ke/scratch.c

/*
 * scratch.c - ideas in progress
 */

#define REFLOW_MARGIN		72

void
reflow_region(void)
{
	int		 start_row, end_row, i, col, wlen, this_len;
	struct erow	*row;
	struct abuf	 buf = ABUF_INIT;
	struct abuf	 out = ABUF_INIT;
	int		 in_paragraph = 0;
	int		 indent_len = 0;
	char		 indent[REFLOW_MARGIN + 1];
	char		 word[REFLOW_MARGIN + 1];
	char		*e = NULL;
	char		*p = NULL;
	char		*s = NULL;

	if (editor.mark_set) {
		if (editor.mark_cury < editor.cury ||
			(editor.mark_cury == editor.cury &&
				editor.mark_curx < editor.curx)) {
			start_row = editor.mark_cury;
			end_row = editor.cury;
		} else {
			start_row = editor.cury;
			end_row = editor.mark_cury;
		}
	} else {
		start_row = end_row = editor.cury;
		while (start_row > 0 && editor.row[start_row - 1].size > 0) {
			start_row--;
		}

		while (end_row < editor.nrows - 1 &&
			editor.row[end_row + 1].size > 0) {
			end_row++;
		}
	}

	if (start_row >= editor.nrows) {
		return;
	}

	if (end_row >= editor.nrows) {
		end_row = editor.nrows - 1;
	}

	for (i = start_row; i <= end_row; i++) {
		row = &editor.row[i];

		if (row->size == 0) {
			if (in_paragraph) {
				ab_append(&buf, "\n", 1);
				in_paragraph = 0;
			}

			ab_append(&buf, "\n", 1);
			continue;
		}

		if (!in_paragraph) {
			indent_len = 0;
			while (indent_len < row->size &&
				(row->line[indent_len] == ' ' ||
					row->line[indent_len] == '\t')) {
				indent[indent_len] = row->line[indent_len], indent_len++;
			}

			indent[indent_len] = '\0';
			in_paragraph = 1;
		}

		ab_append(&buf, row->line + indent_len, row->size - indent_len);
		ab_append(&buf, " ", 1);
	}

	if (in_paragraph) {
		ab_append(&buf, "\n", 1);
	}


	p = buf.b;
	col = 0;

	while (p != NULL && *p != '\0') {
		while (*p && isspace((unsigned char)*p) &&
			*p != '\n') {
			p++;
		}

		if (*p == '\0') {
			break;
		}

		wlen = 0;
		while (*p && !isspace((unsigned char)*p)) {
			if (wlen < REFLOW_MARGIN)
				word[wlen++] = *p;
			p++;
		}
		word[wlen] = '\0';

		if (*p == '\n' && (p[1] == '\n' || p[1] == '\0')) {
			ab_append(&out, "\n", 1); /* flush */
			col = 0;
			p++; /* consume the extra \n */
			continue;
		}

		this_len = wlen;
		if (col > 0) {
			this_len++; /* space before word */
		}

		if (col == 0) {
			ab_append(&out, indent, indent_len);
			col = indent_len;
		}

		if (col + this_len > REFLOW_MARGIN && col > 0) {
			ab_append(&out, "\n", 1);
			ab_append(&out, indent, indent_len);
			col = indent_len;
		}

		if (col > 0) {
			ab_append(&out, " ", 1);
			col++;
		}

		ab_append(&out, word, wlen);
		col += wlen;
	}

	if (col > 0) {
		ab_append(&out, "\n", 1);
	}

	/* the old switcharoo */
	buf = out;
	ab_free(&out);


	for (i = end_row; i >= start_row; i--) {
		delete_row(i);
	}

	s = buf.b;
	while ((e = strchr(s, '\n'))) {
		erow_insert(start_row++, s, e - s);
		s = e + 1;
	}

	ab_free(&buf);

	editor.dirty++;
	editor_set_status("Region reflowed to %d columns", REFLOW_MARGIN);
}