From 143bbfc133e1a189c9f99cfffe41c4397b677f39 Mon Sep 17 00:00:00 2001 From: Leo Tenenbaum Date: Sat, 19 Dec 2020 19:26:15 -0500 Subject: more undo --- buffer.c | 103 ++++++++++++++++++++++++++++++++++++++++++++++++--------------- 1 file changed, 79 insertions(+), 24 deletions(-) (limited to 'buffer.c') diff --git a/buffer.c b/buffer.c index cfc8880..d8cb6fe 100644 --- a/buffer.c +++ b/buffer.c @@ -108,15 +108,40 @@ static void *buffer_realloc(TextBuffer *buffer, void *p, size_t new_size) { return ret; } -static WarnUnusedResult BufferEdit *buffer_edit_delete_line(TextBuffer *buffer, u32 line, bool join_with_next) { - BufferEdit *e = buffer_calloc(buffer, 1, sizeof *e); +static WarnUnusedResult BufferEdit *buffer_edit_delete_line(TextBuffer *buffer, u32 line, char32_t const *prev_str, u32 prev_str_len, bool join_with_next) { + BufferEdit *e = buffer_calloc(buffer, 1, sizeof *e + prev_str_len * sizeof *prev_str); if (e) { e->type = BUFFER_EDIT_DELETE_LINE; e->line = line; e->join_with_next = join_with_next; + e->prev_str_len = prev_str_len; + memcpy(e->prev_str, prev_str, prev_str_len * sizeof *prev_str); + } + return e; +} + +static WarnUnusedResult BufferEdit *buffer_edit_insert_line(TextBuffer *buffer, u32 line, bool join_with_next) { + BufferEdit *e = buffer_calloc(buffer, 1, sizeof *e); + if (e) { + e->type = BUFFER_EDIT_INSERT_LINE; + e->line = line; + e->join_with_next = join_with_next; + } + return e; +} + +static WarnUnusedResult BufferEdit *buffer_edit_change_line(TextBuffer *buffer, u32 line, char32_t const *prev_str, u32 prev_str_len, bool join_with_next) { + BufferEdit *e = buffer_calloc(buffer, 1, sizeof *e + prev_str_len * sizeof *prev_str); + if (e) { + e->type = BUFFER_EDIT_CHANGE_LINE; + e->line = line; + e->join_with_next = join_with_next; + e->prev_str_len = prev_str_len; + memcpy(e->prev_str, prev_str, prev_str_len * sizeof *prev_str); } return e; } + // grow capacity of line to at least minimum_capacity // returns true if allocation was succesful static Status buffer_line_grow(TextBuffer *buffer, Line *line, u32 minimum_capacity) { @@ -939,6 +964,19 @@ static void buffer_shorten(TextBuffer *buffer, u32 new_nlines) { buffer->nlines = new_nlines; // @OPTIMIZE(memory): decrease lines capacity } +// delete `nlines` lines starting from index `first_line_idx` +void buffer_delete_lines(TextBuffer *buffer, u32 first_line_idx, u32 nlines) { + assert(first_line_idx < buffer->nlines); + assert(first_line_idx+nlines < buffer->nlines); + Line *first_line = &buffer->lines[first_line_idx]; + Line *end = first_line + nlines; + + for (Line *l = first_line; l != end; ++l) { + buffer_line_free(l); + } + memmove(first_line, end, (size_t)(buffer->lines + buffer->nlines - end) * sizeof(Line)); +} + void buffer_delete_chars_at_pos(TextBuffer *buffer, BufferPos pos, i64 nchars) { u32 line_idx = pos.line; u32 index = pos.index; @@ -965,11 +1003,8 @@ void buffer_delete_chars_at_pos(TextBuffer *buffer, BufferPos pos, i64 nchars) { line->len += last_line_chars_left; } // remove all lines between line + 1 and last_line (inclusive). - for (Line *l = line + 1; l <= last_line; ++l) { - buffer_line_free(l); - } - // @TODO: test with removing more than one line - memmove(line + 1, last_line + 1, (size_t)(lines_end - (last_line + 1)) * sizeof *line); + buffer_delete_lines(buffer, line_idx + 1, (u32)(last_line - line)); + u32 lines_removed = (u32)(last_line - line); buffer_shorten(buffer, buffer->nlines - lines_removed); } @@ -1032,23 +1067,43 @@ void buffer_backspace_words_at_cursor(TextBuffer *buffer, i64 nwords) { static void buffer_undo(TextBuffer *buffer, i64 ntimes) { for (i64 i = 0; i < ntimes; ++i) { - BufferEdit *edit = buffer->undo_history; - BufferEdit *inverse = NULL; - switch (edit->type) { - case BUFFER_EDIT_DELETE_LINE: { - // let's re-insert that line - buffer_insert_lines(buffer, edit->line, 1); - BufferPos pos = {.line = edit->line, .index = 0}; - String32 str = {edit->prev_str_len, edit->prev_str}; - buffer_insert_text_at_pos(buffer, pos, str); - inverse = buffer_calloc(buffer, 1, sizeof *inverse); - - } break; - } - assert(inverse); - buffer->undo_history = edit->next; - inverse->next = buffer->redo_history; - buffer->redo_history = inverse; + bool join_with_next; + do { + BufferEdit *edit = buffer->undo_history; + join_with_next = edit->join_with_next; // should the next edit be undone along with this one? + BufferEdit *inverse = NULL; + switch (edit->type) { + case BUFFER_EDIT_DELETE_LINE: { + // let's re-insert that line + buffer_insert_lines(buffer, edit->line, 1); + BufferPos pos = {.line = edit->line, .index = 0}; + String32 str = {edit->prev_str_len, edit->prev_str}; + buffer_insert_text_at_pos(buffer, pos, str); + inverse = buffer_edit_insert_line(buffer, edit->line, join_with_next); + } break; + case BUFFER_EDIT_INSERT_LINE: { + Line *line = &buffer->lines[edit->line]; + inverse = buffer_edit_delete_line(buffer, edit->line, line->str, line->len, join_with_next); + // delete that line + buffer_delete_lines(buffer, edit->line, 1); + } break; + case BUFFER_EDIT_CHANGE_LINE: { + Line *line = &buffer->lines[edit->line]; + inverse = buffer_edit_change_line(buffer, edit->line, line->str, line->len, join_with_next); + if (buffer_line_grow(buffer, line, edit->prev_str_len)) { + line->len = edit->prev_str_len; + memcpy(line->str, edit->prev_str, edit->prev_str_len * sizeof(char32_t)); + } + } break; + } + + assert(inverse); + buffer->undo_history = edit->next; + inverse->next = buffer->redo_history; + buffer->redo_history = inverse; + + free(edit); + } while (join_with_next); } } -- cgit v1.2.3