diff options
Diffstat (limited to 'buffer.c')
| -rw-r--r-- | buffer.c | 36 |
1 files changed, 27 insertions, 9 deletions
@@ -18,7 +18,7 @@ typedef struct BufferEdit { u32 new_len; u32 prev_len; char32_t *prev_text; - double time; // time in seconds since epoch + double time; // time at start of edit (i.e. the time just before the edit), in seconds since epoch } BufferEdit; typedef struct { @@ -288,6 +288,7 @@ static void buffer_pos_print(BufferPos p) { } static Status buffer_edit_create(TextBuffer *buffer, BufferEdit *edit, BufferPos start, u32 prev_len, u32 new_len) { + edit->time = time_get_seconds(); if (prev_len == 0) edit->prev_text = NULL; // if there's no previous text, don't allocate anything else @@ -372,6 +373,15 @@ static bool buffer_edit_does_anything(TextBuffer *buffer, BufferEdit *edit) { } } +// has enough time passed since the last edit that we should create a new one? +static bool buffer_edit_split(TextBuffer *buffer) { + double curr_time = time_get_seconds(); + double undo_time_cutoff = 6.0; // only keep around edits for this long (in seconds). @SETTINGS + BufferEdit *last_edit = arr_lastp(buffer->undo_history); + if (!last_edit) return true; + return curr_time - last_edit->time > undo_time_cutoff; +} + // removes the last edit in the undo history if it doesn't do anything static void buffer_remove_last_edit_if_empty(TextBuffer *buffer) { if (buffer->store_undo_events) { @@ -1106,12 +1116,16 @@ BufferPos buffer_insert_text_at_pos(TextBuffer *buffer, BufferPos pos, String32 if (buffer->store_undo_events) { BufferEdit *last_edit = arr_lastp(buffer->undo_history); i64 where_in_last_edit = last_edit ? buffer_pos_diff(buffer, last_edit->pos, pos) : -1; - if (where_in_last_edit >= 0 && where_in_last_edit <= (i64)last_edit->new_len) { - // merge this edit into the previous one. - last_edit->new_len += str.len; - } else { + // create a new edit, rather than adding to the old one if: + bool create_new_edit = where_in_last_edit < 0 || where_in_last_edit > last_edit->new_len // insertion is happening outside the previous edit, + || buffer_edit_split(buffer); // or enough time has elapsed to warrant a new one. + + if (create_new_edit) { // create a new edit for this insertion buffer_edit(buffer, pos, 0, (u32)str.len); + } else { + // merge this edit into the previous one. + last_edit->new_len += str.len; } } @@ -1249,7 +1263,9 @@ void buffer_delete_chars_at_pos(TextBuffer *buffer, BufferPos pos, i64 nchars_) bool create_new_edit = !last_edit || // if there is no previous edit to combine it with buffer_pos_cmp(del_end, edit_start) < 0 || // or if delete does not overlap last_edit - buffer_pos_cmp(del_start, edit_end) > 0; + buffer_pos_cmp(del_start, edit_end) > 0 || + buffer_edit_split(buffer); // or if enough time has passed to warrant a new edit + if (create_new_edit) { // create a new edit buffer_edit(buffer, pos, nchars, 0); @@ -1261,7 +1277,7 @@ void buffer_delete_chars_at_pos(TextBuffer *buffer, BufferPos pos, i64 nchars_) u32 updated_prev_len = (u32)(chars_before_edit + last_edit->prev_len); if (buffer_edit_resize_prev_text(buffer, last_edit, updated_prev_len)) { // make space - memmove(last_edit->prev_text + chars_before_edit, last_edit->prev_text, last_edit->prev_len); + memmove(last_edit->prev_text + chars_before_edit, last_edit->prev_text, last_edit->prev_len * sizeof(char32_t)); // prepend these chracters to the edit's text buffer_get_text_at_pos(buffer, del_start, last_edit->prev_text, (size_t)chars_before_edit); @@ -1287,8 +1303,10 @@ void buffer_delete_chars_at_pos(TextBuffer *buffer, BufferPos pos, i64 nchars_) if (new_text_del_start < 0) new_text_del_start = 0; i64 new_text_del_end = buffer_pos_diff(buffer, edit_start, del_end); if (new_text_del_end > last_edit->new_len) new_text_del_end = last_edit->new_len; - // shrink length to get rid of that text - last_edit->new_len -= new_text_del_end - new_text_del_start; + if (new_text_del_end > new_text_del_start) { + // shrink length to get rid of that text + last_edit->new_len -= new_text_del_end - new_text_del_start; + } } } |