import { describe, it, expect } from "vitest";
import { buildFingerprint, resolve } from "../src/anchorer";
import { applyChange, type LiveSpan } from "../src/attributionTracker";
import type { Provenance } from "../src/model";

const HUMAN: Provenance = { kind: "human", id: "ben" };
const DOC = "intro\nClaude wrote this sentence here.\noutro\n";

function liveSpan(): LiveSpan {
  const start = DOC.indexOf("Claude wrote this sentence");
  return {
    id: "at_1", start, end: start + "Claude wrote this sentence".length,
    author: { kind: "agent", id: "claude", agent: { sdk: "@cline/sdk", model: "sonnet", sessionId: "r1" } },
    createdAt: "2026-06-10T00:00:00.000Z",
  };
}

describe("attribution persistence decision logic (SLICE-4, spec §6.5 PUC-4)", () => {
  it("save → reload: fingerprint built from the live span resolves to the same range", () => {
    const s = liveSpan();
    const fp = buildFingerprint(DOC, { start: s.start, end: s.end });
    expect(resolve(DOC, fp)).toEqual({ start: s.start, end: s.end });
  });

  it("external edit above: fingerprint re-resolves at the moved range", () => {
    const s = liveSpan();
    const fp = buildFingerprint(DOC, { start: s.start, end: s.end });
    const edited = "a new line\n" + DOC;
    const moved = edited.indexOf("Claude wrote this sentence");
    expect(resolve(edited, fp)).toEqual({ start: moved, end: moved + (s.end - s.start) });
  });

  it("anchored text mangled: orphaned, never guessed (INV-1/INV-6)", () => {
    const s = liveSpan();
    const fp = buildFingerprint(DOC, { start: s.start, end: s.end });
    const mangled = DOC.replace("Claude wrote this sentence", "Someone rewrote everything");
    expect(resolve(mangled, fp)).toBe("orphaned");
  });

  it("in-session edits keep the live span fingerprint-able (tracker → anchorer round trip)", () => {
    let spans = [liveSpan()];
    let doc = DOC;
    const insertAt = DOC.indexOf("intro") + "intro".length;
    const inserted = " (note)";
    doc = doc.slice(0, insertAt) + inserted + doc.slice(insertAt);
    spans = applyChange(spans, { start: insertAt, end: insertAt, newLength: inserted.length }, HUMAN, {
      newId: () => "n1", now: () => "2026-06-10T01:00:00.000Z",
    });
    const agent = spans.find((x) => x.author.kind === "agent")!;
    expect(doc.slice(agent.start, agent.end)).toBe("Claude wrote this sentence");
    const fp = buildFingerprint(doc, { start: agent.start, end: agent.end });
    expect(resolve(doc, fp)).toEqual({ start: agent.start, end: agent.end });
  });
});