

    /* Include the ancient signal function */
    res = ancestor_signal(btnm, sign, param);
    if(res != LV_RES_OK) return res;
    if(sign == LV_SIGNAL_GET_TYPE) return lv_obj_handle_get_type_signal(param, LV_OBJX_NAME);

    lv_btnmatrix_ext_t * ext = lv_obj_get_ext_attr(btnm);
    lv_point_t p;
    if(sign == LV_SIGNAL_CLEANUP) {
        lv_obj_clean_style_list(btnm, LV_BTNMATRIX_PART_BTN);
        lv_mem_free(ext->button_areas);
        lv_mem_free(ext->ctrl_bits);
    }
    else if(sign == LV_SIGNAL_STYLE_CHG) {
        lv_btnmatrix_set_map(btnm, ext->map_p);
    }
    else if(sign == LV_SIGNAL_COORD_CHG) {
        if(lv_obj_get_width(btnm) != lv_area_get_width(param) || lv_obj_get_height(btnm) != lv_area_get_height(param)) {
            lv_btnmatrix_set_map(btnm, ext->map_p);
        }
    }
    else if(sign == LV_SIGNAL_PRESSED) {
        invalidate_button_area(btnm, ext->btn_id_pr);

        lv_indev_type_t indev_type = lv_indev_get_type(lv_indev_get_act());
        if(indev_type == LV_INDEV_TYPE_POINTER || indev_type == LV_INDEV_TYPE_BUTTON) {
            uint16_t btn_pr;
            /*Search the pressed area*/
            lv_indev_get_point(param, &p);
            btn_pr = get_button_from_point(btnm, &p);
            /*Handle the case where there is no button there*/
            if(btn_pr != LV_BTNMATRIX_BTN_NONE) {
                if(button_is_inactive(ext->ctrl_bits[btn_pr]) == false &&
                   button_is_hidden(ext->ctrl_bits[btn_pr]) == false) {
                    invalidate_button_area(btnm, ext->btn_id_pr) /*Invalidate the old area*/;
                    ext->btn_id_pr = btn_pr;
                    ext->btn_id_act = btn_pr;
                    invalidate_button_area(btnm, ext->btn_id_pr); /*Invalidate the new area*/
                }
            }
        }
#if LV_USE_GROUP
        else if(indev_type == LV_INDEV_TYPE_KEYPAD || (indev_type == LV_INDEV_TYPE_ENCODER &&
                                                       lv_group_get_editing(lv_obj_get_group(btnm)))) {
            ext->btn_id_pr = ext->btn_id_focused;
            invalidate_button_area(btnm, ext->btn_id_focused);
        }
#endif

        if(ext->btn_id_pr != LV_BTNMATRIX_BTN_NONE) {
            if(button_is_click_trig(ext->ctrl_bits[ext->btn_id_pr]) == false &&
               button_is_inactive(ext->ctrl_bits[ext->btn_id_pr]) == false &&
               button_is_hidden(ext->ctrl_bits[ext->btn_id_pr]) == false) {
                uint32_t b = ext->btn_id_pr;
                res        = lv_event_send(btnm, LV_EVENT_VALUE_CHANGED, &b);
            }
        }
    }
    else if(sign == LV_SIGNAL_PRESSING) {
        uint16_t btn_pr = LV_BTNMATRIX_BTN_NONE;
        /*Search the pressed area*/
        lv_indev_t * indev = lv_indev_get_act();
        lv_indev_type_t indev_type = lv_indev_get_type(indev);
        if(indev_type == LV_INDEV_TYPE_ENCODER || indev_type == LV_INDEV_TYPE_KEYPAD) return LV_RES_OK;

        lv_indev_get_point(indev, &p);
        btn_pr = get_button_from_point(btnm, &p);
        /*Invalidate to old and the new areas*/
        if(btn_pr != ext->btn_id_pr) {
            if(ext->btn_id_pr != LV_BTNMATRIX_BTN_NONE) {
                invalidate_button_area(btnm, ext->btn_id_pr);
            }

            ext->btn_id_pr  = btn_pr;
            ext->btn_id_act = btn_pr;

            lv_indev_reset_long_press(param); /*Start the log press time again on the new button*/
            if(btn_pr != LV_BTNMATRIX_BTN_NONE &&
               button_is_inactive(ext->ctrl_bits[btn_pr]) == false &&
               button_is_hidden(ext->ctrl_bits[btn_pr]) == false) {
                /* Send VALUE_CHANGED for the newly pressed button */
                uint32_t b = btn_pr;
                res        = lv_event_send(btnm, LV_EVENT_VALUE_CHANGED, &b);
                if(res == LV_RES_OK) {
                    invalidate_button_area(btnm, btn_pr);
                }
            }
        }
    }
    else if(sign == LV_SIGNAL_RELEASED) {
        if(ext->btn_id_pr != LV_BTNMATRIX_BTN_NONE) {
            /*Toggle the button if enabled*/
            if(button_is_tgl_enabled(ext->ctrl_bits[ext->btn_id_pr]) &&
               !button_is_inactive(ext->ctrl_bits[ext->btn_id_pr])) {
                if(button_get_tgl_state(ext->ctrl_bits[ext->btn_id_pr])) {
                    ext->ctrl_bits[ext->btn_id_pr] &= (~LV_BTNMATRIX_CTRL_CHECK_STATE);
                }
                else {
                    ext->ctrl_bits[ext->btn_id_pr] |= LV_BTNMATRIX_CTRL_CHECK_STATE;
                }
                if(ext->one_check) make_one_button_toggled(btnm, ext->btn_id_pr);
            }

            /*Invalidate to old pressed area*/;
            invalidate_button_area(btnm, ext->btn_id_pr);
            invalidate_button_area(btnm, ext->btn_id_focused);


            lv_indev_type_t indev_type = lv_indev_get_type(lv_indev_get_act());
            if(indev_type == LV_INDEV_TYPE_KEYPAD || indev_type == LV_INDEV_TYPE_ENCODER) {
                ext->btn_id_focused = ext->btn_id_pr;
            }

            ext->btn_id_pr = LV_BTNMATRIX_BTN_NONE;

            if(button_is_click_trig(ext->ctrl_bits[ext->btn_id_act]) == true &&
               button_is_inactive(ext->ctrl_bits[ext->btn_id_act]) == false &&
               button_is_hidden(ext->ctrl_bits[ext->btn_id_act]) == false) {
                uint32_t b = ext->btn_id_act;
                res        = lv_event_send(btnm, LV_EVENT_VALUE_CHANGED, &b);
            }
        }
    }
    else if(sign == LV_SIGNAL_LONG_PRESS_REP) {
        if(ext->btn_id_act != LV_BTNMATRIX_BTN_NONE) {
            if(button_is_repeat_disabled(ext->ctrl_bits[ext->btn_id_act]) == false &&
               button_is_inactive(ext->ctrl_bits[ext->btn_id_act]) == false &&
               button_is_hidden(ext->ctrl_bits[ext->btn_id_act]) == false) {
                uint32_t b = ext->btn_id_act;
                res        = lv_event_send(btnm, LV_EVENT_VALUE_CHANGED, &b);
            }
        }
    }
    else if(sign == LV_SIGNAL_PRESS_LOST) {
        ext->btn_id_pr  = LV_BTNMATRIX_BTN_NONE;
        ext->btn_id_act = LV_BTNMATRIX_BTN_NONE;
        lv_obj_invalidate(btnm);
    }
    else if(sign == LV_SIGNAL_FOCUS) {
#if LV_USE_GROUP
        lv_indev_t * indev         = lv_indev_get_act();
        lv_indev_type_t indev_type = lv_indev_get_type(indev);

        /*If not focused by an input device assume the last input device*/
        if(indev == NULL) {
            indev = lv_indev_get_next(NULL);
            indev_type = lv_indev_get_type(indev);
        }

        if(indev_type == LV_INDEV_TYPE_ENCODER) {
            /*In navigation mode don't select any button but in edit mode select the fist*/
            if(lv_group_get_editing(lv_obj_get_group(btnm))) {
                ext->btn_id_focused = 0;
                ext->btn_id_act = ext->btn_id_focused;
            }
            else {
                ext->btn_id_focused = LV_BTNMATRIX_BTN_NONE;
            }
        }
        else if(indev_type == LV_INDEV_TYPE_KEYPAD) {
            ext->btn_id_focused = 0;
            ext->btn_id_act = ext->btn_id_focused;
        }

#endif
    }
    else if(sign == LV_SIGNAL_DEFOCUS || sign == LV_SIGNAL_LEAVE) {
        if(ext->btn_id_focused != LV_BTNMATRIX_BTN_NONE) invalidate_button_area(btnm, ext->btn_id_focused);
        if(ext->btn_id_pr != LV_BTNMATRIX_BTN_NONE) invalidate_button_area(btnm, ext->btn_id_pr);
        ext->btn_id_focused = LV_BTNMATRIX_BTN_NONE;
        ext->btn_id_pr = LV_BTNMATRIX_BTN_NONE;
        ext->btn_id_act = LV_BTNMATRIX_BTN_NONE;
    }
    else if(sign == LV_SIGNAL_CONTROL) {
        char c = *((char *)param);
        if(c == LV_KEY_RIGHT) {
            if(ext->btn_id_focused == LV_BTNMATRIX_BTN_NONE)
                ext->btn_id_focused = 0;
            else
                ext->btn_id_focused++;
            if(ext->btn_id_focused >= ext->btn_cnt - 1) ext->btn_id_focused = ext->btn_cnt - 1;
            ext->btn_id_act = ext->btn_id_focused;
            lv_obj_invalidate(btnm);
        }
        else if(c == LV_KEY_LEFT) {
            if(ext->btn_id_focused == LV_BTNMATRIX_BTN_NONE) ext->btn_id_focused = 0;
            if(ext->btn_id_focused > 0) ext->btn_id_focused--;
            ext->btn_id_act = ext->btn_id_focused;
            lv_obj_invalidate(btnm);
        }
        else if(c == LV_KEY_DOWN) {
            lv_style_int_t pad_inner = lv_obj_get_style_pad_inner(btnm, LV_BTNMATRIX_PART_BG);
            /*Find the area below the the current*/
            if(ext->btn_id_focused == LV_BTNMATRIX_BTN_NONE) {
                ext->btn_id_focused = 0;
            }
            else {
                uint16_t area_below;
                lv_coord_t pr_center =
                    ext->button_areas[ext->btn_id_focused].x1 + (lv_area_get_width(&ext->button_areas[ext->btn_id_focused]) >> 1);

                for(area_below = ext->btn_id_focused; area_below < ext->btn_cnt; area_below++) {
                    if(ext->button_areas[area_below].y1 > ext->button_areas[ext->btn_id_focused].y1 &&
                       pr_center >= ext->button_areas[area_below].x1 &&
                       pr_center <= ext->button_areas[area_below].x2 + pad_inner &&
                       button_is_inactive(ext->ctrl_bits[area_below]) == false &&
                       button_is_hidden(ext->ctrl_bits[area_below]) == false) {
                        break;
                    }
                }

                if(area_below < ext->btn_cnt) ext->btn_id_focused = area_below;
            }
            ext->btn_id_act = ext->btn_id_focused;
            lv_obj_invalidate(btnm);
        }
        else if(c == LV_KEY_UP) {
            lv_style_int_t pad_inner = lv_obj_get_style_pad_inner(btnm, LV_BTNMATRIX_PART_BG);
            /*Find the area below the the current*/
            if(ext->btn_id_focused == LV_BTNMATRIX_BTN_NONE) {
                ext->btn_id_focused = 0;
            }
            else {
                int16_t area_above;
                lv_coord_t pr_center =
                    ext->button_areas[ext->btn_id_focused].x1 + (lv_area_get_width(&ext->button_areas[ext->btn_id_focused]) >> 1);

                for(area_above = ext->btn_id_focused; area_above >= 0; area_above--) {
                    if(ext->button_areas[area_above].y1 < ext->button_areas[ext->btn_id_focused].y1 &&
                       pr_center >= ext->button_areas[area_above].x1 - pad_inner &&
                       pr_center <= ext->button_areas[area_above].x2 &&
                       button_is_inactive(ext->ctrl_bits[area_above]) == false &&
                       button_is_hidden(ext->ctrl_bits[area_above]) == false) {
                        break;
                    }
                }
                if(area_above >= 0) ext->btn_id_focused = area_above;
            }
            ext->btn_id_act = ext->btn_id_focused;
            lv_obj_invalidate(btnm);
        }
    }
    else if(sign == LV_SIGNAL_GET_EDITABLE) {
        bool * editable = (bool *)param;
        *editable       = true;
    }
    return res;
}

/**
 * Get the style descriptor of a part of the object
 * @param btnm pointer the object
 * @param part the part of the object. (LV_BTNMATRIX_PART_...)
 * @return pointer to the style descriptor of the specified part
 */
static lv_style_list_t * lv_btnmatrix_get_style(lv_obj_t * btnm, uint8_t part)
{
    LV_ASSERT_OBJ(btnm, LV_OBJX_NAME);

    lv_btnmatrix_ext_t * ext = lv_obj_get_ext_attr(btnm);

    lv_style_list_t * style_dsc_p;

    switch(part) {
        case LV_BTNMATRIX_PART_BG:
            style_dsc_p = &btnm->style_list;
            break;
        case LV_BTNMATRIX_PART_BTN:
            style_dsc_p = &ext->style_btn;
            break;
        default:
            style_dsc_p = NULL;
    }

    return style_dsc_p;
}

/**
 * Create the required number of buttons and control bytes according to a map
 * @param btnm pointer to button matrix object
 * @param map_p pointer to a string array
 */
static void allocate_btn_areas_and_controls(const lv_obj_t * btnm, const char ** map)
{
    /*Count the buttons in the map*/
    uint16_t btn_cnt = 0;
    uint16_t i       = 0;
    while(strlen(map[i]) != 0) {
        if(strcmp(map[i], "\n") != 0) { /*Do not count line breaks*/
            btn_cnt++;
        }
        i++;
    }

    lv_btnmatrix_ext_t * ext = lv_obj_get_ext_attr(btnm);

    if(ext->button_areas != NULL) {
        lv_mem_free(ext->button_areas);
        ext->button_areas = NULL;
    }
    if(ext->ctrl_bits != NULL) {
        lv_mem_free(ext->ctrl_bits);
        ext->ctrl_bits = NULL;
    }

    ext->button_areas = lv_mem_alloc(sizeof(lv_area_t) * btn_cnt);
    LV_ASSERT_MEM(ext->button_areas);
    ext->ctrl_bits = lv_mem_alloc(sizeof(lv_btnmatrix_ctrl_t) * btn_cnt);
    LV_ASSERT_MEM(ext->ctrl_bits);
    if(ext->button_areas == NULL || ext->ctrl_bits == NULL) btn_cnt = 0;

    _lv_memset_00(ext->ctrl_bits, sizeof(lv_btnmatrix_ctrl_t) * btn_cnt);

    ext->btn_cnt = btn_cnt;
}

/**
 * Get the width of a button in units (default is 1).
 * @param ctrl_bits least significant 3 bits used (1..7 valid values)
 * @return the width of the button in units
 */
static uint8_t get_button_width(lv_btnmatrix_ctrl_t ctrl_bits)
{
    uint8_t w = ctrl_bits & LV_BTNMATRIX_WIDTH_MASK;
    return w != 0 ? w : 1;
}

static bool button_is_hidden(lv_btnmatrix_ctrl_t ctrl_bits)
{
    return (ctrl_bits & LV_BTNMATRIX_CTRL_HIDDEN) ? true : false;
}

static bool button_is_repeat_disabled(lv_btnmatrix_ctrl_t ctrl_bits)
{
    return (ctrl_bits & LV_BTNMATRIX_CTRL_NO_REPEAT) ? true : false;
}

static bool button_is_inactive(lv_btnmatrix_ctrl_t ctrl_bits)
{
    return (ctrl_bits & LV_BTNMATRIX_CTRL_DISABLED) ? true : false;
}

static bool button_is_click_trig(lv_btnmatrix_ctrl_t ctrl_bits)
{
    return (ctrl_bits & LV_BTNMATRIX_CTRL_CLICK_TRIG) ? true : false;
}

static bool button_is_tgl_enabled(lv_btnmatrix_ctrl_t ctrl_bits)
{
    return (ctrl_bits & LV_BTNMATRIX_CTRL_CHECKABLE) ? true : false;
}

static bool button_get_tgl_state(lv_btnmatrix_ctrl_t ctrl_bits)
{
    return (ctrl_bits & LV_BTNMATRIX_CTRL_CHECK_STATE) ? true : false;
}

/**
 * Gives the button id of a button under a given point
 * @param btnm pointer to a button matrix object
 * @param p a point with absolute coordinates
 * @return the id of the button or LV_BTNMATRIX_BTN_NONE.
 */
static uint16_t get_button_from_point(lv_obj_t * btnm, lv_point_t * p)
{
    lv_area_t btnm_cords;
    lv_area_t btn_area;
    lv_btnmatrix_ext_t * ext = lv_obj_get_ext_attr(btnm);
    uint16_t i;
    lv_obj_get_coords(btnm, &btnm_cords);

    lv_coord_t w = lv_obj_get_width(btnm);
    lv_coord_t h = lv_obj_get_height(btnm);
    lv_style_int_t pleft = lv_obj_get_style_pad_left(btnm, LV_BTNMATRIX_PART_BG);
    lv_style_int_t pright = lv_obj_get_style_pad_right(btnm, LV_BTNMATRIX_PART_BG);
    lv_style_int_t ptop = lv_obj_get_style_pad_top(btnm, LV_BTNMATRIX_PART_BG);
    lv_style_int_t pbottom = lv_obj_get_style_pad_bottom(btnm, LV_BTNMATRIX_PART_BG);
    lv_style_int_t pinner = lv_obj_get_style_pad_inner(btnm, LV_BTNMATRIX_PART_BG);

    /*Get the half inner padding. Button look larger with this value. (+1 for rounding error)*/
    pinner = (pinner / 2) + 1 + (pinner & 1);

    for(i = 0; i < ext->btn_cnt; i++) {
        lv_area_copy(&btn_area, &ext->button_areas[i]);
        if(btn_area.x1 <= pleft) btn_area.x1 = btnm_cords.x1;
        else btn_area.x1 += btnm_cords.x1 - pinner;

        if(btn_area.y1 <= ptop) btn_area.y1 = btnm_cords.y1;
        else btn_area.y1 += btnm_cords.y1 - pinner;

        if(btn_area.x2 >= w - pright - 2) btn_area.x2 = btnm_cords.x2;  /*-2 for rounding error*/
        else btn_area.x2 += btnm_cords.x1 + pinner;

        if(btn_area.y2 >= h - pbottom - 2) btn_area.y2 = btnm_cords.y2; /*-2 for rounding error*/
        else btn_area.y2 += btnm_cords.y1 + pinner;

        if(_lv_area_is_point_on(&btn_area, p, 0) != false) {
            break;
        }
    }

    if(i == ext->btn_cnt) i = LV_BTNMATRIX_BTN_NONE;

    return i;
}

static void invalidate_button_area(const lv_obj_t * btnm, uint16_t btn_idx)
{
    if(btn_idx == LV_BTNMATRIX_BTN_NONE) return;

    lv_area_t btn_area;
    lv_area_t btnm_area;

    lv_btnmatrix_ext_t * ext = lv_obj_get_ext_attr(btnm);
    lv_area_copy(&btn_area, &ext->button_areas[btn_idx]);
    lv_obj_get_coords(btnm, &btnm_area);

    /* Convert relative coordinates to absolute */
    btn_area.x1 += btnm_area.x1;
    btn_area.y1 += btnm_area.y1;
    btn_area.x2 += btnm_area.x1;
    btn_area.y2 += btnm_area.y1;

    lv_obj_invalidate_area(btnm, &btn_area);
}

/**
 * Compares two button matrix maps for equality
 * @param map1 map to compare
 * @param map2 map to compare
 * @return true if maps are identical in length and content
 */
static bool maps_are_identical(const char ** map1, const char ** map2)
{
    if(map1 == map2) return true;
    if(map1 == NULL || map2 == NULL) return map1 == map2;

    uint16_t i = 0;
    while(map1[i][0] != '\0' && map2[i][0] != '\0') {
        if(strcmp(map1[i], map2[i]) != 0) return false;
        i++;
    }
    return map1[i][0] == '\0' && map2[i][0] == '\0';
}

/**
 * Enforces a single button being toggled on the button matrix.
 * It simply clears the toggle flag on other buttons.
 * @param btnm Button matrix object
 * @param btn_idx Button that should remain toggled
 */
static void make_one_button_toggled(lv_obj_t * btnm, uint16_t btn_idx)
{
    /*Save whether the button was toggled*/
    bool was_toggled = lv_btnmatrix_get_btn_ctrl(btnm, btn_idx, LV_BTNMATRIX_CTRL_CHECK_STATE);

    lv_btnmatrix_clear_btn_ctrl_all(btnm, LV_BTNMATRIX_CTRL_CHECK_STATE);

    if(was_toggled) lv_btnmatrix_set_btn_ctrl(btnm, btn_idx, LV_BTNMATRIX_CTRL_CHECK_STATE);
}

#endif
