diff options
| -rw-r--r-- | buffer.c | 82 | ||||
| -rw-r--r-- | main.c | 10 |
2 files changed, 84 insertions, 8 deletions
@@ -471,6 +471,40 @@ static void buffer_pos_validate(TextBuffer *buffer, BufferPos *p) { p->index = line_len; } +static bool buffer_pos_valid(TextBuffer *buffer, BufferPos p) { + return p.line < buffer->nlines && p.index <= buffer->lines[p.line].len; +} + +// returns "p2 - p1", that is, the number of characters between p1 and p2. +static i64 buffer_pos_diff(TextBuffer *buffer, BufferPos p1, BufferPos p2) { + assert(buffer_pos_valid(buffer, p1)); + assert(buffer_pos_valid(buffer, p2)); + + if (p1.line == p2.line) { + // p1 and p2 are in the same line + return (i64)p2.index - p1.index; + } + i64 factor = 1; + if (p1.line > p2.line) { + // switch positions so p2 has the later line + BufferPos tmp = p1; + p1 = p2; + p2 = tmp; + factor = -1; + } + + assert(p2.line > p1.line); + i64 chars_at_end_of_p1_line = buffer->lines[p1.line].len - p1.index + 1; // + 1 for newline + i64 chars_at_start_of_p2_line = p2.index; + i64 chars_in_lines_in_between = 0; + // now we need to add up the lengths of the lines between p1 and p2 + for (Line *line = buffer->lines + (p1.line + 1), *end = buffer->lines + p2.line; line != end; ++line) { + chars_in_lines_in_between += line->len; + } + i64 total = chars_at_end_of_p1_line + chars_in_lines_in_between + chars_at_start_of_p2_line; + return total * factor; +} + // move left (if `by` is negative) or right (if `by` is positive) by the specified amount. // returns the signed number of characters successfully moved (it could be less in magnitude than `by` if the beginning of the file is reached) i64 buffer_pos_move_horizontally(TextBuffer *buffer, BufferPos *p, i64 by) { @@ -772,7 +806,6 @@ BufferPos buffer_insert_text_at_pos(TextBuffer *buffer, BufferPos pos, String32 return b; } - void buffer_insert_text_at_cursor(TextBuffer *buffer, String32 str) { buffer->cursor_pos = buffer_insert_text_at_pos(buffer, buffer->cursor_pos, str); buffer_scroll_to_cursor(buffer); @@ -815,7 +848,6 @@ void buffer_delete_chars_at_pos(TextBuffer *buffer, BufferPos pos, i64 nchars) { nchars -= last_line->len+1; } if (last_line == lines_end) { - // @TODO: test this // delete everything to the end of the file for (u32 idx = line_idx + 1; idx < buffer->nlines; ++idx) { buffer_line_free(&buffer->lines[idx]); @@ -842,16 +874,54 @@ void buffer_delete_chars_at_pos(TextBuffer *buffer, BufferPos pos, i64 nchars) { memmove(line->str + index, line->str + index + nchars, (size_t)(line->len - (nchars + index)) * sizeof(char32_t)); line->len -= (u32)nchars; } +} +// Delete characters between the given buffer positions. +void buffer_delete_chars_between(TextBuffer *buffer, BufferPos p1, BufferPos p2) { + buffer_pos_validate(buffer, &p1); + buffer_pos_validate(buffer, &p2); + i64 nchars = buffer_pos_diff(buffer, p1, p2); + if (nchars < 0) { + // swap positions if p1 comes after p2 + nchars = -nchars; + BufferPos tmp = p1; + p1 = p2; + p2 = tmp; + } + buffer_delete_chars_at_pos(buffer, p1, nchars); } void buffer_delete_chars_at_cursor(TextBuffer *buffer, i64 nchars) { buffer_delete_chars_at_pos(buffer, buffer->cursor_pos, nchars); } -// returns number of characters backspaced -i64 buffer_backspace(TextBuffer *buffer, i64 ntimes) { - i64 n = buffer_cursor_move_left(buffer, ntimes); - buffer_delete_chars_at_cursor(buffer, n); +i64 buffer_backspace_at_pos(TextBuffer *buffer, BufferPos *pos, i64 ntimes) { + i64 n = buffer_pos_move_left(buffer, pos, ntimes); + buffer_delete_chars_at_pos(buffer, *pos, n); return n; } + +// returns number of characters backspaced +i64 buffer_backspace_at_cursor(TextBuffer *buffer, i64 ntimes) { + return buffer_backspace_at_pos(buffer, &buffer->cursor_pos, ntimes); +} + +void buffer_delete_words_at_pos(TextBuffer *buffer, BufferPos pos, i64 nwords) { + BufferPos pos2 = pos; + buffer_pos_move_right_words(buffer, &pos2, nwords); + buffer_delete_chars_between(buffer, pos, pos2); +} + +void buffer_delete_words_at_cursor(TextBuffer *buffer, i64 nwords) { + buffer_delete_words_at_pos(buffer, buffer->cursor_pos, nwords); +} + +void buffer_backspace_words_at_pos(TextBuffer *buffer, BufferPos *pos, i64 nwords) { + BufferPos pos2 = *pos; + buffer_pos_move_left_words(buffer, pos, nwords); + buffer_delete_chars_between(buffer, pos2, *pos); +} + +void buffer_backspace_words_at_cursor(TextBuffer *buffer, i64 nwords) { + buffer_backspace_words_at_pos(buffer, &buffer->cursor_pos, nwords); +} @@ -130,10 +130,16 @@ int main(void) { buffer_insert_char_at_cursor(&text_buffer, U'\t'); break; case SDLK_DELETE: - buffer_delete_chars_at_cursor(&text_buffer, 1); + if (ctrl) + buffer_delete_words_at_cursor(&text_buffer, 1); + else + buffer_delete_chars_at_cursor(&text_buffer, 1); break; case SDLK_BACKSPACE: - buffer_backspace(&text_buffer, 1); + if (ctrl) + buffer_backspace_words_at_cursor(&text_buffer, 1); + else + buffer_backspace_at_cursor(&text_buffer, 1); break; } } break; |