import { afterAll, beforeAll, describe, expect, it } from "vitest";
import http from "node:http";
import type { AddressInfo } from "node:net";
import seedWorkPackages from "@/agentic_pm_demo_codex_plans/data/work-packages.seed.json";
import { parseCommand } from "@/lib/command-parser";
import { resolveChatRequestContext } from "@/lib/chat-request-context";
import type { WorkPackage } from "@/lib/work-package-types";

let server: http.Server;
let baseUrl = "";
const workPackages = seedWorkPackages as WorkPackage[];

function buildFakeLlmResponse(joinedMessages: string) {
  if (joinedMessages.includes("Connection test.")) {
    return "Connected to the configured model.";
  }

  if (joinedMessages.includes('"mode": "ask"')) {
    return "Verification method explains how the requirement will be checked, such as by test, inspection, or analysis.";
  }

  if (joinedMessages.includes('"mode": "plan"')) {
    return "Please break this package into review tasks.";
  }

  if (joinedMessages.includes('"mode": "change"')) {
    return "Please update the objective to include cybersecurity acceptance criteria.";
  }

  return JSON.stringify({
    choices: [
      {
        message: {
          content: JSON.stringify({
            assistantMessage: "Fallback JSON response.",
            boardAction: { type: "none", workPackageId: null },
          }),
        },
      },
    ],
  });
}

beforeAll(async () => {
  server = http.createServer((req, res) => {
    let body = "";
    req.on("data", (chunk) => {
      body += chunk;
    });
    req.on("end", () => {
      let payload: { messages?: Array<{ content?: string }> } = {};
      try {
        payload = JSON.parse(body || "{}");
      } catch {
        payload = {};
      }

      const joinedMessages = (payload.messages ?? [])
        .map((message) => String(message.content ?? ""))
        .join("\n\n");

      res.writeHead(200, { "content-type": "text/plain" });
      res.end(buildFakeLlmResponse(joinedMessages));
    });
  });

  await new Promise<void>((resolve) => {
    server.listen(0, "127.0.0.1", () => {
      const address = server.address() as AddressInfo;
      baseUrl = `http://127.0.0.1:${address.port}/v1`;
      resolve();
    });
  });
});

afterAll(async () => {
  await new Promise<void>((resolve, reject) => {
    server.close((error) => {
      if (error) {
        reject(error);
        return;
      }
      resolve();
    });
  });
});

describe("live model integration routes", () => {
  it("verifies model settings through the connection route", async () => {
    const { POST } = await import("./test-connection/route");

    const response = await POST(
      new Request("http://localhost/api/test-connection", {
        method: "POST",
        headers: { "content-type": "application/json" },
        body: JSON.stringify({
          llmConfig: {
            apiKey: "live-key",
            baseUrl,
            model: "fake-model",
          },
        }),
      }),
    );

    const payload = (await response.json()) as {
      ok?: boolean;
      status?: string;
      message?: string;
    };

    expect(payload.ok).toBe(true);
    expect(payload.status).toBe("connected");
    expect(payload.message).toBe("Connected to the configured model.");
  });

  it("returns a human ask response without board changes when the live model replies in plain text", async () => {
    const { POST } = await import("./chat/route");

    const response = await POST(
      new Request("http://localhost/api/chat", {
        method: "POST",
        headers: { "content-type": "application/json" },
        body: JSON.stringify({
          messages: [
            { role: "user", content: "@SRS ask What does verification method mean?" },
          ],
          workPackages: seedWorkPackages,
          selectedWorkPackageId: "wp-srs",
          parsedCommand: {
            referencedPackageName: "System Requirements Specification",
            mode: "ask",
            instruction: "What does verification method mean?",
          },
          llmConfig: {
            apiKey: "live-key",
            baseUrl,
            model: "fake-model",
          },
        }),
      }),
    );

    const payload = (await response.json()) as {
      assistantMessage: string;
      boardAction?: { type?: string; workPackageId?: string | null };
    };

    expect(payload.assistantMessage).toContain("Verification method explains");
    expect(payload.assistantMessage).not.toContain("Network or parsing error");
    expect(payload.assistantMessage.trim().startsWith("{")).toBe(false);
    expect(payload.boardAction?.type).toBe("none");
    expect(payload.boardAction?.workPackageId).toBeNull();
  });

  it("falls back to a package-scoped plan update when the live model replies in plain text", async () => {
    const { POST } = await import("./chat/route");

    const response = await POST(
      new Request("http://localhost/api/chat", {
        method: "POST",
        headers: { "content-type": "application/json" },
        body: JSON.stringify({
          messages: [
            { role: "user", content: "@SRS plan Break this into review tasks." },
          ],
          workPackages: seedWorkPackages,
          selectedWorkPackageId: "wp-srs",
          parsedCommand: {
            referencedPackageName: "System Requirements Specification",
            mode: "plan",
            instruction: "Break this into review tasks.",
          },
          llmConfig: {
            apiKey: "live-key",
            baseUrl,
            model: "fake-model",
          },
        }),
      }),
    );

    const payload = (await response.json()) as {
      assistantMessage: string;
      boardAction?: {
        type?: string;
        workPackageId?: string | null;
        fields?: { tasks?: unknown[]; status?: string };
      };
    };

    expect(payload.assistantMessage).toContain("Planned next steps for SRS");
    expect(payload.boardAction?.type).toBe("update");
    expect(payload.boardAction?.workPackageId).toBe("wp-srs");
    expect(payload.boardAction?.fields?.tasks?.length).toBeGreaterThan(0);
    expect(payload.boardAction?.fields?.status).toBe("in_progress");
  });

  it("falls back to a package-scoped change update when the live model replies in plain text", async () => {
    const { POST } = await import("./chat/route");

    const response = await POST(
      new Request("http://localhost/api/chat", {
        method: "POST",
        headers: { "content-type": "application/json" },
        body: JSON.stringify({
          messages: [
            {
              role: "user",
              content: "@SRS change Add cybersecurity acceptance criteria.",
            },
          ],
          workPackages: seedWorkPackages,
          selectedWorkPackageId: "wp-srs",
          parsedCommand: {
            referencedPackageName: "System Requirements Specification",
            mode: "change",
            instruction: "Add cybersecurity acceptance criteria.",
          },
          llmConfig: {
            apiKey: "live-key",
            baseUrl,
            model: "fake-model",
          },
        }),
      }),
    );

    const payload = (await response.json()) as {
      assistantMessage: string;
      boardAction?: {
        type?: string;
        workPackageId?: string | null;
        fields?: { objective?: string; status?: string };
      };
    };

    expect(payload.assistantMessage).toContain("Updated SRS");
    expect(payload.boardAction?.type).toBe("update");
    expect(payload.boardAction?.workPackageId).toBe("wp-srs");
    expect(payload.boardAction?.fields?.objective).toContain(
      "Add cybersecurity acceptance criteria",
    );
    expect(payload.boardAction?.fields?.status).toBe("in_progress");
  });

  it("handles slash plan commands through the same selected-package routing chain used by the client", async () => {
    const parsed = parseCommand("/plan Break this into review tasks.", workPackages);
    const selectedWorkPackage = workPackages.find((workPackage) => workPackage.id === "wp-srs");
    const resolved = resolveChatRequestContext({
      parsed: parsed.parsed,
      detailOpen: false,
      selectedWorkPackage,
    });

    expect(resolved.parsedCommand.mode).toBe("plan");
    expect(resolved.parsedCommand.referencedPackageName).toBe(
      selectedWorkPackage?.title,
    );

    const { POST } = await import("./chat/route");
    const response = await POST(
      new Request("http://localhost/api/chat", {
        method: "POST",
        headers: { "content-type": "application/json" },
        body: JSON.stringify({
          messages: [
            { role: "user", content: "/plan Break this into review tasks." },
          ],
          workPackages: seedWorkPackages,
          selectedWorkPackageId: "wp-srs",
          parsedCommand: resolved.parsedCommand,
          llmConfig: {
            apiKey: "live-key",
            baseUrl,
            model: "fake-model",
          },
        }),
      }),
    );

    const payload = (await response.json()) as {
      assistantMessage: string;
      boardAction?: {
        type?: string;
        workPackageId?: string | null;
        fields?: { tasks?: unknown[]; status?: string };
      };
    };

    expect(payload.assistantMessage).toContain("Planned next steps for SRS");
    expect(payload.boardAction?.type).toBe("update");
    expect(payload.boardAction?.workPackageId).toBe("wp-srs");
    expect(payload.boardAction?.fields?.tasks?.length).toBeGreaterThan(0);
    expect(payload.boardAction?.fields?.status).toBe("in_progress");
  });
});