import { describe, it, expect, vi, beforeEach } from "vitest";
import { Hono } from "hono";
import type { WebAppEnv, ResolvedTheme } from "../../lib/theme-resolution.js";
import { createThemeMiddleware } from "../theme.js";

vi.mock("../../lib/theme-resolution.js", () => ({
  resolveTheme: vi.fn(),
  FALLBACK_THEME: {
    tokens: { "color-bg": "#f5f0e8", "color-primary": "#ff5c00" },
    cssOverrides: null,
    fontUrls: ["https://fonts.googleapis.com/css2?family=Space+Grotesk:wght@400;700&display=swap"],
    colorScheme: "light",
  },
}));

vi.mock("../../lib/logger.js", () => ({
  logger: { debug: vi.fn(), info: vi.fn(), warn: vi.fn(), error: vi.fn(), fatal: vi.fn() },
}));

import { resolveTheme, FALLBACK_THEME } from "../../lib/theme-resolution.js";
import { logger } from "../../lib/logger.js";

const mockResolveTheme = vi.mocked(resolveTheme);
const mockLogger = vi.mocked(logger);

const MOCK_THEME: ResolvedTheme = {
  tokens: { "color-bg": "#ffffff", "color-primary": "#ff5c00" },
  cssOverrides: null,
  fontUrls: ["https://fonts.example.com/font.css"],
  colorScheme: "light",
};

describe("createThemeMiddleware", () => {
  beforeEach(() => {
    mockResolveTheme.mockReset();
    mockResolveTheme.mockResolvedValue(MOCK_THEME);
    mockLogger.error.mockClear();
  });

  it("stores resolved theme in context for downstream handlers", async () => {
    let capturedTheme: ResolvedTheme | undefined;

    const app = new Hono<WebAppEnv>()
      .use("*", createThemeMiddleware("http://appview.test"))
      .get("/test", (c) => {
        capturedTheme = c.get("theme");
        return c.json({ ok: true });
      });

    const res = await app.request("http://localhost/test");
    expect(res.status).toBe(200);
    expect(capturedTheme).toEqual(MOCK_THEME);
  });

  it("passes Cookie header to resolveTheme", async () => {
    const app = new Hono<WebAppEnv>()
      .use("*", createThemeMiddleware("http://appview.test"))
      .get("/test", (c) => c.json({ ok: true }));

    await app.request("http://localhost/test", {
      headers: { Cookie: "atbb-color-scheme=dark; session=abc" },
    });

    expect(mockResolveTheme).toHaveBeenCalledWith(
      expect.any(String),
      "atbb-color-scheme=dark; session=abc",
      undefined
    );
  });

  it("passes Sec-CH-Prefers-Color-Scheme header to resolveTheme", async () => {
    const app = new Hono<WebAppEnv>()
      .use("*", createThemeMiddleware("http://appview.test"))
      .get("/test", (c) => c.json({ ok: true }));

    await app.request("http://localhost/test", {
      headers: { "Sec-CH-Prefers-Color-Scheme": "dark" },
    });

    expect(mockResolveTheme).toHaveBeenCalledWith(
      expect.any(String),
      undefined,
      "dark"
    );
  });

  it("passes appviewUrl to resolveTheme", async () => {
    const app = new Hono<WebAppEnv>()
      .use("*", createThemeMiddleware("http://custom-appview.example.com"))
      .get("/test", (c) => c.json({ ok: true }));

    await app.request("http://localhost/test");

    expect(mockResolveTheme).toHaveBeenCalledWith(
      "http://custom-appview.example.com",
      undefined,
      undefined
    );
  });

  it("calls resolveTheme with undefined when Cookie and color-scheme headers are absent", async () => {
    const app = new Hono<WebAppEnv>()
      .use("*", createThemeMiddleware("http://appview.test"))
      .get("/test", (c) => c.json({ ok: true }));

    await app.request("http://localhost/test");

    expect(mockResolveTheme).toHaveBeenCalledWith(
      "http://appview.test",
      undefined,
      undefined
    );
  });

  it("calls next() so the downstream handler executes", async () => {
    const app = new Hono<WebAppEnv>()
      .use("*", createThemeMiddleware("http://appview.test"))
      .get("/test", (c) => c.json({ message: "handler ran" }));

    const res = await app.request("http://localhost/test");
    expect(res.status).toBe(200);
    const body = await res.json() as { message: string };
    expect(body.message).toBe("handler ran");
  });

  it("catches unexpected throws from resolveTheme, logs the error, and sets FALLBACK_THEME", async () => {
    mockResolveTheme.mockRejectedValueOnce(new TypeError("Unexpected programming error"));

    let capturedTheme: ResolvedTheme | undefined;
    const app = new Hono<WebAppEnv>()
      .use("*", createThemeMiddleware("http://appview.test"))
      .get("/test", (c) => {
        capturedTheme = c.get("theme");
        return c.json({ ok: true });
      });

    // The request must NOT propagate the error — the middleware should catch it
    const res = await app.request("http://localhost/test");
    expect(res.status).toBe(200);
    expect(capturedTheme).toEqual(FALLBACK_THEME);
    expect(mockLogger.error).toHaveBeenCalledWith(
      expect.stringContaining("resolveTheme threw unexpectedly"),
      expect.objectContaining({ operation: "createThemeMiddleware" })
    );
  });
});