import { type ReactNode, createElement } from "react";
import { renderToString } from "react-dom/server";
import { beforeEach, describe, expect, it, vi } from "vitest";

// Mock Tamagui dependencies to avoid needing a full Tamagui config
vi.mock("tamagui", () => ({
  Theme: ({ name, children }: { name: string; children: ReactNode }) =>
    createElement("div", { "data-tamagui-theme": name }, children),
}));

import type { ThemeName } from "@tamagui/web";
import { Preset } from "./Preset";
import { type PresetContextValue, usePresetContext } from "./PresetContext";
import { defaultKnobs } from "./knobs";
import type { Preset as PresetType } from "./preset.types";
import { clearPresets, registerPreset } from "./shared";

// ---------------------------------------------------------------------------
// Test fixtures
// ---------------------------------------------------------------------------

const boldPreset: PresetType = {
  theme: "blue" as ThemeName,
  knobs: {
    ...defaultKnobs,
    fillStyle: "filled",
    borderRadius: "large",
    elevation: "large",
  },
  intents: {},
  tints: ["blue" as ThemeName, "red" as ThemeName],
};

// ---------------------------------------------------------------------------
// Test helpers
// ---------------------------------------------------------------------------

function createPresetContextCapture() {
  let captured: PresetContextValue | null = null;
  function Capture() {
    captured = usePresetContext();
    return null;
  }
  return {
    Capture,
    get result() {
      return captured;
    },
  };
}

// ---------------------------------------------------------------------------
// Tests
// ---------------------------------------------------------------------------

describe("Preset component", () => {
  beforeEach(() => {
    clearPresets();
  });

  // -------------------------------------------------------------------------
  // 1. Default knobs
  // -------------------------------------------------------------------------
  it("provides default knobs when no preset is specified", () => {
    const capture = createPresetContextCapture();

    renderToString(createElement(Preset, null, createElement(capture.Capture)));

    expect(capture.result?.preset.knobs).toEqual(defaultKnobs);
  });

  // -------------------------------------------------------------------------
  // 2. Overrides merge on top of defaults
  // -------------------------------------------------------------------------
  it("merges overrides on top of defaults", () => {
    const capture = createPresetContextCapture();

    renderToString(
      createElement(
        Preset,
        { overrides: { borderRadius: "full" } },
        createElement(capture.Capture),
      ),
    );

    expect(capture.result?.preset.knobs.borderRadius).toBe("full");
    expect(capture.result?.preset.knobs.fillStyle).toBe(defaultKnobs.fillStyle);
  });

  // -------------------------------------------------------------------------
  // 3. Cascading — child overrides merge on top of parent
  // -------------------------------------------------------------------------
  it("cascades child overrides on top of parent", () => {
    const capture = createPresetContextCapture();

    renderToString(
      createElement(
        Preset,
        { overrides: { borderRadius: "full" } },
        createElement(
          Preset,
          { overrides: { elevation: "large" } },
          createElement(capture.Capture),
        ),
      ),
    );

    expect(capture.result?.preset.knobs.borderRadius).toBe("full");
    expect(capture.result?.preset.knobs.elevation).toBe("large");
  });

  // -------------------------------------------------------------------------
  // 4. cascade=false replaces parent entirely
  // -------------------------------------------------------------------------
  it("cascade={false} replaces parent entirely", () => {
    const capture = createPresetContextCapture();

    renderToString(
      createElement(
        Preset,
        { overrides: { borderRadius: "full" } },
        createElement(
          Preset,
          { cascade: false, overrides: { elevation: "large" } },
          createElement(capture.Capture),
        ),
      ),
    );

    expect(capture.result?.preset.knobs.borderRadius).toBe(defaultKnobs.borderRadius);
    expect(capture.result?.preset.knobs.elevation).toBe("large");
  });

  // -------------------------------------------------------------------------
  // 5. Named preset resolution
  // -------------------------------------------------------------------------
  it("resolves a named preset from the registry", () => {
    registerPreset("bold", boldPreset);
    const capture = createPresetContextCapture();

    renderToString(createElement(Preset, { preset: "bold" }, createElement(capture.Capture)));

    expect(capture.result?.preset.knobs.borderRadius).toBe("large");
    expect(capture.result?.preset.knobs.elevation).toBe("large");
    expect(capture.result?.preset.theme).toBe("blue");
  });

  // -------------------------------------------------------------------------
  // 6. Named preset with overrides
  // -------------------------------------------------------------------------
  it("applies overrides on top of a named preset", () => {
    registerPreset("bold", boldPreset);
    const capture = createPresetContextCapture();

    renderToString(
      createElement(
        Preset,
        { preset: "bold", overrides: { borderRadius: "none" } },
        createElement(capture.Capture),
      ),
    );

    expect(capture.result?.preset.knobs.borderRadius).toBe("none");
    expect(capture.result?.preset.knobs.elevation).toBe("large");
  });

  // -------------------------------------------------------------------------
  // 7. Tamagui <Theme /> wrapping
  // -------------------------------------------------------------------------
  it("wraps children with Tamagui <Theme /> when theme prop is set", () => {
    const capture = createPresetContextCapture();

    const html = renderToString(
      createElement(Preset, { theme: "blue" as ThemeName }, createElement(capture.Capture)),
    );

    expect(html).toContain('data-tamagui-theme="blue"');
  });

  it("does not wrap with Tamagui <Theme /> when theme prop is absent", () => {
    const capture = createPresetContextCapture();

    const html = renderToString(createElement(Preset, null, createElement(capture.Capture)));

    expect(html).not.toContain("data-tamagui-theme");
  });

  // -------------------------------------------------------------------------
  // 8. Cascading named preset inside parent
  // -------------------------------------------------------------------------
  it("cascades a named preset on top of parent overrides", () => {
    registerPreset("bold", boldPreset);
    const capture = createPresetContextCapture();

    renderToString(
      createElement(
        Preset,
        { overrides: { fillStyle: "outlined" } },
        createElement(Preset, { preset: "bold" }, createElement(capture.Capture)),
      ),
    );

    // Named preset replaces base knobs in cascade mode
    expect(capture.result?.preset.knobs.borderRadius).toBe("large");
    // Parent override is carried forward
    expect(capture.result?.preset.knobs.fillStyle).toBe("outlined");
  });

  // -------------------------------------------------------------------------
  // 9. Unknown preset name falls back to defaults
  // -------------------------------------------------------------------------
  it("falls back to default knobs when preset name is not registered", () => {
    const capture = createPresetContextCapture();

    renderToString(
      createElement(Preset, { preset: "nonexistent" }, createElement(capture.Capture)),
    );

    expect(capture.result?.preset.knobs).toEqual(defaultKnobs);
  });

  // -------------------------------------------------------------------------
  // 10. scope prop does not exist on the type
  // -------------------------------------------------------------------------
  it("does not accept scope prop", () => {
    // TypeScript-level check: `scope` should not be part of PresetProps.
    // If this file compiles cleanly, the type check passes.
    // We verify at runtime that passing an unknown prop doesn't break anything.
    const capture = createPresetContextCapture();

    renderToString(
      createElement(
        Preset,
        // @ts-expect-error — scope is intentionally removed from PresetProps
        { scope: "Form" },
        createElement(capture.Capture),
      ),
    );

    expect(capture.result?.preset.knobs).toEqual(defaultKnobs);
  });
});