/**
* Matrix Rain Intro — green digital rain before chat starts
*/
import chalk from "chalk";
const CHARS = "ﾊﾐﾋｰｳｼﾅﾓﾆｻﾜﾂｵﾘｱﾎﾃﾏｹﾒｴｶｷﾑﾕﾗｾﾈｽﾀﾇﾍ0123456789ABCDEFZ";
const green0 = chalk.hex("#003B00");
const green1 = chalk.hex("#008F11");
const green2 = chalk.hex("#00FF41");
const white = chalk.hex("#FFFFFF");
const brand = chalk.hex("#00FF41").bold;
interface Drop {
y: number;
speed: number;
trail: number;
}
function randChar(): string {
return CHARS[Math.floor(Math.random() * CHARS.length)];
}
export async function matrixIntro(durationMs = 2200): Promise<void> {
return new Promise((resolve) => {
const cols = process.stdout.columns || 80;
const rows = Math.min((process.stdout.rows || 24) - 1, 24);
const drops: Drop[] = Array.from({ length: cols }, () => ({
y: Math.random() * -rows * 1.5,
speed: 0.3 + Math.random() * 0.7,
trail: 4 + Math.floor(Math.random() * 10),
}));
// Hide cursor, clear screen
process.stdout.write("\x1b[?25l\x1b[2J\x1b[H");
const start = Date.now();
const fadeStart = durationMs * 0.65;
const tick = setInterval(() => {
const elapsed = Date.now() - start;
const fading = elapsed > fadeStart;
let output = "\x1b[H";
for (const d of drops) {
d.y += d.speed;
if (d.y - d.trail > rows + 5) {
if (fading) {
d.y = -999;
} else {
d.y = Math.random() * -8;
d.speed = 0.3 + Math.random() * 0.7;
d.trail = 4 + Math.floor(Math.random() * 10);
}
}
}
for (let r = 0; r < rows; r++) {
let line = "";
for (let c = 0; c < cols; c++) {
const d = drops[c];
const dist = Math.floor(d.y) - r;
if (dist < 0 || dist > d.trail) {
line += " ";
} else {
const ch = randChar();
if (dist === 0) line += white(ch);
else if (dist < d.trail * 0.3) line += green2(ch);
else if (dist < d.trail * 0.6) line += green1(ch);
else line += green0(ch);
}
}
output += line + (r < rows - 1 ? "\n" : "");
}
process.stdout.write(output);
if (elapsed >= durationMs) {
clearInterval(tick);
// Flash brand in center
process.stdout.write("\x1b[2J\x1b[H");
const label = "◆ whale code";
const brandRow = Math.floor(rows / 2);
const brandCol = Math.max(1, Math.floor((cols - label.length) / 2));
process.stdout.write(`\x1b[${brandRow};${brandCol}H`);
process.stdout.write(brand(label));
setTimeout(() => {
process.stdout.write("\x1b[2J\x1b[H\x1b[?25h");
resolve();
}, 700);
}
}, 50);
});
}
