asdf

Squash the current repository state back into one baseline commit while
preserving the README reframing and repository contents.

Constraint: User explicitly requested a single squashed commit with subject "asdf"
Confidence: high
Scope-risk: broad
Reversibility: clean
Directive: This commit intentionally rewrites published history; coordinate before future force-pushes
Tested: git status clean; local history rewritten to one commit; force-pushed main to origin and instructkr
Not-tested: Fresh clone verification after push

src/utils/pdfUtils.ts

@@ -0,0 +1,70 @@
+import { getMainLoopModel } from './model/model.js'
+
+// Document extensions that are handled specially
+export const DOCUMENT_EXTENSIONS = new Set(['pdf'])
+
+/**
+ * Parse a page range string into firstPage/lastPage numbers.
+ * Supported formats:
+ * - "5" → { firstPage: 5, lastPage: 5 }
+ * - "1-10" → { firstPage: 1, lastPage: 10 }
+ * - "3-" → { firstPage: 3, lastPage: Infinity }
+ *
+ * Returns null on invalid input (non-numeric, zero, inverted range).
+ * Pages are 1-indexed.
+ */
+export function parsePDFPageRange(
+  pages: string,
+): { firstPage: number; lastPage: number } | null {
+  const trimmed = pages.trim()
+  if (!trimmed) {
+    return null
+  }
+
+  // "N-" open-ended range
+  if (trimmed.endsWith('-')) {
+    const first = parseInt(trimmed.slice(0, -1), 10)
+    if (isNaN(first) || first < 1) {
+      return null
+    }
+    return { firstPage: first, lastPage: Infinity }
+  }
+
+  const dashIndex = trimmed.indexOf('-')
+  if (dashIndex === -1) {
+    // Single page: "5"
+    const page = parseInt(trimmed, 10)
+    if (isNaN(page) || page < 1) {
+      return null
+    }
+    return { firstPage: page, lastPage: page }
+  }
+
+  // Range: "1-10"
+  const first = parseInt(trimmed.slice(0, dashIndex), 10)
+  const last = parseInt(trimmed.slice(dashIndex + 1), 10)
+  if (isNaN(first) || isNaN(last) || first < 1 || last < 1 || last < first) {
+    return null
+  }
+  return { firstPage: first, lastPage: last }
+}
+
+/**
+ * Check if PDF reading is supported with the current model.
+ * PDF document blocks work on all providers (1P, Vertex, Bedrock, Foundry).
+ * Haiku 3 is the only remaining model that predates PDF support; users on
+ * it fall back to the page-extraction path (poppler-utils). Substring match
+ * covers all provider ID formats (Bedrock prefixes, Vertex @-dates).
+ */
+export function isPDFSupported(): boolean {
+  return !getMainLoopModel().toLowerCase().includes('claude-3-haiku')
+}
+
+/**
+ * Check if a file extension is a PDF document.
+ * @param ext File extension (with or without leading dot)
+ */
+export function isPDFExtension(ext: string): boolean {
+  const normalized = ext.startsWith('.') ? ext.slice(1) : ext
+  return DOCUMENT_EXTENSIONS.has(normalized.toLowerCase())
+}