[Init] Initial commit - NetMesh terminal manager

components/terminal/terminalContextBuffer.ts

@@ -0,0 +1,42 @@
+import type { IBuffer, Terminal as XTerm } from "@xterm/xterm";
+
+export type TerminalTextRange = {
+  startLine: number;
+  endLine: number;
+};
+
+type TerminalBufferTextSource = Pick<XTerm, "buffer" | "cols">;
+
+export function readActiveTerminalBufferTextRange(
+  term: TerminalBufferTextSource,
+  range: TerminalTextRange,
+): string {
+  const startLine = Math.max(0, Math.floor(range.startLine));
+  const endLine = Math.max(-1, Math.floor(range.endLine));
+  if (endLine < startLine) return "";
+
+  return readTerminalBufferTextRange(term.buffer.active, {
+    ...range,
+    cols: term.cols,
+  });
+}
+
+export function readTerminalBufferTextRange(
+  buffer: Pick<IBuffer, "getLine">,
+  range: TerminalTextRange & { cols?: number },
+): string {
+  const startLine = Math.max(0, Math.floor(range.startLine));
+  const endLine = Math.max(-1, Math.floor(range.endLine));
+  if (endLine < startLine) return "";
+
+  const cols = typeof range.cols === "number" && Number.isFinite(range.cols)
+    ? Math.max(0, Math.floor(range.cols))
+    : undefined;
+
+  const lines: string[] = [];
+  for (let lineIndex = startLine; lineIndex <= endLine; lineIndex += 1) {
+    const line = buffer.getLine(lineIndex);
+    lines.push(line?.translateToString(true, 0, cols) ?? "");
+  }
+  return lines.join("\n");
+}