import type { Role, RoleResult, StartStep, WorkflowMessage } from "@uncaged/nerve-core";
import { createCursorAdapter } from "@uncaged/nerve-adapter-cursor";
import type { LlmExtractorConfig } from "@uncaged/nerve-workflow-utils";
import { createRole } from "@uncaged/nerve-workflow-utils";
import { z } from "zod";

import { resolveRepoCwd } from "../../lib/repo-context.js";
import { buildImplementPrompt } from "./prompt.js";

export const implementMetaSchema = z.object({
  done: z.boolean().describe("true when changes are complete and build passes this round"),
});
export type ImplementMeta = z.infer<typeof implementMetaSchema>;

export type BuildImplementDeps = {
  extract: LlmExtractorConfig;
  nerveRoot: string;
};

const CURSOR_TIMEOUT_MS = 300_000;

export function buildImplementRole({
  extract,
  nerveRoot,
}: BuildImplementDeps): Role<ImplementMeta> {
  return async (start: StartStep, messages: WorkflowMessage[]): Promise<RoleResult<ImplementMeta>> => {
    const cwd = resolveRepoCwd(messages);
    if (cwd === null) {
      return {
        content: "implement cannot run: missing repo path in thread markers",
        meta: { done: false },
      };
    }

    const innerRole = createRole(
      createCursorAdapter({
        type: "cursor",
        model: "auto",
        timeout: CURSOR_TIMEOUT_MS,
      }),
      async (innerStart: StartStep) =>
        buildImplementPrompt({
          threadId: innerStart.meta.threadId,
          nerveRoot,
        }),
      implementMetaSchema,
      extract,
    );

    const innerStart = {
      ...start,
      meta: { ...start.meta, workdir: cwd },
    } as StartStep;

    try {
      return await innerRole(innerStart, messages);
    } catch (e) {
      const msg = e instanceof Error ? e.message : String(e);
      return {
        content: `implement failed: ${msg}`,
        meta: { done: false },
      };
    }
  };
}