import { spawn } from "node:child_process";
import { AgentRunError } from "../common/errors.js";
import { redactJson, redactText } from "../common/redaction.js";
import { isTerminalCommandState, isTerminalRunStatus, summarizeResourceBundleRef, summarizeSessionRef } from "./store.js";
import type { AgentRunStore } from "./store.js";
import type { JsonRecord } from "../common/types.js";
import { stableHash, validateEnvName } from "../common/validation.js";
import { renderRunnerJobManifest } from "../runner/k8s-job.js";
import type { RunnerTransientEnv } from "../runner/k8s-job.js";

export interface RunnerJobDefaults {
  namespace: string;
  managerUrl: string;
  image: string;
  sourceCommit: string;
  serviceAccountName?: string;
  kubectlCommand?: string;
}

export interface CreateRunnerJobInput extends JsonRecord {
  commandId: string;
  managerUrl?: string;
  image?: string;
  namespace?: string;
  attemptId?: string;
  runnerId?: string;
  sourceCommit?: string;
  serviceAccountName?: string;
  idempotencyKey?: string;
  transientEnv?: JsonRecord[];
}

export async function createKubernetesRunnerJob(options: { store: AgentRunStore; runId: string; input: CreateRunnerJobInput; defaults: RunnerJobDefaults }): Promise<JsonRecord> {
  const commandId = stringField(options.input, "commandId");
  const run = await options.store.getRun(options.runId);
  const command = await options.store.getCommand(commandId);
  if (command.runId !== run.id) throw new AgentRunError("schema-invalid", `command ${commandId} does not belong to run ${run.id}`, { httpStatus: 400 });
  if (command.type !== "turn") throw new AgentRunError("schema-invalid", `command ${commandId} is not a turn command`, { httpStatus: 400 });

  const image = optionalString(options.input.image) ?? options.defaults.image;
  if (!image) throw new AgentRunError("schema-invalid", "runner job image is required; set --image or AGENTRUN_RUNNER_IMAGE", { httpStatus: 400 });
  const namespace = optionalString(options.input.namespace) ?? options.defaults.namespace;
  const managerUrl = optionalString(options.input.managerUrl) ?? options.defaults.managerUrl;
  const sourceCommit = optionalString(options.input.sourceCommit) ?? options.defaults.sourceCommit;
  const serviceAccountName = optionalString(options.input.serviceAccountName) ?? options.defaults.serviceAccountName;
  const idempotencyKey = optionalString(options.input.idempotencyKey);
  const transientEnv = transientEnvField(options.input.transientEnv);
  const normalizedPayload = {
    commandId,
    image,
    namespace,
    managerUrl,
    sourceCommit,
    serviceAccountName: serviceAccountName ?? null,
    attemptId: optionalString(options.input.attemptId) ?? null,
    runnerId: optionalString(options.input.runnerId) ?? null,
    transientEnv: transientEnv.map((item) => ({ name: item.name, valueHash: stableHash(item.value), sensitive: true })),
  };
  const payloadHash = stableHash(normalizedPayload);
  if (idempotencyKey) {
    const existing = await options.store.getRunnerJobByIdempotencyKey(run.id, idempotencyKey, payloadHash);
    if (existing) return { ...existing.result, idempotentReplay: true };
  }
  if (isTerminalRunStatus(run.status)) throw new AgentRunError(run.failureKind ?? (run.status === "cancelled" ? "cancelled" : "schema-invalid"), `run ${run.id} is already terminal: ${run.status}`, { httpStatus: 409 });
  if (isTerminalCommandState(command.state) || command.state !== "pending") throw new AgentRunError(command.state === "cancelled" ? "cancelled" : "schema-invalid", `command ${commandId} is not pending: ${command.state}`, { httpStatus: 409 });

  const renderOptions = {
    run,
    commandId,
    managerUrl,
    image,
    namespace,
    sourceCommit,
    transientEnv,
    ...(serviceAccountName ? { serviceAccountName } : {}),
  };
  const attemptId = optionalString(options.input.attemptId);
  const runnerId = optionalString(options.input.runnerId);
  const render = renderRunnerJobManifest({ ...renderOptions, ...(attemptId ? { attemptId } : {}), ...(runnerId ? { runnerId } : {}) });
  const created = await kubectlCreate(render.manifest, options.defaults.kubectlCommand ?? "kubectl");
  const response = {
    action: "create-kubernetes-job",
    mutation: true,
    runId: run.id,
    commandId,
    attemptId: render.attemptId,
    runnerId: render.runnerId,
    namespace: render.namespace,
    jobName: render.jobName,
    jobIdentity: {
      kind: "Job",
      namespace: render.namespace,
      name: render.jobName,
      serviceAccountName: render.serviceAccountName,
      uid: objectPath(created, ["metadata", "uid"]),
    },
    runner: {
      runId: run.id,
      commandId,
      attemptId: render.attemptId,
      runnerId: render.runnerId,
      backendProfile: run.backendProfile,
      managerUrl,
      sourceCommit,
      placement: "kubernetes-job",
      logPath: `kubectl -n ${render.namespace} logs job/${render.jobName}`,
    },
    secretRefs: render.secretRefs.map((item) => ({ profile: item.profile, name: item.secretRef.name, namespace: item.secretRef.namespace ?? render.namespace, keys: item.secretRef.keys ?? [], mountPath: item.runtimeMountPath, projectionPath: item.projectionMountPath, writableCopy: true, valuesPrinted: false })),
    toolCredentials: summarizeToolCredentials(render.toolCredentials, render.namespace),
    transientEnv: summarizeTransientEnv(transientEnv),
    retention: {
      ttlSecondsAfterFinished: render.ttlSecondsAfterFinished,
    },
    pollCommands: {
      run: `./scripts/agentrun runs show ${run.id} --manager-url ${managerUrl}`,
      command: `./scripts/agentrun commands show ${commandId} --run-id ${run.id} --manager-url ${managerUrl}`,
      events: `./scripts/agentrun runs events ${run.id} --manager-url ${managerUrl} --after-seq 0 --limit 100`,
    },
    warnings: render.warnings,
    kubernetes: {
      created: true,
      valuesPrinted: false,
      apiVersion: objectPath(created, ["apiVersion"]),
      kind: objectPath(created, ["kind"]),
      resourceVersion: objectPath(created, ["metadata", "resourceVersion"]),
    },
  } satisfies JsonRecord;
  const saved = await options.store.saveRunnerJob({
    runId: run.id,
    commandId,
    idempotencyKey: idempotencyKey ?? null,
    payloadHash,
    attemptId: render.attemptId,
    runnerId: render.runnerId,
    namespace: render.namespace,
    jobName: render.jobName,
    managerUrl,
    image,
    sourceCommit,
    serviceAccountName: serviceAccountName ?? null,
    result: response,
  });
  await options.store.appendEvent(run.id, "backend_status", {
    phase: "runner-job-created",
    commandId,
    attemptId: saved.attemptId,
    runnerId: saved.runnerId,
    namespace: saved.namespace,
    jobName: saved.jobName,
    idempotencyKey: idempotencyKey ? "present" : null,
    transientEnv: summarizeTransientEnv(transientEnv),
    toolCredentials: summarizeToolCredentials(render.toolCredentials, render.namespace),
    sessionRef: summarizeSessionRef(run.sessionRef ?? null),
    resourceBundleRef: summarizeResourceBundleRef(run.resourceBundleRef ?? null),
  });
  return response;
}

function transientEnvField(value: unknown): RunnerTransientEnv[] {
  if (value === undefined) return [];
  if (!Array.isArray(value)) throw new AgentRunError("schema-invalid", "transientEnv must be an array", { httpStatus: 400 });
  if (value.length > 8) throw new AgentRunError("schema-invalid", "transientEnv must contain at most 8 entries", { httpStatus: 400 });
  const seen = new Set<string>();
  return value.map((entry, index) => {
    if (!entry || typeof entry !== "object" || Array.isArray(entry)) throw new AgentRunError("schema-invalid", `transientEnv[${index}] must be an object`, { httpStatus: 400 });
    const record = entry as JsonRecord;
    const name = stringField(record, "name");
    validateEnvName(name, `transientEnv[${index}].name`);
    if (name === "GH_TOKEN" || name === "GITHUB_TOKEN" || name === "OPENAI_API_KEY" || name === "CODEX_API_KEY") throw new AgentRunError("tenant-policy-denied", `transientEnv ${name} must use tool/provider credential assembly instead`, { httpStatus: 403 });
    if (seen.has(name)) throw new AgentRunError("schema-invalid", `transientEnv name ${name} is duplicated`, { httpStatus: 400 });
    seen.add(name);
    const rawValue = record.value;
    if (typeof rawValue !== "string" || rawValue.length === 0) throw new AgentRunError("schema-invalid", `transientEnv[${index}].value must be a non-empty string`, { httpStatus: 400 });
    if (Buffer.byteLength(rawValue, "utf8") > 8192) throw new AgentRunError("schema-invalid", `transientEnv[${index}].value is too large`, { httpStatus: 400 });
    return { name, value: rawValue, sensitive: true };
  });
}

function summarizeToolCredentials(items: Array<{ tool: string; purpose: string | null; secretRef: { namespace?: string; name: string; keys?: string[] }; envName: string; secretKey: string }>, namespace: string): JsonRecord {
  return {
    count: items.length,
    items: items.map((item) => ({
      tool: item.tool,
      purpose: item.purpose,
      name: item.secretRef.name,
      namespace: item.secretRef.namespace ?? namespace,
      keys: item.secretRef.keys ?? [],
      projection: { kind: "env", envName: item.envName, secretKey: item.secretKey },
      valuesPrinted: false,
    })),
    valuesPrinted: false,
  };
}

function summarizeTransientEnv(items: RunnerTransientEnv[]): JsonRecord {
  return {
    count: items.length,
    names: items.map((item) => item.name),
    valuesPrinted: false,
  };
}

async function kubectlCreate(manifest: JsonRecord, kubectlCommand: string): Promise<JsonRecord> {
  const child = spawn(kubectlCommand, ["create", "-f", "-", "-o", "json"], { stdio: ["pipe", "pipe", "pipe"] });
  let stdout = "";
  let stderr = "";
  child.stdout.setEncoding("utf8");
  child.stderr.setEncoding("utf8");
  child.stdout.on("data", (chunk) => { stdout += String(chunk); });
  child.stderr.on("data", (chunk) => { stderr += String(chunk); });
  child.stdin.end(`${JSON.stringify(manifest)}\n`);
  const result = await new Promise<{ code: number | null; signal: NodeJS.Signals | null }>((resolve, reject) => {
    child.on("error", reject);
    child.on("close", (code, signal) => resolve({ code, signal }));
  }).catch((error: unknown) => {
    throw new AgentRunError("infra-failed", `failed to start kubectl: ${error instanceof Error ? error.message : String(error)}`, { httpStatus: 503 });
  });
  if (result.code !== 0) {
    throw new AgentRunError("infra-failed", `kubectl create runner job failed with code ${result.code}`, { httpStatus: 502, details: redactJson({ stderr: redactText(stderr.slice(-4000)), stdout: redactText(stdout.slice(-2000)), signal: result.signal }) });
  }
  try {
    const parsed = JSON.parse(stdout) as unknown;
    if (typeof parsed === "object" && parsed !== null && !Array.isArray(parsed)) return redactJson(parsed as JsonRecord);
  } catch (error) {
    throw new AgentRunError("infra-failed", `kubectl returned invalid JSON: ${error instanceof Error ? error.message : String(error)}`, { httpStatus: 502, details: { stdoutPreview: redactText(stdout.slice(0, 1000)) } });
  }
  throw new AgentRunError("infra-failed", "kubectl returned non-object JSON", { httpStatus: 502 });
}

function stringField(record: JsonRecord, key: string): string {
  const value = record[key];
  if (typeof value !== "string" || value.trim().length === 0) throw new AgentRunError("schema-invalid", `${key} is required`, { httpStatus: 400 });
  return value.trim();
}

function optionalString(value: unknown): string | undefined {
  return typeof value === "string" && value.trim().length > 0 ? value.trim() : undefined;
}

function objectPath(value: unknown, path: string[]): string | null {
  let current: unknown = value;
  for (const key of path) {
    if (typeof current !== "object" || current === null || Array.isArray(current)) return null;
    current = (current as Record<string, unknown>)[key];
  }
  return typeof current === "string" ? current : null;
}