import type {
  RoleResult,
  StartStep,
  WorkflowDefinition,
  WorkflowMessage,
} from "@uncaged/nerve-core";
import { END } from "@uncaged/nerve-core";
import { createCursorRole, spawnSafe } from "@uncaged/nerve-workflow-utils";
import type { SpawnError } from "@uncaged/nerve-workflow-utils";
import { existsSync, readFileSync } from "node:fs";
import { join } from "node:path";
import { z } from "zod";

// ---------------------------------------------------------------------------
// Constants
// ---------------------------------------------------------------------------

const HOME = process.env.HOME ?? "/home/azureuser";
const NERVE_ROOT = join(HOME, ".uncaged-nerve");
const SENSES_DIR = join(NERVE_ROOT, "senses");

// ---------------------------------------------------------------------------
// Helpers
// ---------------------------------------------------------------------------

function formatSpawnFailure(error: SpawnError): string {
  if (error.kind === "spawn_failed") return error.message;
  if (error.kind === "timeout") return `timeout (stdout=${error.stdout.slice(0, 200)})`;
  return `exit ${error.exitCode} stderr=${error.stderr.slice(0, 400)}`;
}

async function cfgGet(key: string): Promise<string | null> {
  const result = await spawnSafe("cfg", ["get", key], {
    cwd: NERVE_ROOT,
    env: null,
    timeoutMs: 10_000,
  });
  if (!result.ok) return null;
  return result.value.stdout.trim() || null;
}

async function resolveDashScopeProvider(): Promise<{
  baseUrl: string;
  apiKey: string;
  model: string;
} | null> {
  const apiKey = process.env.DASHSCOPE_API_KEY ?? (await cfgGet("DASHSCOPE_API_KEY"));
  const baseUrl = process.env.DASHSCOPE_BASE_URL ?? (await cfgGet("DASHSCOPE_BASE_URL"));
  const model = process.env.DASHSCOPE_MODEL ?? (await cfgGet("DASHSCOPE_MODEL")) ?? "qwen-plus";
  if (!apiKey || !baseUrl) return null;
  return { apiKey, baseUrl, model };
}

function getNerveYaml(): string {
  try {
    return readFileSync(join(NERVE_ROOT, "nerve.yaml"), "utf-8");
  } catch {
    return "# nerve.yaml unavailable";
  }
}

function buildSenseExamples(): string {
  const examples: string[] = [];
  for (const name of ["cpu-usage", "linux-system-health"]) {
    const dir = join(SENSES_DIR, name);
    if (!existsSync(dir)) continue;
    const indexFile = existsSync(join(dir, "index.js"))
      ? readFileSync(join(dir, "index.js"), "utf-8")
      : "";
    const schema = existsSync(join(dir, "schema.ts"))
      ? readFileSync(join(dir, "schema.ts"), "utf-8")
      : "";
    const migrationDir = join(dir, "migrations");
    let migration = "";
    if (existsSync(join(migrationDir, "0001_init.sql"))) {
      migration = readFileSync(join(migrationDir, "0001_init.sql"), "utf-8");
    }
    examples.push(
      `### Example sense: ${name}\n\n` +
        `**index.js:**\n\`\`\`js\n${indexFile}\n\`\`\`\n\n` +
        `**schema.ts:**\n\`\`\`ts\n${schema}\n\`\`\`\n\n` +
        `**migrations/0001_init.sql:**\n\`\`\`sql\n${migration}\n\`\`\``,
    );
  }
  return examples.join("\n\n---\n\n");
}

async function runSenseSmokeTest(
  senseName: string,
): Promise<{ ok: boolean; log: string; reason: string }> {
  const logParts: string[] = [];

  const runNerve = async (
    args: string[],
  ): Promise<{ ok: true; out: string } | { ok: false; err: string }> => {
    const result = await spawnSafe("nerve", args, {
      cwd: NERVE_ROOT,
      env: null,
      timeoutMs: 300_000,
    });
    if (!result.ok) return { ok: false, err: formatSpawnFailure(result.error) };
    return { ok: true, out: result.value.stdout };
  };

  const statusRun = await runNerve(["status"]);
  if (!statusRun.ok) {
    return {
      ok: false,
      log: `=== nerve status ===\nERROR: ${statusRun.err}`,
      reason: `Smoke test command failed: ${statusRun.err}`,
    };
  }
  logParts.push("=== nerve status ===\n" + statusRun.out);
  if (!statusRun.out.includes(senseName)) {
    return {
      ok: false,
      log: logParts.join("\n\n"),
      reason: `Sense "${senseName}" not listed in \`nerve status\` output`,
    };
  }

  const triggerRun = await runNerve(["sense", "trigger", senseName]);
  if (!triggerRun.ok) {
    logParts.push(`=== nerve sense trigger ===\nERROR: ${triggerRun.err}`);
    return { ok: false, log: logParts.join("\n\n"), reason: `Trigger failed: ${triggerRun.err}` };
  }
  logParts.push("=== nerve sense trigger ===\n" + triggerRun.out);

  let lastQuery = "";
  for (let i = 0; i < 25; i++) {
    await new Promise((r) => setTimeout(r, 1000));
    const queryRun = await runNerve(["sense", "query", senseName]);
    if (!queryRun.ok) {
      logParts.push(`=== query attempt ${i + 1} ===\nERROR: ${queryRun.err}`);
    } else {
      lastQuery = queryRun.out;
      logParts.push(`=== query attempt ${i + 1} ===\n${lastQuery}`);
      if (!lastQuery.includes("(0 rows)")) {
        return {
          ok: true,
          log: logParts.join("\n\n"),
          reason: "Trigger succeeded and query returned at least one row",
        };
      }
    }
  }

  return {
    ok: false,
    log: logParts.join("\n\n"),
    reason: lastQuery.includes("(0 rows)")
      ? "Query still returned 0 rows after trigger"
      : "Timed out waiting for successful sense query",
  };
}

// ---------------------------------------------------------------------------
// Meta — routing-only signals for the moderator
// ---------------------------------------------------------------------------

type SenseMeta = {
  planner: { senseName: string };
  coder: { filesCreated: boolean };
  tester: { passed: boolean; attempt: number };
};

// ---------------------------------------------------------------------------
// Bake static context (read once at module load, not per-call)
// ---------------------------------------------------------------------------

const senseExamples = buildSenseExamples();
const nerveYaml = getNerveYaml();

// ---------------------------------------------------------------------------
// Roles
// ---------------------------------------------------------------------------

async function buildPlannerRole() {
  const provider = await resolveDashScopeProvider();
  if (provider === null) {
    throw new Error("Cannot create planner: set DASHSCOPE_API_KEY and DASHSCOPE_BASE_URL");
  }
  return createCursorRole<SenseMeta["planner"]>({
    cwd: NERVE_ROOT,
    mode: "ask",
    prompt: async (threadId) =>
      `You are planning a new Nerve sense.

Read the workflow thread for the user's request: \`nerve thread ${threadId}\`

Pick a good kebab-case name for this sense. Produce a PLAN (not code) in markdown:

## Sense Design
### Name — kebab-case
### Fields — name, type (integer/real/text), description
### Compute Logic — step-by-step, specific Node.js APIs or shell commands
### Trigger Config — group, interval, throttle, timeout

Reference senses:
${senseExamples}

Current nerve.yaml:
\`\`\`yaml
${nerveYaml}
\`\`\`

Output ONLY the plan. Be precise and implementation-ready.`,
    extract: {
      provider,
      schema: z.object({
        senseName: z.string().describe("kebab-case sense name from the plan"),
      }),
    },
  });
}

async function buildCoderRole() {
  const provider = await resolveDashScopeProvider();
  if (provider === null) {
    throw new Error("Cannot create coder: set DASHSCOPE_API_KEY and DASHSCOPE_BASE_URL");
  }
  return createCursorRole<SenseMeta["coder"]>({
    cwd: NERVE_ROOT,
    mode: "default",
    prompt: async (threadId) =>
      `Read the workflow thread for the planner's sense design: \`nerve thread ${threadId}\`

Implement the sense. Create exactly:
1. The sense directory under ${SENSES_DIR}/<sense-name>/
2. index.js — export async function compute(db, _peers), import schema from "./schema.ts"
3. schema.ts — drizzle-orm/sqlite-core
4. migrations/0001_init.sql — must match schema.ts
5. Update ${NERVE_ROOT}/nerve.yaml — add sense config + reflex entry

Follow the patterns from existing senses. Create all files now.`,
    extract: {
      provider,
      schema: z.object({
        filesCreated: z.boolean().describe("true if the sense files were created"),
      }),
    },
  });
}

// Tester: pure CLI logic — stays hand-written
async function tester(
  _start: StartStep,
  messages: WorkflowMessage[],
): Promise<RoleResult<SenseMeta["tester"]>> {
  const attempt = messages.filter((m) => m.role === "tester").length + 1;

  // Get senseName from planner meta
  const plannerStep = messages.find((m) => m.role === "planner");
  const senseName = plannerStep
    ? (plannerStep.meta as SenseMeta["planner"]).senseName
    : "";

  if (senseName.length === 0) {
    return {
      content: "FAIL — no senseName from planner",
      meta: { passed: false, attempt },
    };
  }

  // Check files exist
  const senseDir = join(SENSES_DIR, senseName);
  const missing = [
    existsSync(join(senseDir, "index.js")) ? null : "index.js",
    existsSync(join(senseDir, "schema.ts")) ? null : "schema.ts",
    existsSync(join(senseDir, "migrations", "0001_init.sql")) ? null : "migrations/0001_init.sql",
  ].filter((x) => x !== null);

  if (missing.length > 0) {
    return {
      content: `FAIL — missing files: ${missing.join(", ")}`,
      meta: { passed: false, attempt },
    };
  }

  // Smoke test
  const smoke = await runSenseSmokeTest(senseName);
  return {
    content: `${smoke.ok ? "PASS" : "FAIL"} — ${smoke.reason}`,
    meta: { passed: smoke.ok, attempt },
  };
}

// ---------------------------------------------------------------------------
// Workflow definition
// ---------------------------------------------------------------------------

async function buildWorkflow(): Promise<WorkflowDefinition<SenseMeta>> {
  const plannerRole = await buildPlannerRole();
  const coderRole = await buildCoderRole();

  return {
    name: "sense-generator",
    roles: {
      planner: plannerRole,
      coder: coderRole,
      tester,
    },
    moderator(context) {
      if (context.steps.length === 0) return "planner";
      const last = context.steps[context.steps.length - 1];
      if (last.role === "planner") return "coder";
      if (last.role === "coder") return "tester";
      if (last.role === "tester") {
        if (last.meta.passed) return END;
        return last.meta.attempt < 3 ? "coder" : END;
      }
      return END;
    },
  };
}

const workflow = await buildWorkflow();
export default workflow;