import { mkdir, mkdtemp, readFile, rm, writeFile } from "node:fs/promises";
import { createRequire } from "node:module";
import { dirname, join, resolve } from "node:path";
import { fileURLToPath, pathToFileURL } from "node:url";
import { createJiti } from "jiti";
import { describe, expect, it } from "vitest";
import { WSOutboundMessageSchema as GeneratedWSOutboundMessageSchema } from "../../src/generated/validation/ws-outbound.aot.js";

interface GeneratedSchema {
  safeParse(input: unknown): { success: boolean; data?: unknown };
}

const protocolRoot = resolve(dirname(fileURLToPath(import.meta.url)), "../..");
const generatedWSOutboundPath = resolve(
  protocolRoot,
  "src/generated/validation/ws-outbound.aot.ts",
);
const require = createRequire(import.meta.url);

async function compileInlineSchema(sourceSchema: string): Promise<GeneratedSchema> {
  const scratchRoot = resolve(protocolRoot, "../../.tmp");
  await mkdir(scratchRoot, { recursive: true });
  const tempDir = await mkdtemp(join(scratchRoot, "paseo-zod-aot-"));

  try {
    const sourcePath = join(tempDir, "schema.source.js");
    const outputPath = join(tempDir, "schema.generated.ts");
    await writeFile(join(tempDir, "package.json"), '{"type":"module"}\n');
    await writeFile(
      sourcePath,
      [
        'import { z } from "zod";',
        'import { compile } from "zod-aot";',
        sourceSchema,
        "export const Schema = compile(SourceSchema);",
        "",
      ].join("\n"),
    );

    const zodAotEntry = require.resolve("zod-aot");
    const zodAotRoot = resolve(dirname(zodAotEntry), "..");
    const [{ discoverSchemas }, { compileSchemas }, { generateCompiledFileContent }] =
      await Promise.all([
        import(pathToFileURL(resolve(zodAotRoot, "dist/discovery.js")).href),
        import(pathToFileURL(resolve(zodAotRoot, "dist/core/pipeline.js")).href),
        import(pathToFileURL(resolve(zodAotRoot, "dist/cli/emitter.js")).href),
      ]);

    const schemas = await discoverSchemas(sourcePath, { cacheBust: true });
    const compiled = compileSchemas(schemas, { mode: "inline" });
    const content = generateCompiledFileContent(compiled, "./schema.source.js", {
      zodCompat: false,
    });
    await writeFile(outputPath, content);

    const jiti = createJiti(import.meta.url, { moduleCache: false });
    const generated = await jiti.import(outputPath);
    return generated.Schema as GeneratedSchema;
  } finally {
    await rm(tempDir, { recursive: true, force: true });
  }
}

describe("WS outbound zod-aot validation", () => {
  it("applies defaults inside discriminated-union branches", async () => {
    const schema = await compileInlineSchema(`
const SourceSchema = z.discriminatedUnion("type", [
  z.object({
    type: z.literal("with_default"),
    enabled: z.boolean().default(true),
  }),
  z.object({
    type: z.literal("without_default"),
    label: z.string(),
  }),
]);
`);

    expect(schema.safeParse({ type: "with_default" })).toMatchObject({
      success: true,
      data: { type: "with_default", enabled: true },
    });
  });

  it("routes tool-call-like status unions through the current sequential item union", async () => {
    const schema = await compileInlineSchema(`
const ToolCallItemSchema = z.discriminatedUnion("status", [
  z.object({ type: z.literal("tool_call"), status: z.literal("running"), callId: z.string() }),
  z.object({ type: z.literal("tool_call"), status: z.literal("completed"), callId: z.string(), output: z.string() }),
  z.object({ type: z.literal("tool_call"), status: z.literal("failed"), callId: z.string(), error: z.string() }),
  z.object({ type: z.literal("tool_call"), status: z.literal("canceled"), callId: z.string() }),
]);

const TimelineItemSchema = z.union([
  z.object({ type: z.literal("assistant_message"), text: z.string() }),
  ToolCallItemSchema,
]);

const SourceSchema = z.object({
  item: TimelineItemSchema,
});
`);

    expect(
      schema.safeParse({ item: { type: "tool_call", status: "running", callId: "run" } }),
    ).toMatchObject({
      success: true,
      data: { item: { type: "tool_call", status: "running", callId: "run" } },
    });
    expect(
      schema.safeParse({
        item: { type: "tool_call", status: "completed", callId: "done", output: "ok" },
      }),
    ).toMatchObject({
      success: true,
      data: { item: { type: "tool_call", status: "completed", callId: "done", output: "ok" } },
    });
    expect(
      schema.safeParse({
        item: { type: "tool_call", status: "failed", callId: "fail", error: "boom" },
      }),
    ).toMatchObject({
      success: true,
      data: { item: { type: "tool_call", status: "failed", callId: "fail", error: "boom" } },
    });
    expect(
      schema.safeParse({ item: { type: "tool_call", status: "canceled", callId: "stop" } }),
    ).toMatchObject({
      success: true,
      data: { item: { type: "tool_call", status: "canceled", callId: "stop" } },
    });
  });

  it("accepts a minimal valid envelope and rejects a corrupted envelope", () => {
    expect(GeneratedWSOutboundMessageSchema.safeParse({ type: "pong" }).success).toBe(true);
    expect(GeneratedWSOutboundMessageSchema.safeParse({ type: "not_a_message" }).success).toBe(
      false,
    );
  });

  it("emits runtime imports with .js extensions", async () => {
    const generated = await readFile(generatedWSOutboundPath, "utf8");
    expect(generated).toContain('from "../../validation/ws-outbound-schema-metadata.js"');
  });
});