[Init] Initial commit - NetMesh terminal manager

domain/terminalContextRead.ts

@@ -0,0 +1,214 @@
+export type TerminalContextReadRange = "viewport" | "tail" | "head" | "lines";
+
+export type TerminalContextReadSource = "live" | "snapshot";
+
+export const TERMINAL_CONTEXT_DEFAULT_MAX_LINES = 80;
+export const TERMINAL_CONTEXT_MAX_LINES = 300;
+
+export interface TerminalContextReadRequest {
+  sessionId?: string;
+  range?: TerminalContextReadRange;
+  startLine?: number;
+  maxLines?: number;
+}
+
+export interface TerminalContextLineWindowInput {
+  range?: TerminalContextReadRange;
+  totalLines: number;
+  viewportStartLine?: number;
+  viewportEndLine?: number;
+  startLine?: number;
+  maxLines?: number;
+}
+
+export interface TerminalContextLineWindow {
+  startLine: number;
+  endLine: number;
+  maxLines: number;
+}
+
+export interface TerminalContextReadResult {
+  ok: true;
+  sessionId: string;
+  label?: string;
+  range: TerminalContextReadRange;
+  content: string;
+  totalLines: number;
+  startLine: number;
+  endLine: number;
+  returnedLines: number;
+  hasMoreBefore: boolean;
+  hasMoreAfter: boolean;
+  source: TerminalContextReadSource;
+  alternateScreen?: boolean;
+}
+
+export type TerminalContextReader = (
+  request: TerminalContextReadRequest & { sessionId: string },
+) => Promise<TerminalContextReadResult | { ok: false; error: string }>;
+
+export interface BuildTerminalContextReadResultInput {
+  sessionId: string;
+  label?: string;
+  fullText: string;
+  range?: TerminalContextReadRange;
+  startLine?: number;
+  maxLines?: number;
+  source: TerminalContextReadSource;
+  alternateScreen?: boolean;
+  viewportStartLine?: number;
+  viewportEndLine?: number;
+}
+
+export interface TerminalContextSnapshotTextInput {
+  scrollbackText?: string;
+  viewportText?: string;
+  pendingText?: string;
+}
+
+export interface TerminalContextSnapshotText {
+  fullText: string;
+  viewportStartLine?: number;
+  viewportEndLine?: number;
+}
+
+export function normalizeTerminalContextMaxLines(value: unknown): number {
+  if (typeof value !== "number" || !Number.isFinite(value)) {
+    return TERMINAL_CONTEXT_DEFAULT_MAX_LINES;
+  }
+  return Math.min(
+    TERMINAL_CONTEXT_MAX_LINES,
+    Math.max(1, Math.round(value)),
+  );
+}
+
+export function normalizeTerminalContextRange(value: unknown): TerminalContextReadRange {
+  if (
+    value === "viewport" ||
+    value === "tail" ||
+    value === "head" ||
+    value === "lines"
+  ) {
+    return value;
+  }
+  return "viewport";
+}
+
+export function resolveTerminalContextLineWindow(
+  input: TerminalContextLineWindowInput,
+): TerminalContextLineWindow {
+  const range = normalizeTerminalContextRange(input.range);
+  const maxLines = normalizeTerminalContextMaxLines(input.maxLines);
+  const totalLines = Math.max(0, Math.floor(input.totalLines));
+
+  if (totalLines === 0) {
+    return { startLine: 0, endLine: -1, maxLines };
+  }
+
+  if (range === "head") {
+    return {
+      startLine: 0,
+      endLine: Math.min(totalLines - 1, maxLines - 1),
+      maxLines,
+    };
+  }
+
+  if (range === "tail") {
+    return {
+      startLine: Math.max(0, totalLines - maxLines),
+      endLine: totalLines - 1,
+      maxLines,
+    };
+  }
+
+  if (range === "lines") {
+    const start = clampLine(input.startLine, totalLines);
+    return {
+      startLine: start,
+      endLine: Math.min(totalLines - 1, start + maxLines - 1),
+      maxLines,
+    };
+  }
+
+  const viewportStart = clampLine(input.viewportStartLine, totalLines);
+  const viewportEnd = clampLine(input.viewportEndLine, totalLines);
+  const rawStart = Math.min(viewportStart, viewportEnd);
+  const end = Math.max(viewportStart, viewportEnd);
+  const start = Math.max(rawStart, end - maxLines + 1);
+  return { startLine: start, endLine: end, maxLines };
+}
+
+export function buildTerminalContextReadResult(
+  input: BuildTerminalContextReadResultInput,
+): TerminalContextReadResult {
+  const range = normalizeTerminalContextRange(input.range);
+  const lines = splitTerminalContextLines(input.fullText);
+  const totalLines = lines.length;
+  const window = resolveTerminalContextLineWindow({
+    range,
+    totalLines,
+    viewportStartLine: input.viewportStartLine,
+    viewportEndLine: input.viewportEndLine,
+    startLine: input.startLine,
+    maxLines: input.maxLines,
+  });
+  const selectedLines = window.endLine >= window.startLine
+    ? lines.slice(window.startLine, window.endLine + 1)
+    : [];
+
+  return {
+    ok: true,
+    sessionId: input.sessionId,
+    label: input.label,
+    range,
+    content: selectedLines.join("\n"),
+    totalLines,
+    startLine: window.startLine,
+    endLine: window.endLine,
+    returnedLines: selectedLines.length,
+    hasMoreBefore: window.startLine > 0,
+    hasMoreAfter: window.endLine >= 0 && window.endLine < totalLines - 1,
+    source: input.source,
+    alternateScreen: input.alternateScreen,
+  };
+}
+
+export function buildTerminalContextSnapshotText(
+  input: TerminalContextSnapshotTextInput,
+): TerminalContextSnapshotText {
+  const parts: Array<{ kind: "scrollback" | "viewport" | "pending"; text: string }> = [];
+  if (input.scrollbackText) parts.push({ kind: "scrollback", text: input.scrollbackText });
+  if (input.viewportText) parts.push({ kind: "viewport", text: input.viewportText });
+  if (input.pendingText) parts.push({ kind: "pending", text: input.pendingText });
+
+  let lineOffset = 0;
+  let viewportStartLine: number | undefined;
+  let viewportEndLine: number | undefined;
+  for (const part of parts) {
+    const lineCount = splitTerminalContextLines(part.text).length;
+    if (part.kind === "viewport") {
+      viewportStartLine = lineOffset;
+      viewportEndLine = lineOffset + lineCount - 1;
+    } else if (part.kind === "pending" && viewportStartLine !== undefined) {
+      viewportEndLine = lineOffset + lineCount - 1;
+    }
+    lineOffset += lineCount;
+  }
+
+  return {
+    fullText: parts.map((part) => part.text).join("\n"),
+    viewportStartLine,
+    viewportEndLine,
+  };
+}
+
+function splitTerminalContextLines(text: string): string[] {
+  if (!text) return [];
+  return text.replace(/\r\n/g, "\n").replace(/\r/g, "\n").split("\n");
+}
+
+function clampLine(value: unknown, totalLines: number): number {
+  if (totalLines <= 0) return 0;
+  if (typeof value !== "number" || !Number.isFinite(value)) return 0;
+  return Math.min(totalLines - 1, Math.max(0, Math.floor(value)));
+}