import { describe, expect, it } from "vitest";
import type { WorkspaceCommandState } from "./workspaceCommands";
import {
  cloneCommandState,
  createSnapshotCommand,
  reviveWorkspaceCommand,
  toWorkspaceCommandRecord,
} from "./workspaceCommands";

function makeState(pageIds: string[]): WorkspaceCommandState {
  return {
    pages: pageIds.map((id, index) => ({
      id,
      sourcePageIndex: index,
      rotation: index * 90,
    })),
    selectedPageIds: pageIds.slice(0, 1),
    lastSelectedVisualIndex: pageIds.length > 0 ? 0 : null,
  };
}

describe("workspaceCommands", () => {
  it("clones command state deeply enough for page and selection changes", () => {
    const original = makeState(["a", "b"]);
    const cloned = cloneCommandState(original);

    original.pages[0].rotation = 270;
    original.selectedPageIds.push("b");
    original.lastSelectedVisualIndex = 1;

    expect(cloned).toEqual({
      pages: [
        { id: "a", sourcePageIndex: 0, rotation: 0 },
        { id: "b", sourcePageIndex: 1, rotation: 90 },
      ],
      selectedPageIds: ["a"],
      lastSelectedVisualIndex: 0,
    });
  });

  it("creates snapshot commands that are stable after source states mutate", () => {
    const before = makeState(["a", "b"]);
    const after = makeState(["b", "a"]);
    after.selectedPageIds = ["b"];
    after.lastSelectedVisualIndex = 0;

    const command = createSnapshotCommand({
      id: "cmd-1",
      type: "reorder-pages",
      label: "Move page",
      timestamp: "2026-05-17T10:00:00.000Z",
      before,
      after,
      details: { moved: 1 },
    });

    before.pages.length = 0;
    after.pages[0].rotation = 180;
    after.selectedPageIds.push("a");

    expect(command.undo(makeState(["ignored"]))).toEqual({
      pages: [
        { id: "a", sourcePageIndex: 0, rotation: 0 },
        { id: "b", sourcePageIndex: 1, rotation: 90 },
      ],
      selectedPageIds: ["a"],
      lastSelectedVisualIndex: 0,
    });

    expect(command.do(makeState(["ignored"]))).toEqual({
      pages: [
        { id: "b", sourcePageIndex: 0, rotation: 0 },
        { id: "a", sourcePageIndex: 1, rotation: 90 },
      ],
      selectedPageIds: ["b"],
      lastSelectedVisualIndex: 0,
    });
  });

  it("round-trips commands through serializable records", () => {
    const before = makeState(["a", "b", "c"]);
    const after: WorkspaceCommandState = {
      pages: [before.pages[2], before.pages[0], before.pages[1]],
      selectedPageIds: ["c"],
      lastSelectedVisualIndex: 0,
    };

    const command = createSnapshotCommand({
      id: "cmd-2",
      type: "copy-pages",
      label: "Copy pages",
      timestamp: "2026-05-17T10:05:00.000Z",
      before,
      after,
    });

    const record = toWorkspaceCommandRecord(command);
    const revived = reviveWorkspaceCommand(record);

    expect(record).not.toHaveProperty("do");
    expect(record).not.toHaveProperty("undo");
    expect(revived.do(before)).toEqual(after);
    expect(revived.undo(after)).toEqual(before);
  });
});