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4coder/4coder_scope_commands.cpp

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Lots of new convenience features
2017-11-21 18:25:19 +00:00
/*
4coder_scope_commands.cpp - A set of commands and helpers relevant for scope level navigation and editing.
TYPE: 'drop-in-command-pack'
*/
// TOP
enum{
FindScope_Parent = 0x1,
FindScope_NextSibling = 0x1,
FindScope_EndOfToken = 0x2,
};
static bool32
find_scope_top(Application_Links *app, Buffer_Summary *buffer, int32_t start_pos, uint32_t flags, int32_t *end_pos_out){
Cpp_Get_Token_Result get_result = {0};
bool32 success = 0;
int32_t position = 0;
if (buffer_get_token_index(app, buffer, start_pos, &get_result)){
int32_t token_index = get_result.token_index;
if (flags & FindScope_Parent){
--token_index;
if (get_result.in_whitespace){
++token_index;
}
}
if (token_index >= 0){
static const int32_t chunk_cap = 512;
Cpp_Token chunk[chunk_cap];
Stream_Tokens stream = {0};
if (init_stream_tokens(&stream, app, buffer, token_index, chunk, chunk_cap)){int32_t nest_level = 0;
bool32 still_looping = 0;
do{
for (; token_index >= stream.start; --token_index){
Cpp_Token *token = &stream.tokens[token_index];
switch (token->type){
case CPP_TOKEN_BRACE_OPEN:
{
if (nest_level == 0){
success = 1;
position = token->start;
if (flags & FindScope_EndOfToken){
position += token->size;
}
goto finished;
}
else{
--nest_level;
}
}break;
case CPP_TOKEN_BRACE_CLOSE:
{
++nest_level;
}break;
}
}
still_looping = backward_stream_tokens(&stream);
}while(still_looping);
}
}
}
finished:;
*end_pos_out = position;
return(success);
}
static bool32
find_scope_bottom(Application_Links *app, Buffer_Summary *buffer, int32_t start_pos, uint32_t flags, int32_t *end_pos_out){
Cpp_Get_Token_Result get_result = {0};
bool32 success = 0;
int32_t position = 0;
if (buffer_get_token_index(app, buffer, start_pos, &get_result)){
int32_t token_index = get_result.token_index+1;
if (flags & FindScope_Parent){
--token_index;
if (get_result.in_whitespace){
++token_index;
}
}
if (token_index >= 0){
static const int32_t chunk_cap = 512;
Cpp_Token chunk[chunk_cap];
Stream_Tokens stream = {0};
if (init_stream_tokens(&stream, app, buffer, token_index, chunk, chunk_cap)){
int32_t nest_level = 0;
bool32 still_looping = 0;
do{
for (; token_index < stream.end; ++token_index){
Cpp_Token *token = &stream.tokens[token_index];
switch (token->type){
case CPP_TOKEN_BRACE_OPEN:
{
++nest_level;
}break;
case CPP_TOKEN_BRACE_CLOSE:
{
if (nest_level == 0){
success = 1;
position = token->start;
if (flags & FindScope_EndOfToken){
position += token->size;
}
goto finished;
}
else{
--nest_level;
}
}break;
}
}
still_looping = forward_stream_tokens(&stream);
}while(still_looping);
}
}
}
finished:;
*end_pos_out = position;
return(success);
}
static bool32
find_next_scope(Application_Links *app, Buffer_Summary *buffer, int32_t start_pos, uint32_t flags, int32_t *end_pos_out){
Cpp_Get_Token_Result get_result = {0};
bool32 success = 0;
int32_t position = 0;
if (buffer_get_token_index(app, buffer, start_pos, &get_result)){
int32_t token_index = get_result.token_index+1;
if (token_index >= 0){
static const int32_t chunk_cap = 512;
Cpp_Token chunk[chunk_cap];
Stream_Tokens stream = {0};
if (init_stream_tokens(&stream, app, buffer, token_index, chunk, chunk_cap)){
if (flags & FindScope_NextSibling){
int32_t nest_level = 1;
bool32 still_looping = 0;
do{
for (; token_index < stream.end; ++token_index){
Cpp_Token *token = &stream.tokens[token_index];
switch (token->type){
case CPP_TOKEN_BRACE_OPEN:
{
if (nest_level == 0){
success = 1;
position = token->start;
if (flags & FindScope_EndOfToken){
position += token->size;
}
goto finished;
}
else{
++nest_level;
}
}break;
case CPP_TOKEN_BRACE_CLOSE:
{
--nest_level;
if (nest_level == -1){
position = start_pos;
goto finished;
}
}break;
}
}
still_looping = forward_stream_tokens(&stream);
}while(still_looping);
}
else{
bool32 still_looping = 0;
do{
for (; token_index < stream.end; ++token_index){
Cpp_Token *token = &stream.tokens[token_index];
if (token->type == CPP_TOKEN_BRACE_OPEN){
success = 1;
position = token->start;
if (flags & FindScope_EndOfToken){
position += token->size;
}
goto finished;
}
}
still_looping = forward_stream_tokens(&stream);
}while(still_looping);
}
}
}
}
finished:;
*end_pos_out = position;
return(success);
}
static bool32
find_prev_scope(Application_Links *app, Buffer_Summary *buffer, int32_t start_pos, uint32_t flags, int32_t *end_pos_out){
Cpp_Get_Token_Result get_result = {0};
bool32 success = 0;
int32_t position = 0;
if (buffer_get_token_index(app, buffer, start_pos, &get_result)){
int32_t token_index = get_result.token_index-1;
if (token_index >= 0){
static const int32_t chunk_cap = 512;
Cpp_Token chunk[chunk_cap];
Stream_Tokens stream = {0};
if (init_stream_tokens(&stream, app, buffer, token_index, chunk, chunk_cap)){
if (flags & FindScope_NextSibling){
int32_t nest_level = -1;
bool32 still_looping = 0;
do{
for (; token_index >= stream.start; --token_index){
Cpp_Token *token = &stream.tokens[token_index];
switch (token->type){
case CPP_TOKEN_BRACE_OPEN:
{
if (nest_level == -1){
position = start_pos;
goto finished;
}
else if (nest_level == 0){
success = 1;
position = token->start;
if (flags & FindScope_EndOfToken){
position += token->size;
}
goto finished;
}
else{
--nest_level;
}
}break;
case CPP_TOKEN_BRACE_CLOSE:
{
++nest_level;
}break;
}
}
still_looping = backward_stream_tokens(&stream);
}while(still_looping);
}
else{
bool32 still_looping = 0;
do{
for (; token_index >= stream.start; --token_index){
Cpp_Token *token = &stream.tokens[token_index];
if (token->type == CPP_TOKEN_BRACE_OPEN){
success = 1;
position = token->start;
if (flags & FindScope_EndOfToken){
position += token->size;
}
goto finished;
}
}
still_looping = backward_stream_tokens(&stream);
}while(still_looping);
}
}
}
}
finished:;
*end_pos_out = position;
return(success);
}
static void
view_set_to_region(Application_Links *app, View_Summary *view, int32_t major_pos, int32_t minor_pos, float normalized_threshold){
Range range = make_range(major_pos, minor_pos);
bool32 bottom_major = false;
if (major_pos == range.max){
bottom_major = true;
}
Full_Cursor top, bottom;
if (view_compute_cursor(app, view, seek_pos(range.min), &top)){
if (view_compute_cursor(app, view, seek_pos(range.max), &bottom)){
float top_y = top.wrapped_y;
float bottom_y = bottom.wrapped_y;
if (view->unwrapped_lines){
top_y = top.unwrapped_y;
bottom_y = bottom.unwrapped_y;
}
GUI_Scroll_Vars scroll = view->scroll_vars;
float half_view_height = .5f*(float)(view->file_region.y1 - view->file_region.y0);
float threshold = normalized_threshold * half_view_height;
float current_center_y = ((float)scroll.target_y) + half_view_height;
if (top_y < current_center_y - threshold || bottom_y > current_center_y + threshold){
float center_target_y = .5f*(top_y + bottom_y);
if (bottom_major){
if (center_target_y < bottom_y - half_view_height * .9f){
center_target_y = bottom_y - half_view_height * .9f;
}
}
else{
if (center_target_y > top_y + half_view_height * .9f){
center_target_y = top_y + half_view_height * .9f;
}
}
float target_y = center_target_y - half_view_height;
if (target_y < 0){
target_y = 0;
}
scroll.target_y = (int32_t)(target_y);
view_set_scroll(app, view, scroll);
}
}
}
}
static float scope_center_threshold = 0.75f;
CUSTOM_COMMAND_SIG(highlight_surrounding_scope)
CUSTOM_DOC("Finds the scope enclosed by '{' '}' surrounding the cursor and puts the cursor and mark on the '{' and '}'.")
{
uint32_t access = AccessProtected;
View_Summary view = get_active_view(app, access);
Buffer_Summary buffer = get_buffer(app, view.buffer_id, access);
int32_t start_pos = view.cursor.pos;
Fixing indentation bugs with new tricks
2017-11-28 23:31:10 +00:00
int32_t top = 0;
int32_t bottom = 0;
Lots of new convenience features
2017-11-21 18:25:19 +00:00
if (find_scope_top(app, &buffer, start_pos, FindScope_Parent, &top)){
view_set_cursor(app, &view, seek_pos(top), true);
if (find_scope_bottom(app, &buffer, start_pos, FindScope_Parent | FindScope_EndOfToken, &bottom)){
view_set_mark(app, &view, seek_pos(bottom));
view_set_to_region(app, &view, top, bottom, scope_center_threshold);
}
else{
view_set_to_region(app, &view, top, top, scope_center_threshold);
}
}
}
CUSTOM_COMMAND_SIG(highlight_next_scope_absolute)
CUSTOM_DOC("Finds the first scope started by '{' after the cursor and puts the cursor and mark on the '{' and '}'.")
{
uint32_t access = AccessProtected;
View_Summary view = get_active_view(app, access);
Buffer_Summary buffer = get_buffer(app, view.buffer_id, access);
int32_t start_pos = view.cursor.pos;
Fixing indentation bugs with new tricks
2017-11-28 23:31:10 +00:00
int32_t top = 0;
int32_t bottom = 0;
Lots of new convenience features
2017-11-21 18:25:19 +00:00
if (find_next_scope(app, &buffer, start_pos, 0, &top)){
if (find_scope_bottom(app, &buffer, top, FindScope_EndOfToken, &bottom)){
view_set_cursor(app, &view, seek_pos(top), true);
view_set_mark(app, &view, seek_pos(bottom));
view_set_to_region(app, &view, top, bottom, scope_center_threshold);
}
}
}
CUSTOM_COMMAND_SIG(highlight_prev_scope_absolute)
CUSTOM_DOC("Finds the first scope started by '{' before the cursor and puts the cursor and mark on the '{' and '}'.")
{
uint32_t access = AccessProtected;
View_Summary view = get_active_view(app, access);
Buffer_Summary buffer = get_buffer(app, view.buffer_id, access);
int32_t start_pos = view.cursor.pos;
int32_t top = 0, bottom = 0;
if (find_prev_scope(app, &buffer, start_pos, 0, &top)){
if (find_scope_bottom(app, &buffer, top, FindScope_EndOfToken, &bottom)){
view_set_cursor(app, &view, seek_pos(top), true);
view_set_mark(app, &view, seek_pos(bottom));
view_set_to_region(app, &view, top, bottom, scope_center_threshold);
}
}
}
Lots and lots of new commands, and sharpened up some other stuff too
2017-11-29 23:00:14 +00:00
static void
place_begin_and_end_on_own_lines(Application_Links *app, Partition *scratch, char *begin, char *end){
View_Summary view = get_active_view(app, AccessOpen);
Buffer_Summary buffer = get_buffer(app, view.buffer_id, AccessOpen);
Lots of new convenience features
2017-11-21 18:25:19 +00:00
Cleaning up linex_index -> line_number naming
2017-11-28 20:16:53 +00:00
Range lines = {0};
Lots of new convenience features
2017-11-21 18:25:19 +00:00
Range range = get_range(&view);
Cleaning up linex_index -> line_number naming
2017-11-28 20:16:53 +00:00
lines.min = buffer_get_line_number(app, &buffer, range.min);
Lots of new convenience features
2017-11-21 18:25:19 +00:00
range.min = buffer_get_line_start(app, &buffer, lines.min);
Cleaning up linex_index -> line_number naming
2017-11-28 20:16:53 +00:00
lines.max = buffer_get_line_number(app, &buffer, range.max);
Lots of new convenience features
2017-11-21 18:25:19 +00:00
range.max = buffer_get_line_end(app, &buffer, lines.max);
Cleaning up linex_index -> line_number naming
2017-11-28 20:16:53 +00:00
bool32 do_full = (lines.min < lines.max) || (!buffer_line_is_blank(app, &buffer, lines.min));
Lots of new convenience features
2017-11-21 18:25:19 +00:00
Lots and lots of new commands, and sharpened up some other stuff too
2017-11-29 23:00:14 +00:00
Temp_Memory temp = begin_temp_memory(scratch);
int32_t begin_len = str_size(begin);
int32_t end_len = str_size(end);
int32_t str_size = begin_len + end_len + 2;
char *str = push_array(scratch, char, str_size);
String builder = make_string_cap(str, 0, str_size);
append(&builder, begin);
append(&builder, "\n");
append(&builder, "\n");
append(&builder, end);
Lots of new convenience features
2017-11-21 18:25:19 +00:00
if (do_full){
Buffer_Edit edits[2];
int32_t min_adjustment = 0;
int32_t max_adjustment = 4;
if (buffer_line_is_blank(app, &buffer, lines.min)){
Lots and lots of new commands, and sharpened up some other stuff too
2017-11-29 23:00:14 +00:00
memmove(str + 1, str, begin_len);
Lots of new convenience features
2017-11-21 18:25:19 +00:00
str[0] = '\n';
++min_adjustment;
}
if (buffer_line_is_blank(app, &buffer, lines.max)){
Lots and lots of new commands, and sharpened up some other stuff too
2017-11-29 23:00:14 +00:00
memmove(str + begin_len + 1, str + begin_len + 2, end_len);
str[begin_len + end_len + 1] = '\n';
Lots of new convenience features
2017-11-21 18:25:19 +00:00
--max_adjustment;
}
int32_t min_pos = range.min + min_adjustment;
int32_t max_pos = range.max + max_adjustment;
int32_t cursor_pos = min_pos;
int32_t mark_pos = max_pos;
if (view.cursor.pos > view.mark.pos){
cursor_pos = max_pos;
mark_pos = min_pos;
}
edits[0].str_start = 0;
Lots and lots of new commands, and sharpened up some other stuff too
2017-11-29 23:00:14 +00:00
edits[0].len = begin_len + 1;
Lots of new convenience features
2017-11-21 18:25:19 +00:00
edits[0].start = range.min;
edits[0].end = range.min;
Lots and lots of new commands, and sharpened up some other stuff too
2017-11-29 23:00:14 +00:00
edits[1].str_start = begin_len + 1;
edits[1].len = end_len + 1;
Lots of new convenience features
2017-11-21 18:25:19 +00:00
edits[1].start = range.max;
edits[1].end = range.max;
Lots and lots of new commands, and sharpened up some other stuff too
2017-11-29 23:00:14 +00:00
buffer_batch_edit(app, &buffer, str, str_size, edits, 2, BatchEdit_Normal);
Lots of new convenience features
2017-11-21 18:25:19 +00:00
view_set_cursor(app, &view, seek_pos(cursor_pos), true);
view_set_mark(app, &view, seek_pos(mark_pos));
}
else{
Lots and lots of new commands, and sharpened up some other stuff too
2017-11-29 23:00:14 +00:00
buffer_replace_range(app, &buffer, range.min, range.max, str, str_size);
int32_t center_pos = range.min + begin_len + 1;
view_set_cursor(app, &view, seek_pos(center_pos), true);
view_set_mark(app, &view, seek_pos(center_pos));
Lots of new convenience features
2017-11-21 18:25:19 +00:00
}
Lots and lots of new commands, and sharpened up some other stuff too
2017-11-29 23:00:14 +00:00
end_temp_memory(temp);
}
CUSTOM_COMMAND_SIG(place_in_scope)
CUSTOM_DOC("Wraps the code contained in the range between cursor and mark with a new curly brace scope.")
{
place_begin_and_end_on_own_lines(app, &global_part, "{", "}");
Lots of new convenience features
2017-11-21 18:25:19 +00:00
}
CUSTOM_COMMAND_SIG(delete_current_scope)
CUSTOM_DOC("Deletes the braces surrounding the currently selected scope. Leaves the contents within the scope.")
{
uint32_t access = AccessOpen;
View_Summary view = get_active_view(app, access);
Buffer_Summary buffer = get_buffer(app, view.buffer_id, access);
int32_t top = view.cursor.pos;
int32_t bottom = view.mark.pos;
if (top > bottom){
int32_t x = top;
top = bottom;
bottom = x;
}
if (buffer_get_char(app, &buffer, top) == '{' && buffer_get_char(app, &buffer, bottom-1) == '}'){
int32_t top_len = 1;
int32_t bottom_len = 1;
if (buffer_get_char(app, &buffer, top-1) == '\n'){
top_len = 2;
}
if (buffer_get_char(app, &buffer, bottom+1) == '\n'){
bottom_len = 2;
}
Buffer_Edit edits[2];
edits[0].str_start = 0;
edits[0].len = 0;
edits[0].start = top+1 - top_len;
edits[0].end = top+1;
edits[1].str_start = 0;
edits[1].len = 0;
edits[1].start = bottom-1;
edits[1].end = bottom-1 + bottom_len;
buffer_batch_edit(app, &buffer, 0, 0, edits, 2, BatchEdit_Normal);
}
}
struct Statement_Parser{
Stream_Tokens stream;
int32_t token_index;
Buffer_Summary *buffer;
};
static Cpp_Token*
parser_next_token(Statement_Parser *parser){
Cpp_Token *result = 0;
bool32 still_looping = true;
while (parser->token_index >= parser->stream.end && still_looping){
still_looping = forward_stream_tokens(&parser->stream);
}
if (parser->token_index < parser->stream.end){
result = &parser->stream.tokens[parser->token_index];
++parser->token_index;
}
return(result);
}
static bool32 parse_statement_down(Application_Links *app, Statement_Parser *parser, Cpp_Token *token_out);
static bool32
parse_for_down(Application_Links *app, Statement_Parser *parser, Cpp_Token *token_out){
bool32 success = false;
Cpp_Token *token = parser_next_token(parser);
int32_t paren_level = 0;
while (token != 0){
if (!(token->flags & CPP_TFLAG_PP_BODY)){
switch (token->type){
case CPP_TOKEN_PARENTHESE_OPEN:
{
++paren_level;
}break;
case CPP_TOKEN_PARENTHESE_CLOSE:
{
--paren_level;
if (paren_level == 0){
success = parse_statement_down(app, parser, token_out);
goto finished;
}
else if (paren_level < 0){
success = false;
goto finished;
}
}break;
}
}
token = parser_next_token(parser);
}
finished:;
return(success);
}
static bool32
parse_if_down(Application_Links *app, Statement_Parser *parser, Cpp_Token *token_out){
bool32 success = false;
Cpp_Token *token = parser_next_token(parser);
if (token != 0){
success = parse_statement_down(app, parser, token_out);
if (success){
token = parser_next_token(parser);
if (token != 0 && token->type == CPP_TOKEN_KEY_CONTROL_FLOW){
char lexeme[32];
if (sizeof(lexeme)-1 >= token->size){
if (buffer_read_range(app, parser->buffer, token->start, token->start + token->size, lexeme)){
lexeme[token->size] = 0;
if (match(lexeme, "else")){
success = parse_statement_down(app, parser, token_out);
}
}
}
}
}
}
return(success);
}
static bool32
parse_block_down(Application_Links *app, Statement_Parser *parser, Cpp_Token *token_out){
bool32 success = false;
Cpp_Token *token = parser_next_token(parser);
int32_t nest_level = 0;
while (token != 0){
switch (token->type){
case CPP_TOKEN_BRACE_OPEN:
{
++nest_level;
}break;
case CPP_TOKEN_BRACE_CLOSE:
{
if (nest_level == 0){
*token_out = *token;
success = true;
goto finished;
}
--nest_level;
}break;
}
token = parser_next_token(parser);
}
finished:;
return(success);
}
static bool32
parse_statement_down(Application_Links *app, Statement_Parser *parser, Cpp_Token *token_out){
bool32 success = false;
Cpp_Token *token = parser_next_token(parser);
if (token != 0){
bool32 not_getting_block = false;
do{
switch (token->type){
case CPP_TOKEN_BRACE_CLOSE:
{
goto finished;
}break;
case CPP_TOKEN_KEY_CONTROL_FLOW:
{
char lexeme[32];
if (sizeof(lexeme)-1 >= token->size){
if (buffer_read_range(app, parser->buffer, token->start, token->start + token->size, lexeme)){
lexeme[token->size] = 0;
if (match(lexeme, "for")){
success = parse_for_down(app, parser, token_out);
goto finished;
}
else if (match(lexeme, "if")){
success = parse_if_down(app, parser, token_out);
goto finished;
}
else if (match(lexeme, "else")){
success = false;
goto finished;
}
}
}
}break;
case CPP_TOKEN_BRACE_OPEN:
{
if (!not_getting_block){
success = parse_block_down(app, parser, token_out);
goto finished;
}
}break;
case CPP_TOKEN_SEMICOLON:
{
success = true;
*token_out = *token;
goto finished;
}break;
case CPP_TOKEN_EQ:
{
not_getting_block = true;
}break;
}
token = parser_next_token(parser);
}while(token != 0);
}
finished:;
return(success);
}
static bool32
find_whole_statement_down(Application_Links *app, Buffer_Summary *buffer, int32_t pos, int32_t *start_out, int32_t *end_out){
bool32 result = false;
int32_t start = pos;
int32_t end = start;
Cpp_Get_Token_Result get_result = {0};
if (buffer_get_token_index(app, buffer, pos, &get_result)){
Statement_Parser parser = {0};
parser.token_index = get_result.token_index;
if (parser.token_index < 0){
parser.token_index = 0;
}
if (get_result.in_whitespace){
parser.token_index += 1;
}
static const int32_t chunk_cap = 512;
Cpp_Token chunk[chunk_cap];
if (init_stream_tokens(&parser.stream, app, buffer, parser.token_index, chunk, chunk_cap)){
parser.buffer = buffer;
Cpp_Token end_token = {0};
if (parse_statement_down(app, &parser, &end_token)){
end = end_token.start + end_token.size;
result = true;
}
}
}
*start_out = start;
*end_out = end;
return(result);
}
CUSTOM_COMMAND_SIG(scope_absorb_down)
CUSTOM_DOC("If a scope is currently selected, and a statement or block statement is present below the current scope, the statement is moved into the scope.")
{
uint32_t access = AccessOpen;
View_Summary view = get_active_view(app, access);
Buffer_Summary buffer = get_buffer(app, view.buffer_id, access);
int32_t top = view.cursor.pos;
int32_t bottom = view.mark.pos;
if (top > bottom){
int32_t x = top;
top = bottom;
bottom = x;
}
Partition *part = &global_part;
Temp_Memory temp = begin_temp_memory(part);
if (buffer_get_char(app, &buffer, top) == '{' && buffer_get_char(app, &buffer, bottom-1) == '}'){
Range range;
if (find_whole_statement_down(app, &buffer, bottom, &range.start, &range.end)){
char *string_space = push_array(part, char, range.end - range.start);
buffer_read_range(app, &buffer, range.start, range.end, string_space);
String string = make_string(string_space, range.end - range.start);
string = skip_chop_whitespace(string);
int32_t newline_count = 0;
for (char *ptr = string_space; ptr < string.str; ++ptr){
if (*ptr == '\n'){
++newline_count;
}
}
bool32 extra_newline = false;
if (newline_count >= 2){
extra_newline = true;
}
int32_t edit_len = string.size + 1;
if (extra_newline){
edit_len += 1;
}
char *edit_str = push_array(part, char, edit_len);
if (extra_newline){
edit_str[0] = '\n';
copy_fast_unsafe(edit_str+1, string);
edit_str[edit_len-1] = '\n';
}
else{
copy_fast_unsafe(edit_str, string);
edit_str[edit_len-1] = '\n';
}
Buffer_Edit edits[2];
edits[0].str_start = 0;
edits[0].len = edit_len;
edits[0].start = bottom-1;
edits[0].end = bottom-1;
edits[1].str_start = 0;
edits[1].len = 0;
edits[1].start = range.start;
edits[1].end = range.end;
buffer_batch_edit(app, &buffer, edit_str, edit_len, edits, 2, BatchEdit_Normal);
}
}
end_temp_memory(temp);
}
// BOTTOM