import { buildControlFrame } from "./control-frame.ts";
import { maybeSeedLitePlan } from "./demand-loop.ts";
import { collectMetadataEvidence, formatMetadataAutocollectResult } from "./metadata-autocollect.ts";
import { advanceRunIfReady, readActiveRun, refreshGate } from "./state.ts";
import type { ActiveRun } from "./types.ts";

export interface DemandSchedulerOutcome {
	handled: boolean;
	run: ActiveRun;
	promptText?: string;
	notices: Array<{ message: string; level: "info" | "warning" }>;
}

export function executeDeterministicNext(cwd: string, run: ActiveRun, userText: string): DemandSchedulerOutcome {
	let current = run;
	const notices: DemandSchedulerOutcome["notices"] = [];
	const progress: string[] = [];

	for (let turn = 0; turn < 6; turn++) {
		const seeded = maybeSeedLitePlan(cwd, current);
		if (seeded.changed) {
			current = seeded.run;
			notices.push({ message: "已根据需求和项目线索生成最小可执行 PLAN。", level: "info" });
			progress.push("已生成最小可执行 PLAN");
			continue;
		}

		if (current.phase === "execute" || current.phase === "verify" || current.phase === "ship") {
			return {
				handled: progress.length > 0,
				run: current,
				promptText: progress.length > 0 ? `${progress.join("；")}。现在执行当前 Demand Loop。` : undefined,
				notices,
			};
		}

		const frame = buildControlFrame(cwd, current, userText);
		if (frame.nextAction.kind === "answer-question") {
			const questionId = frame.openQuestion?.id ?? "Q-001";
			return {
				handled: true,
				run: current,
				notices: [
					...notices,
					{
						message: `需要先回答问题：${frame.nextAction.reason}\n使用 /kd answer ${questionId} <答案>，或直接回复答案。`,
						level: "warning",
					},
				],
			};
		}
		if (frame.nextAction.kind === "advance-phase" && frame.nextAction.executable) {
			const result = advanceRunIfReady(cwd, current);
			current = result.run;
			notices.push({ message: result.message, level: result.advanced || result.run.gate.passed ? "info" : "warning" });
			progress.push(result.message);
			if (result.advanced) continue;
			return {
				handled: true,
				run: current,
				promptText: `当前不能推进：${result.message}。只处理当前阻塞项。`,
				notices,
			};
		}
		if (frame.nextAction.kind === "collect-metadata-evidence") {
			const collected = collectMetadataEvidence(cwd, current);
			if (collected.status !== "collected" && collected.status !== "already-present") {
				return {
					handled: false,
					run: current,
					notices: [...notices, { message: collected.message, level: "warning" }],
				};
			}
			notices.push({ message: formatMetadataAutocollectResult(collected), level: "info" });
			progress.push("元数据证据已就绪");
			current = refreshGate(cwd, readActiveRun(cwd) ?? current);
			continue;
		}

		return {
			handled: progress.length > 0,
			run: current,
			promptText: progress.length > 0 ? `${progress.join("；")}。现在执行当前 Demand Loop。` : undefined,
			notices,
		};
	}

	return {
		handled: true,
		run: current,
		promptText: `${progress.join("；")}。已达到确定性 loop 步数上限，现在执行当前 Demand Loop。`,
		notices,
	};
}