import * as assert from "assert";
import * as fs from "fs";
import * as path from "path";
import * as vscode from "vscode";
import type { CowritingApi } from "../../../src/extension";

const WS = process.env.E2E_WORKSPACE!;
const settle = () => new Promise((r) => setTimeout(r, 400));

async function getApi(): Promise<CowritingApi> {
  const ext = vscode.extensions.getExtension("benstull.vscode-cowriting-plugin")!;
  const api = (await ext.activate()) as CowritingApi;
  assert.ok(api?.trackChangesPreviewController, "exports preview controller");
  return api;
}

async function freshDoc(rel: string, body: string): Promise<{ doc: vscode.TextDocument; key: string }> {
  const abs = path.join(WS, rel);
  fs.mkdirSync(path.dirname(abs), { recursive: true });
  fs.writeFileSync(abs, body, "utf8");
  const uri = vscode.Uri.file(abs);
  const doc = await vscode.workspace.openTextDocument(uri);
  // INV-10: cowriting.editDocument now warns instead of editing a non-entered
  // doc (Task 4) — enter it here (briefly making it active) so the tests below
  // exercise the routing/targeting behavior, not the gate. The caller
  // re-establishes whichever doc it wants active afterward.
  await vscode.window.showTextDocument(doc);
  await vscode.commands.executeCommand("cowriting.coeditDocument");
  return { doc, key: uri.toString() };
}

function pkg(): any {
  return JSON.parse(fs.readFileSync(path.join(__dirname, "../../../../package.json"), "utf8"));
}
function menu(id: string): Array<{ command: string; when?: string; group?: string }> {
  return pkg().contributes.menus[id] ?? [];
}

// SLICE-1 / #42 (reach): "Ask Claude to Edit" reachable from the editor BODY and
// the editor TAB. The two split commands (editSelection / editDocument) were
// unified behind ONE user-facing command `cowriting.edit` that auto-routes by
// selection at runtime (routeEdit: selection → editSelection, none → editDocument)
// — so the menus carry a SINGLE selection-agnostic entry, both markdown/authorable
// -gated. The routing itself is unit-tested (routeEdit) and exercised through the
// command below; here we assert the declarative menu `when` clauses.
suite("F12 SLICE-1 — Ask-Claude reach (#42, INV-38)", () => {
  // PUC-1/2: editor BODY (editor/context) offers the single unified entry,
  // markdown + authorable gated, NOT selection-gated (it routes both cases).
  test("editor/context offers a single 'Ask Claude to Edit' (cowriting.edit), markdown+authorable", () => {
    const m = menu("editor/context");
    const edit = m.find((e) => e.command === "cowriting.edit");
    assert.ok(edit, "cowriting.edit is in editor/context");
    assert.match(edit!.when ?? "", /editorLangId == markdown/, "gated on markdown");
    assert.match(edit!.when ?? "", /resourceScheme == file|resourceScheme == untitled/, "gated authorable");
    assert.ok(!/editorHasSelection/.test(edit!.when ?? ""), "not selection-gated — one entry routes both cases");
    // The old split pair is gone from the menu (the commands stay registered/hidden).
    assert.ok(!m.some((e) => e.command === "cowriting.editSelection"), "old editSelection menu entry removed");
    assert.ok(!m.some((e) => e.command === "cowriting.editDocument"), "old editDocument menu entry removed");
  });

  // PUC-3: editor TAB (editor/title/context) carries the same single entry.
  test("editor/title/context offers a single 'Ask Claude to Edit' (cowriting.edit), markdown-gated", () => {
    const m = menu("editor/title/context");
    const edit = m.find((e) => e.command === "cowriting.edit");
    assert.ok(edit, "cowriting.edit is in editor/title/context");
    assert.match(edit!.when ?? "", /resourceLangId == markdown/, "tab entry gated on markdown");
    assert.ok(
      !m.some((e) => e.command === "cowriting.editSelection" || e.command === "cowriting.editDocument"),
      "old split pair removed from the tab menu",
    );
  });

  // PUC-3 behavior: editDocument invoked with a tab URI targets THAT document,
  // not whatever editor happens to be active (mirrors #41's clicked-doc resolution).
  test("editDocument(uri) targets the clicked tab's document, not the active editor", async () => {
    const api = await getApi();
    const editFlow = api.editFlow;

    // Doc A is the active editor; Doc B is the "clicked tab" we pass by URI.
    const a = await freshDoc("docs/f12-active.md", "# Active\n\nThe active editor paragraph.\n");
    const b = await freshDoc("docs/f12-tab.md", "# Tab\n\nThe tab target paragraph to rewrite.\n");
    await vscode.window.showTextDocument(a.doc);
    await settle();

    // Stub the document instruction prompt (the webview can't run in CI) + the LLM turn.
    const origPrompt = editFlow.askEditInstruction;
    editFlow.askEditInstruction = async () => "rewrite it";
    editFlow.setEditTurnForTest(async () => ({
      replacement: "# Tab\n\nThe REWRITTEN tab paragraph.\n",
      model: "sonnet",
      sessionId: "e2e-f12-tab",
    }));
    try {
      await vscode.commands.executeCommand("cowriting.editDocument", b.doc.uri);
      await settle();
    } finally {
      editFlow.askEditInstruction = origPrompt;
    }

    // The proposal(s) landed on the TAB doc (B), and the ACTIVE doc (A) has none.
    assert.ok(api.proposalController.listProposals(b.doc).length >= 1, "tab doc B received the document-edit proposal(s)");
    assert.strictEqual(
      api.proposalController.listProposals(a.doc).length,
      0,
      "active doc A was NOT edited — editDocument honored the tab URI",
    );
    // F12 (INV-48): EditorProposalController optimistically applies proposals into the
    // buffer, so the proposed text is now in the tab doc B. Confirm one of the proposal
    // texts is present (the tab doc was edited, not A).
    assert.ok(b.doc.getText().includes("REWRITTEN"), "F12 optimistic-apply: proposed text in tab doc B");
  });

  // No URI arg (palette / keybinding) → fall back to the active editor.
  test("editDocument() with no arg targets the active editor", async () => {
    const api = await getApi();
    const editFlow = api.editFlow;
    const a = await freshDoc("docs/f12-noarg.md", "# No arg\n\nThe active doc paragraph here.\n");
    await vscode.window.showTextDocument(a.doc);
    await settle();

    const origPrompt = editFlow.askEditInstruction;
    editFlow.askEditInstruction = async () => "rewrite it";
    editFlow.setEditTurnForTest(async () => ({
      replacement: "# No arg\n\nThe REWRITTEN active doc paragraph.\n",
      model: "sonnet",
      sessionId: "e2e-f12-noarg",
    }));
    try {
      await vscode.commands.executeCommand("cowriting.editDocument");
      await settle();
    } finally {
      editFlow.askEditInstruction = origPrompt;
    }
    assert.ok(api.proposalController.listProposals(a.doc).length >= 1, "active doc received the proposal(s) on no-arg");
  });
});