import { stableHash } from "../common/validation.js";
import type { BackendProfile, ExecutionPolicy, JsonRecord, JsonValue, RunRecord, SecretRef } from "../common/types.js";

export interface RunnerJobRenderOptions {
  run: RunRecord;
  commandId: string;
  managerUrl: string;
  image: string;
  namespace?: string;
  attemptId?: string;
  runnerId?: string;
  sourceCommit?: string;
  serviceAccountName?: string;
  imagePullPolicy?: string;
  backoffLimit?: number;
  ttlSecondsAfterFinished?: number;
}

interface CredentialProjection {
  profile: BackendProfile | string;
  secretRef: SecretRef;
  volumeName: string;
  mountPath: string;
}

export function renderRunnerJobDryRun(options: RunnerJobRenderOptions): JsonRecord {
  const render = renderRunnerJobManifest(options);
  return {
    dryRun: true,
    mutation: false,
    action: "render-kubernetes-job",
    jobIdentity: {
      kind: "Job",
      namespace: render.namespace,
      name: render.jobName,
      serviceAccountName: render.serviceAccountName,
    },
    runner: {
      runId: options.run.id,
      commandId: options.commandId,
      attemptId: render.attemptId,
      runnerId: render.runnerId,
      backendProfile: options.run.backendProfile,
      managerUrl: options.managerUrl,
      sourceCommit: render.sourceCommit,
    },
    secretRefs: render.secretRefs.map((item) => ({ profile: item.profile, name: item.secretRef.name, namespace: item.secretRef.namespace ?? render.namespace, keys: item.secretRef.keys ?? [], mountPath: item.mountPath, valuesPrinted: false })),
    pollCommands: {
      run: `bun scripts/agentrun-cli.ts runs show ${options.run.id} --manager-url ${options.managerUrl}`,
      events: `bun scripts/agentrun-cli.ts runs events ${options.run.id} --manager-url ${options.managerUrl} --after-seq 0 --limit 100`,
    },
    warnings: render.warnings,
    manifest: render.manifest,
  };
}

export function renderRunnerJobManifest(options: RunnerJobRenderOptions): { manifest: JsonRecord; namespace: string; jobName: string; runnerId: string; attemptId: string; sourceCommit: string; serviceAccountName: string; secretRefs: CredentialProjection[]; warnings: string[] } {
  const namespace = options.namespace ?? "agentrun-v01";
  const attemptId = options.attemptId ?? `attempt_${Date.now().toString(36)}`;
  const runnerId = options.runnerId ?? `runner_${shortHash(`${options.run.id}:${attemptId}:${options.commandId}`)}`;
  const sourceCommit = options.sourceCommit ?? process.env.AGENTRUN_SOURCE_COMMIT ?? "unknown";
  const serviceAccountName = options.serviceAccountName ?? "agentrun-v01-runner";
  const jobName = `agentrun-v01-runner-${shortDnsHash(options.run.id, attemptId)}`;
  const secretRefs = credentialProjections(options.run, namespace);
  const warnings: string[] = [];
  if (secretRefs.length === 0) warnings.push("run executionPolicy.secretScope 未声明 provider SecretRef；runner 将按 secret-unavailable 上报，而不会降级直连外部凭据");
  const env = runnerEnv(options, { namespace, jobName, runnerId, attemptId, sourceCommit, secretRefs });
  const manifest: JsonRecord = {
    apiVersion: "batch/v1",
    kind: "Job",
    metadata: {
      name: jobName,
      namespace,
      labels: labels(options.run, jobName),
      annotations: {
        "agentrun.pikastech.local/run-id": options.run.id,
        "agentrun.pikastech.local/command-id": options.commandId,
        "agentrun.pikastech.local/dry-run-render": "true",
      },
    },
    spec: {
      backoffLimit: options.backoffLimit ?? 0,
      ttlSecondsAfterFinished: options.ttlSecondsAfterFinished ?? 86_400,
      template: {
        metadata: {
          labels: labels(options.run, jobName),
          annotations: {
            "agentrun.pikastech.local/run-id": options.run.id,
            "agentrun.pikastech.local/command-id": options.commandId,
          },
        },
        spec: {
          serviceAccountName,
          automountServiceAccountToken: false,
          restartPolicy: "Never",
          containers: [
            {
              name: "runner",
              image: options.image,
              imagePullPolicy: options.imagePullPolicy ?? "IfNotPresent",
              command: ["bun", "src/runner/main.ts"],
              env,
              volumeMounts: secretRefs.map((item) => ({ name: item.volumeName, mountPath: item.mountPath, readOnly: true })),
              resources: {
                requests: { cpu: "250m", memory: "512Mi" },
                limits: { cpu: "2", memory: "4Gi" },
              },
              securityContext: {
                allowPrivilegeEscalation: false,
                readOnlyRootFilesystem: false,
                capabilities: { drop: ["ALL"] },
              },
            },
          ],
          volumes: secretRefs.map(secretVolume),
        },
      },
    },
  };
  return { manifest, namespace, jobName, runnerId, attemptId, sourceCommit, serviceAccountName, secretRefs, warnings };
}

function runnerEnv(options: RunnerJobRenderOptions, context: { namespace: string; jobName: string; runnerId: string; attemptId: string; sourceCommit: string; secretRefs: CredentialProjection[] }): JsonRecord[] {
  const codexMount = context.secretRefs.find((item) => item.profile === "codex")?.mountPath ?? "/home/agentrun/.codex";
  return [
    { name: "AGENTRUN_MGR_URL", value: options.managerUrl },
    { name: "AGENTRUN_RUN_ID", value: options.run.id },
    { name: "AGENTRUN_COMMAND_ID", value: options.commandId },
    { name: "AGENTRUN_ATTEMPT_ID", value: context.attemptId },
    { name: "AGENTRUN_RUNNER_ID", value: context.runnerId },
    { name: "AGENTRUN_BACKEND_PROFILE", value: options.run.backendProfile },
    { name: "AGENTRUN_EXECUTION_POLICY_JSON", value: JSON.stringify(options.run.executionPolicy) },
    { name: "AGENTRUN_SOURCE_COMMIT", value: context.sourceCommit },
    { name: "AGENTRUN_RUNTIME_NAMESPACE", value: context.namespace },
    { name: "AGENTRUN_K8S_JOB_NAME", value: context.jobName },
    { name: "AGENTRUN_LOG_PATH", value: "/tmp/agentrun-runner.jsonl" },
    { name: "HOME", value: "/home/agentrun" },
    { name: "CODEX_HOME", value: codexMount },
  ];
}

function credentialProjections(run: RunRecord, namespace: string): CredentialProjection[] {
  const policy: ExecutionPolicy = run.executionPolicy;
  const credentials = policy.secretScope.providerCredentials ?? [];
  return credentials.map((item, index) => ({
    profile: item.profile,
    secretRef: item.secretRef.namespace ? item.secretRef : { ...item.secretRef, namespace },
    volumeName: sanitizeVolumeName(`${String(item.profile)}-${index}`),
    mountPath: normalizeMountPath(item.secretRef.mountPath),
  }));
}

function secretVolume(item: CredentialProjection): JsonRecord {
  const secret: JsonRecord = {
    secretName: item.secretRef.name,
    defaultMode: 256,
  };
  const keys = item.secretRef.keys ?? [];
  if (keys.length > 0) secret.items = keys.map((key) => ({ key, path: key, mode: 256 }));
  return { name: item.volumeName, secret };
}

function normalizeMountPath(value: string | undefined): string {
  if (!value || value === "~/.codex") return "/home/agentrun/.codex";
  if (value.startsWith("~/")) return `/home/agentrun/${value.slice(2)}`;
  return value;
}

function labels(run: RunRecord, jobName: string): JsonRecord {
  return {
    "app.kubernetes.io/name": "agentrun-runner",
    "app.kubernetes.io/component": "runner",
    "app.kubernetes.io/part-of": "agentrun",
    "agentrun.pikastech.local/lane": "v0.1",
    "agentrun.pikastech.local/run-hash": shortHash(run.id),
    "job-name": jobName,
  };
}

function shortDnsHash(...parts: string[]): string {
  return shortHash(parts.join(":"));
}

function shortHash(value: JsonValue): string {
  return stableHash(value).slice(0, 12);
}

function sanitizeVolumeName(value: string): string {
  const sanitized = value.toLowerCase().replace(/[^a-z0-9-]+/gu, "-").replace(/^-+|-+$/gu, "");
  return sanitized.length > 0 ? sanitized.slice(0, 40) : "credential";
}