import type { ThinkingLevel } from "@earendil-works/pi-agent-core";
import type { ClusterTaskInput, ReviewResult, WorkerResult } from "./types.ts";
import { isSuccessfulWorker, runPiJson, type PiRunEvent, type ProcessPauseControl } from "./worker.ts";

function extractJson(text: string): unknown {
	const fenced = text.match(/```(?:json)?\s*([\s\S]*?)```/i);
	const candidate = fenced?.[1] ?? text.slice(text.indexOf("{"), text.lastIndexOf("}") + 1);
	if (!candidate || !candidate.trim()) return undefined;
	try {
		return JSON.parse(candidate);
	} catch {
		return undefined;
	}
}

function asString(value: unknown): string {
	return typeof value === "string" ? value : "";
}

function asStringArray(value: unknown): string[] {
	return Array.isArray(value) ? value.filter((item): item is string => typeof item === "string") : [];
}

export interface ReviewerOptions {
	cwd: string;
	model: string;
	thinkingLevel?: ThinkingLevel;
	tools?: string[];
	timeoutMs: number;
	signal?: AbortSignal;
	pauseControl?: ProcessPauseControl;
	onEvent?: (event: PiRunEvent) => void;
	apiRetryDelaysMs?: readonly number[];
}

export interface ReviewerExecutionResult {
	review: ReviewResult;
	reviewer: WorkerResult;
}

export async function reviewWorkerResult(
	task: ClusterTaskInput,
	worker: WorkerResult,
	options: ReviewerOptions,
): Promise<ReviewerExecutionResult> {
	const reviewPrompt = [
		"请审核下面的 worker 执行结果。只根据任务目标和验收标准判断，不要修改任何文件。",
		"必须只输出一个 JSON 对象，不要输出 Markdown，不要输出解释文字。",
		"decision 只能是 pass、retry、escalate、ask_user 之一。",
		"pass 表示所有验收标准都满足；retry 表示当前等级有明确可修正的问题；escalate 表示问题需要更强模型；ask_user 表示信息不足、目标冲突或无法安全自动处理。",
		"JSON 格式：{\"decision\":\"pass|retry|escalate|ask_user\",\"reason\":\"...\",\"missingCriteria\":[\"...\"],\"nextInstruction\":\"...\"}",
		"任务：",
		JSON.stringify(
			{
				id: task.id,
				title: task.title,
				taskType: task.taskType,
				task: task.task,
				acceptanceCriteria: task.acceptanceCriteria,
			},
			 null,
			2,
		),
		"worker 结果：",
		JSON.stringify(
			{
				exitCode: worker.exitCode,
				output: worker.output,
				stderr: worker.stderr.slice(-10_000),
				stopReason: worker.stopReason,
				errorMessage: worker.errorMessage,
				usage: worker.usage,
			},
			 null,
			2,
		),
	].join("\n\n");

	const systemPrompt = [
		"你是一个严格的代码任务审核器。",
		"你没有写文件权限，只能检查输入中的执行结果。",
		"不要因为 worker 声称完成就直接通过；必须逐条核对验收标准。",
		"输出必须是可解析的 JSON 对象。",
	].join("\n");

	const reviewer = await runPiJson({
		cwd: options.cwd,
		model: options.model,
		thinkingLevel: options.thinkingLevel,
		tools: options.tools,
		systemPrompt,
		prompt: reviewPrompt,
		timeoutMs: options.timeoutMs,
		signal: options.signal,
		pauseControl: options.pauseControl,
		onEvent: options.onEvent,
		apiRetryDelaysMs: options.apiRetryDelaysMs,
	});

	let review: ReviewResult;
	if (reviewer.exitCode === 124) {
		review = {
			decision: "timeout",
			reason: reviewer.errorMessage || `审核器超过 ${options.timeoutMs}ms 未完成。`,
			missingCriteria: [],
			nextInstruction: "请检查审核器配置或稍后重新运行任务。",
			rawOutput: reviewer.output,
		};
	} else if (!isSuccessfulWorker(reviewer)) {
		review = {
			decision: "error",
			reason: reviewer.errorMessage || reviewer.stderr.slice(-4_000) || `审核器退出码为 ${reviewer.exitCode}`,
			missingCriteria: [],
			nextInstruction: "请检查审核器进程错误后重新运行任务。",
			rawOutput: reviewer.output,
		};
	} else {
		const parsed = extractJson(reviewer.output);
		if (!isRecord(parsed)) {
			review = {
				decision: "error",
				reason: `审核器返回了无效 JSON。${reviewer.errorMessage ? ` ${reviewer.errorMessage}` : ""}`.trim(),
				missingCriteria: [],
				nextInstruction: "请检查审核器原始输出后重新运行任务。",
				rawOutput: reviewer.output,
			};
		} else {
			const decision = parsed.decision;
			if (decision !== "pass" && decision !== "retry" && decision !== "escalate" && decision !== "ask_user") {
				review = {
					decision: "error",
					reason: "审核器返回了未知 decision。",
					missingCriteria: [],
					nextInstruction: "请检查审核器原始输出后重新运行任务。",
					rawOutput: reviewer.output,
				};
			} else {
				review = {
					decision,
					reason: asString(parsed.reason) || "审核器未提供原因。",
					missingCriteria: asStringArray(parsed.missingCriteria),
					nextInstruction: asString(parsed.nextInstruction),
					rawOutput: reviewer.output,
				};
			}
		}
	}

	return { review, reviewer };
}

function isRecord(value: unknown): value is Record<string, unknown> {
	return typeof value === "object" && value !== null && !Array.isArray(value);
}