import { describe, expect, it } from "vitest";
import {
  MIN_PRESS_TARGET,
  NARROW_BREAKPOINT,
  OVERLAY_ANCHOR_GAP,
  OVERLAY_ATTACH_GAP,
  OVERLAY_BREAKPOINT,
  READING_WIDTH_CH,
  READING_WIDTH_MAX_CH,
  READING_WIDTH_MIN_CH,
  defaultMaxPanes,
  getLayoutSizeClass,
  isTouchSurface,
  layoutBreakpoints,
  layoutSizeClassAtLeast,
  pressTargetHitSlop,
  pressTargetStyle,
  readingWidthStyle,
} from "./layoutTokens";

describe("layoutBreakpoints (DG-LAY-01)", () => {
  it("pivots overlays at medium 640 (Tamagui $sm — MPO-13 C5); expanded 860 stays the pane class", () => {
    expect(layoutBreakpoints.expanded).toBe(860);
    expect(OVERLAY_BREAKPOINT).toBe(640);
    expect(OVERLAY_BREAKPOINT).toBe(layoutBreakpoints.medium);
  });

  it("documents DeskShell narrow as medium 640", () => {
    expect(layoutBreakpoints.medium).toBe(640);
    expect(NARROW_BREAKPOINT).toBe(640);
  });

  it("maps widths to size classes", () => {
    expect(getLayoutSizeClass(360)).toBe("compact");
    expect(getLayoutSizeClass(640)).toBe("medium");
    expect(getLayoutSizeClass(859)).toBe("medium");
    expect(getLayoutSizeClass(860)).toBe("expanded");
    expect(getLayoutSizeClass(1024)).toBe("large");
    expect(getLayoutSizeClass(1280)).toBe("xl");
  });

  it("defaults to 1 pane below expanded, 2 at expanded+", () => {
    expect(defaultMaxPanes("compact")).toBe(1);
    expect(defaultMaxPanes("medium")).toBe(1);
    expect(defaultMaxPanes("expanded")).toBe(2);
    expect(defaultMaxPanes("large")).toBe(2);
    expect(defaultMaxPanes("xl")).toBe(2);
  });

  it("compares size classes ordinally", () => {
    expect(layoutSizeClassAtLeast("expanded", "expanded")).toBe(true);
    expect(layoutSizeClassAtLeast("medium", "expanded")).toBe(false);
    expect(layoutSizeClassAtLeast("xl", "large")).toBe(true);
  });
});

describe("readingWidthStyle (DG-LAY-05)", () => {
  it("defaults to ~70ch within 65–75", () => {
    expect(READING_WIDTH_CH).toBeGreaterThanOrEqual(READING_WIDTH_MIN_CH);
    expect(READING_WIDTH_CH).toBeLessThanOrEqual(READING_WIDTH_MAX_CH);
    expect(readingWidthStyle()).toEqual({ maxWidth: "70ch", width: "100%" });
  });

  it("clamps and supports eject", () => {
    expect(readingWidthStyle(40)).toEqual({ maxWidth: "65ch", width: "100%" });
    expect(readingWidthStyle(90)).toEqual({ maxWidth: "75ch", width: "100%" });
    expect(readingWidthStyle("none")).toEqual({});
    expect(readingWidthStyle(null)).toEqual({});
  });
});

describe("overlay anchoring", () => {
  it("pins the free-overlay gap at 4px and the attach gap at 0", () => {
    expect(OVERLAY_ANCHOR_GAP).toBe(4);
    expect(OVERLAY_ATTACH_GAP).toBe(0);
  });
});

describe("press target (DG-LAY-04)", () => {
  it("exports 44px floor + hitSlop expansion", () => {
    expect(MIN_PRESS_TARGET).toBe(44);
    expect(pressTargetStyle()).toEqual({ minWidth: 44, minHeight: 44 });
    expect(pressTargetHitSlop(24)).toEqual({ top: 10, bottom: 10, left: 10, right: 10 });
    expect(pressTargetHitSlop(44)).toEqual({ top: 0, bottom: 0, left: 0, right: 0 });
  });
});

describe("isTouchSurface (LC-66)", () => {
  it("is false in the default test environment", () => {
    expect(isTouchSurface()).toBe(false);
  });
});