indentlog: refactor: + color_spec, streamline color implementation

This commit is contained in:
Roland Conybeare 2023-09-18 12:25:05 -04:00
commit e324b9d007

View file

@ -13,6 +13,93 @@ namespace xo {
CE_Xterm,
};
/* specify a color (consistent with ANSI escape sequences - the Select Graphics Rendition subset
* see [[https://stackoverflow.com/questions/4842424/list-of-ansi-color-escape-sequences]]
*
* this provides three ways to specify foreground color:
*
* | enum | escape | example | description | foreground codes |
* +-------+-----------+---------------------+---------------+------------------+
* | ansi | \033[31 | \033[31;42m | 4-bit colors | 30..37, 90..97 |
* | xterm | \033[38;5 | \033[38;5;143m | 8-bit colors | 0..255 |
* | rgb | \033[38;2 | \033[38;2;10;20;30m | 24-bit colors | 3x 0..255 |
*
*/
class color_spec {
public:
color_spec() = default;
color_spec(color_encoding encoding, std::uint32_t code)
: encoding_{encoding}, code_{code} {}
static color_spec none() { return color_spec(); }
static color_spec ansi(std::uint32_t code) { return color_spec(CE_Ansi, code); }
static color_spec xterm(std::uint32_t code) { return color_spec(CE_Xterm, code); }
static color_spec rgb(std::uint8_t red, std::uint8_t green, std::uint8_t blue) {
return none();
//return color_spec(CE_Rgb, (red << 16 | green << 8 | blue));
}
/* 4-bit foreground colors */
static color_spec black () { return ansi(30); }
static color_spec red () { return ansi(31); }
static color_spec green () { return ansi(32); }
static color_spec yellow () { return ansi(33); }
static color_spec blue () { return ansi(34); }
static color_spec magenta () { return ansi(35); }
static color_spec cyan () { return ansi(36); }
static color_spec white () { return ansi(37); }
static color_spec bright_black () { return ansi(90); }
static color_spec bright_red () { return ansi(91); }
static color_spec bright_green () { return ansi(92); }
static color_spec bright_yellow () { return ansi(99); }
static color_spec bright_blue () { return ansi(94); }
static color_spec bright_magenta () { return ansi(95); }
static color_spec bright_cyan () { return ansi(96); }
static color_spec bright_white () { return ansi(97); }
color_encoding encoding() const { return encoding_; }
std::uint32_t code() const { return code_; }
void print_fg_color_on (std::ostream & os) const {
switch (encoding_) {
case CE_None:
break;
case CE_Ansi:
os << "\033[31;" << code_ << "m";
break;
case CE_Xterm:
os << "\033[38;5;" << code_ << "m";
break;
}
} /*print_fg_color_on*/
/* escape to reverse effect of .print_on() */
void print_fg_color_off (std::ostream & os) const {
switch (encoding_) {
case CE_None:
break;
case CE_Ansi:
case CE_Xterm:
os << "\033[0m";
break;
}
} /*print_fg_color_off*/
private:
/* none | ansi | xterm | rgb */
color_encoding encoding_ = CE_None;
/* ansi : 30..37, 90..97
* xterm : 0..255
* see [[https://i.stack.imgur.com/KTSQa.png]]
* 0..7 standard colors (muted: grey, red, green, yellow, blue, pink, cyan, white)
* 8..15 high-intensity colors (grey, red, green, yellow, blue, pink, cyan, white)
* 16..51 chooses hue
* 16..51 + (0..5)x36 increases whiteness
* rgb : r={hi 8 bits}, g={mid 8 bits}, b={lo 8 bits}
*/
std::uint32_t code_ = 0;
}; /*color_spec*/
enum color_flags {
CF_None = 0x0,
CF_ColorOn = 0x01,
@ -21,66 +108,31 @@ namespace xo {
CF_All = 0x07
};
/* stream-insertable color control */
template <typename Contents>
class color_impl {
public:
color_impl(color_flags flags, color_encoding encoding, std::uint32_t color, Contents && contents)
: flags_{flags}, encoding_{encoding}, color_{color}, contents_{std::forward<Contents>(contents)} {}
: flags_{flags}, spec_(encoding, color), contents_{std::forward<Contents>(contents)} {}
std::uint32_t color() const { return color_; }
std::uint32_t color() const { return spec_.code(); }
Contents const & contents() const { return contents_; }
void print(std::ostream & os) const {
if ((flags_ & CF_ColorOn) && (color_ > 0)) {
switch(encoding_) {
case CE_None:
break;
case CE_Ansi:
os << "\033[" << color_ << "m";
break;
case CE_Xterm:
os << "\033[38;5;" << color_ << "m";
break;
}
}
if (flags_ & CF_ColorOn)
spec_.print_fg_color_on(os);
if (flags_ & CF_Contents)
os << contents_;
if ((flags_ & CF_ColorOff) && (color_ > 0)) {
switch(encoding_) {
case CE_None:
break;
case CE_Ansi:
case CE_Xterm:
os << "\033[0m";
break;
}
}
if (flags_ & CF_ColorOff)
spec_.print_fg_color_off(os);
} /*print*/
private:
color_flags flags_ = CF_None;
color_encoding encoding_ = CE_Ansi;
/* .encoding = CE_Ansi:
* 0 = no color
* 30 = black
* 31 = red
* 32 = green
* 33 = yellow
* 34 = blue
* 35 = magenta
* 36 = cyan
*
* .encoding = CE_Xterm:
* see [[https://i.stack.imgur.com/KTSQa.png]]
* 0..7 standard colors (muted: grey, red, green, yellow, blue, pink, cyan, white)
* 8..15 high-intensity colors (grey, red, green, yellow, blue, pink, cyan, white)
* 16..51 chooses hue
* 16..51 + (0..5)x36 increases whiteness
*/
std::uint32_t color_ = 0;
color_spec spec_;
Contents contents_;
}; /*color_impl*/