import { z } from "zod";
import { defineTask, TaskRegistry } from "./registry.ts";

// 任务书 §3.1-8 的九类任务。W1 只落空壳:输入 schema + 回显 handler,W2 填充处理器。
// 填充规则见 README「新增/填充任务」:副作用走 withAttemptToken,外部条件用 step.waitForFact,
// 业务状态写业务表,不要放进 handler 返回值。

const id = z.string().min(1);

/** 空壳 handler:记录一条日志并回显输入 */
function stub<I>(name: string) {
  return async (ctx: { input: I; logger: { info(msg: string, f?: Record<string, unknown>): void } }) => {
    // TODO(W2): 实现真实处理器
    ctx.logger.info(`${name}: stub handler (TODO W2)`);
    return { todo: true as const, task: name, input: ctx.input };
  };
}

const NETWORK_RETRY = {
  maximumAttempts: 5,
  initialInterval: "1s",
  backoffCoefficient: 2,
  maximumInterval: "60s",
} as const;
const FILE_RETRY = {
  maximumAttempts: 3,
  initialInterval: "2s",
  backoffCoefficient: 2,
  maximumInterval: "60s",
} as const;
const DB_RETRY = { maximumAttempts: 3, initialInterval: "1s", backoffCoefficient: 2, maximumInterval: "30s" } as const;

export const ingestFeed = defineTask({
  name: "ingestFeed",
  version: 1,
  inputSchema: z.object({ feedSourceId: id }),
  retryPolicy: NETWORK_RETRY,
  handler: stub("ingestFeed"),
});

export const resolveObservation = defineTask({
  name: "resolveObservation",
  version: 1,
  inputSchema: z.object({ observationId: id }),
  retryPolicy: NETWORK_RETRY,
  handler: stub("resolveObservation"),
});

export const evaluateAcquisition = defineTask({
  name: "evaluateAcquisition",
  version: 1,
  inputSchema: z.object({
    subscriptionId: id.optional(),
    acquisitionSlotId: id.optional(),
    sourceReleaseId: id.optional(),
  }),
  retryPolicy: DB_RETRY,
  handler: stub("evaluateAcquisition"),
});

export const submitDownload = defineTask({
  name: "submitDownload",
  version: 1,
  inputSchema: z.object({ acquisitionPlanId: id }),
  retryPolicy: NETWORK_RETRY,
  handler: stub("submitDownload"),
});

export const verifyAndImport = defineTask({
  name: "verifyAndImport",
  version: 1,
  inputSchema: z.object({ downloadTaskId: id }),
  retryPolicy: FILE_RETRY,
  handler: stub("verifyAndImport"),
});

export const refreshMetadata = defineTask({
  name: "refreshMetadata",
  version: 1,
  inputSchema: z.object({ mediaEntityId: id }),
  retryPolicy: NETWORK_RETRY,
  handler: stub("refreshMetadata"),
});

export const reconcileLibrary = defineTask({
  name: "reconcileLibrary",
  version: 1,
  inputSchema: z.object({ libraryRootId: id.optional(), reconcileRunId: id.optional() }),
  retryPolicy: FILE_RETRY,
  handler: stub("reconcileLibrary"),
});

export const cleanupDownloadCache = defineTask({
  name: "cleanupDownloadCache",
  version: 1,
  inputSchema: z.object({ downloaderInstanceId: id.optional() }),
  retryPolicy: FILE_RETRY,
  handler: stub("cleanupDownloadCache"),
});

export const resolveDecision = defineTask({
  name: "resolveDecision",
  version: 1,
  inputSchema: z.object({ decisionId: id }),
  retryPolicy: DB_RETRY,
  handler: stub("resolveDecision"),
});

export const TASK_NAMES = [
  "ingestFeed",
  "resolveObservation",
  "evaluateAcquisition",
  "submitDownload",
  "verifyAndImport",
  "refreshMetadata",
  "reconcileLibrary",
  "cleanupDownloadCache",
  "resolveDecision",
] as const;
export type TaskName = (typeof TASK_NAMES)[number];

/** v0.1 的默认注册表;W2 把真实 handler 换进来(同名同版本替换,或升版本并保留旧版本) */
export function createDefaultRegistry(): TaskRegistry {
  return new TaskRegistry().register(
    ingestFeed,
    resolveObservation,
    evaluateAcquisition,
    submitDownload,
    verifyAndImport,
    refreshMetadata,
    reconcileLibrary,
    cleanupDownloadCache,
    resolveDecision,
  );
}