/**
* 计算字符串的显示宽度
* @param str UTF-8编码字符串
* @param size 字符串的长度
* @return 字符串在编辑器终端上的显示宽度
*/
static size_t display_width(const char *str, size_t size)
{
size_t width = 0;
for (wchar_t wc = next_wchar(&str, &size); wc && wc != WEOF; ) {
width += display_width_wchar(wc);
wc = next_wchar(&str, &size);
}
return width;
}
static const char *seek_to_display_width(const char *str, size_t size,
size_t width)
{
const char *last = str;
for (wchar_t wc = next_wchar(&str, &size); wc && wc != WEOF; ) {
size_t w = display_width_wchar(wc);
if (w > width) {
return last;
} else {
last = str;
width -= w;
}
wc = next_wchar(&str, &size);
}
return last;
}
static const char *update_quote_width(const char *begin, const char *end,
bool utf8, size_t *width)
{
const char *ptr = begin;
while (ptr < end && *width) {
if (utf8) {
size_t left = end - ptr;
const char *next = ptr;
wchar_t wc = next_wchar(&next, &left);
if (!wc || wc == WEOF)
return ptr;
int w = fb_wcwidth(wc);
if (w <= 0)
w = next - ptr > 0 ? next - ptr : 1;
if (*width < w)
return ptr;
*width -= w;
ptr = next;
} else {
if (*ptr & 0x80) {
if (*width < 2)
return ptr;
*width -= 2;
ptr += 2;
} else {
*width -= 1;
++ptr;
}
}
}
return ptr > end ? end : ptr;
}
size_t screen_display_width(const char *ptr, bool utf8)
{
size_t width = 0;
bool ansi = false;
while (*ptr) {
if (ansi) {
if (isalpha(*ptr))
ansi = false;
} else {
if (*ptr == '\033') {
ansi = true;
} else {
if (utf8) {
wchar_t wc = next_wchar(&ptr, NULL);
if (wc == WEOF)
break;
width += fb_wcwidth(wc);
--ptr;
} else {
++width;
}
}
}
++ptr;
}
return width;
}
/**
* Find newline in [begin, end), truncate at TRUNCATE_WIDTH.
* @param begin The head pointer.
* @param end The off-the-end pointer.
* @param utf8 是否以UTF-8编码
* @return Off-the-end pointer to the first (truncated) line.
*/
static const char *get_truncated_line(const char *begin, const char *end,
bool utf8)
{
const char *code = "[0123456789;";
bool ansi = false;
int width = TRUNCATE_WIDTH;
if (end - begin >= 2 && *begin == ':' && *(begin + 1) == ' ')
width += 2;
for (const char *s = begin; s < end; ++s) {
if (*s == '\n')
return s + 1;
if (*s == '\033') {
ansi = true;
continue;
}
if (ansi) {
if (!memchr(code, *s, sizeof(code) - 1))
ansi = false;
continue;
}
if (*s & 0x80) {
if (utf8) {
const char *ptr = s;
size_t size = end - s;
wchar_t wc = next_wchar(&ptr, &size);
if (wc == WEOF || wc == 0) {
++s;
} else {
width -= fb_wcwidth(wc);
if (width < 0)
return s;
s = ptr - 1;
}
} else {
width -= 2;
if (width < 0)
return s;
++s;
}
if (width == 0)
return (s + 1 > end ? end : s + 1);
} else {
if (--width == 0)
return s + 1;
}
}
return end;
}
static wchar_t get_next_wchar(editor_t *editor)
{
const char *buffer = NULL;
size_t bytes = 0;
char utf8_buffer[8] = { '\0' };
int ch = terminal_getchar();
editor->input_buffer[(int) editor->pending_bytes++] = ch;
if (terminal_is_utf8()) {
buffer = editor->input_buffer;
bytes = editor->pending_bytes;
} else {
if (editor->pending_bytes > 1) {
convert(CONVERT_G2U, editor->input_buffer, editor->pending_bytes,
utf8_buffer, sizeof(utf8_buffer), NULL, NULL);
editor->pending_bytes = 0;
if (utf8_buffer[0] != '\0') {
buffer = utf8_buffer;
bytes = strlen(utf8_buffer);
}
} else if (!(ch & 0x80)) {
editor->pending_bytes = 0;
return ch;
}
}
if (buffer) {
wchar_t wc = next_wchar(&buffer, &bytes);
if ((wc && wc != WEOF)
|| editor->pending_bytes == sizeof(editor->input_buffer)) {
editor->pending_bytes = 0;
return wc;
}
}
return 0;
}
