import { END } from "@uncaged/nerve-core";
import type { Moderator } from "@uncaged/nerve-core";
import type { ReadIssueMeta } from "./roles/read-issue/index.js";
import type { PrepareMeta } from "./roles/prepare/index.js";
import type { PlanMeta } from "./roles/plan/index.js";
import type { ImplementMeta } from "./roles/implement/index.js";
import type { ReviewMeta } from "./roles/review/index.js";
import type { TestMeta } from "./roles/test/index.js";
import type { PublishMeta } from "./roles/publish/index.js";

export type WorkflowMeta = {
  "read-issue": ReadIssueMeta;
  prepare: PrepareMeta;
  plan: PlanMeta;
  implement: ImplementMeta;
  review: ReviewMeta;
  test: TestMeta;
  publish: PublishMeta;
};

const MAX_IMPLEMENT_ROUNDS = 20;
const MAX_TOTAL_REJECTIONS = 10;

function implementRounds(steps: { role: string }[]): number {
  return steps.filter((s) => s.role === "implement").length;
}

function totalRejections(steps: { role: string; meta: unknown }[]): number {
  return steps.filter((s) => {
    if (s.role === "review") return !(s.meta as Record<string, boolean>).approved;
    if (s.role === "test") return !(s.meta as Record<string, boolean>).passed;
    if (s.role === "publish") return !(s.meta as Record<string, boolean>).success;
    return false;
  }).length;
}

function canRetryImplement(steps: { role: string; meta: unknown }[]): boolean {
  return implementRounds(steps) < MAX_IMPLEMENT_ROUNDS && totalRejections(steps) < MAX_TOTAL_REJECTIONS;
}

export const moderator: Moderator<WorkflowMeta> = (context) => {
  if (context.steps.length === 0) {
    return "read-issue";
  }

  const last = context.steps[context.steps.length - 1];

  if (last.role === "read-issue") {
    return last.meta.ready ? "prepare" : END;
  }

  if (last.role === "prepare") {
    return last.meta.ready ? "plan" : END;
  }

  if (last.role === "plan") {
    return last.meta.ready ? "implement" : END;
  }

  if (last.role === "implement") {
    if (last.meta.done) {
      return "review";
    }
    return canRetryImplement(context.steps) ? "implement" : END;
  }

  if (last.role === "review") {
    if (last.meta.approved) {
      return "test";
    }
    return canRetryImplement(context.steps) ? "implement" : END;
  }

  if (last.role === "test") {
    if (last.meta.passed) {
      return "publish";
    }
    return canRetryImplement(context.steps) ? "implement" : END;
  }

  if (last.role === "publish") {
    if (last.meta.success) {
      return END;
    }
    return canRetryImplement(context.steps) ? "implement" : END;
  }

  return END;
};