textui/ansi.ts

91 lines
2.2 KiB
TypeScript

import { BufferLocation, BufferSize, Char, Color } from "./base.ts";
import { Display } from "./display.ts";
/**
* ANSI terminal display
*/
export class AnsiTerminalDisplay implements Display {
private palette_bg: readonly Uint8Array[] = [];
private palette_fg: readonly Uint8Array[] = [];
private width = 1;
private state = { x: -1, y: -1, f: -1, b: -1 }; // current location and color
constructor(
private writer: Deno.Writer = Deno.stdout,
private reader: Deno.Reader = Deno.stdin,
) {
}
async getSize(): Promise<BufferSize> {
const size = Deno.consoleSize(Deno.stdout.rid);
this.width = size.columns;
return {
w: size.columns,
h: size.rows,
};
}
async setupPalette(colors: readonly Color[]): Promise<readonly Color[]> {
// TODO handle not fully rgb compatible terminals
const cr = (x: number) => Math.round(x * 255);
this.palette_bg = colors.map((col) =>
escape(`[48;2;${cr(col.r)};${cr(col.g)};${cr(col.b)}m`)
);
this.palette_fg = colors.map((col) =>
escape(`[38;2;${cr(col.r)};${cr(col.g)};${cr(col.b)}m`)
);
return colors;
}
async clear(): Promise<void> {
await this.writer.write(CLEAR);
}
async setChar(at: BufferLocation, char: Char): Promise<void> {
let { x, y, f, b } = this.state;
if (f != char.fg) {
f = char.fg;
const col = this.palette_fg[f];
if (col) {
await this.writer.write(col);
}
}
if (b != char.bg) {
b = char.bg;
const col = this.palette_bg[b];
if (col) {
await this.writer.write(col);
}
}
if (x != at.x || y != at.y) {
x = at.x;
y = at.y;
await this.writer.write(escape(`[${y + 1};${x + 1}H`));
}
await this.writer.write(new TextEncoder().encode(char.ch));
x += 1;
if (x >= this.width) {
x = 0;
y += 1;
}
this.state = { x, y, f, b };
}
/**
* Force the display size for subsequent prints
*/
forceSize(size: BufferSize) {
this.width = size.w;
}
}
function escape(sequence: string): Uint8Array {
return new Uint8Array([0x1B, ...new TextEncoder().encode(sequence)]);
}
const CLEAR = escape("[2J");