Initial commit

Signed-off-by: Ilan Bigio <ilan@openai.com>

codex-cli/src/components/chat/terminal-chat-utils.ts

@@ -0,0 +1,113 @@
+import type { ResponseItem } from "openai/resources/responses/responses.mjs";
+
+import { approximateTokensUsed } from "../../utils/approximate-tokens-used.js";
+
+/**
+ * Type‑guard that narrows a {@link ResponseItem} to one that represents a
+ * user‑authored message. The OpenAI SDK represents both input *and* output
+ * messages with a discriminated union where:
+ *   • `type` is the string literal "message" and
+ *   • `role` is one of "user" | "assistant" | "system" | "developer".
+ *
+ * For the purposes of de‑duplication we only care about *user* messages so we
+ * detect those here in a single, reusable helper.
+ */
+function isUserMessage(
+  item: ResponseItem,
+): item is ResponseItem & { type: "message"; role: "user"; content: unknown } {
+  return item.type === "message" && (item as { role?: string }).role === "user";
+}
+
+/**
+ * Returns the maximum context length (in tokens) for a given model.
+ * These numbers are best‑effort guesses and provide a basis for UI percentages.
+ */
+export function maxTokensForModel(model: string): number {
+  const lower = model.toLowerCase();
+  if (lower.includes("32k")) {
+    return 32000;
+  }
+  if (lower.includes("16k")) {
+    return 16000;
+  }
+  if (lower.includes("8k")) {
+    return 8000;
+  }
+  if (lower.includes("4k")) {
+    return 4000;
+  }
+  // Default to 128k for newer long‑context models
+  return 128000;
+}
+
+/**
+ * Calculates the percentage of tokens remaining in context for a model.
+ */
+export function calculateContextPercentRemaining(
+  items: Array<ResponseItem>,
+  model: string,
+): number {
+  const used = approximateTokensUsed(items);
+  const max = maxTokensForModel(model);
+  const remaining = Math.max(0, max - used);
+  return (remaining / max) * 100;
+}
+
+/**
+ * Deduplicate the stream of {@link ResponseItem}s before they are persisted in
+ * component state.
+ *
+ * Historically we used the (optional) {@code id} field returned by the
+ * OpenAI streaming API as the primary key: the first occurrence of any given
+ * {@code id} “won” and subsequent duplicates were dropped.  In practice this
+ * proved brittle because locally‑generated user messages don’t include an
+ * {@code id}.  The result was that if a user quickly pressed <Enter> twice the
+ * exact same message would appear twice in the transcript.
+ *
+ * The new rules are therefore:
+ *   1.  If a {@link ResponseItem} has an {@code id} keep only the *first*
+ *       occurrence of that {@code id} (this retains the previous behaviour for
+ *       assistant / tool messages).
+ *   2.  Additionally, collapse *consecutive* user messages with identical
+ *       content.  Two messages are considered identical when their serialized
+ *       {@code content} array matches exactly.  We purposefully restrict this
+ *       to **adjacent** duplicates so that legitimately repeated questions at
+ *       a later point in the conversation are still shown.
+ */
+export function uniqueById(items: Array<ResponseItem>): Array<ResponseItem> {
+  const seenIds = new Set<string>();
+  const deduped: Array<ResponseItem> = [];
+
+  for (const item of items) {
+    // ──────────────────────────────────────────────────────────────────
+    // Rule #1 – de‑duplicate by id when present
+    // ──────────────────────────────────────────────────────────────────
+    if (typeof item.id === "string" && item.id.length > 0) {
+      if (seenIds.has(item.id)) {
+        continue; // skip duplicates
+      }
+      seenIds.add(item.id);
+    }
+
+    // ──────────────────────────────────────────────────────────────────
+    // Rule #2 – collapse consecutive identical user messages
+    // ──────────────────────────────────────────────────────────────────
+    if (isUserMessage(item) && deduped.length > 0) {
+      const prev = deduped[deduped.length - 1]!;
+
+      if (
+        isUserMessage(prev) &&
+        // Note: the `content` field is an array of message parts. Performing
+        // a deep compare is over‑kill here; serialising to JSON is sufficient
+        // (and fast for the tiny payloads involved).
+        JSON.stringify(prev.content) === JSON.stringify(item.content)
+      ) {
+        continue; // skip duplicate user message
+      }
+    }
+
+    deduped.push(item);
+  }
+
+  return deduped;
+}