import type { ActiveRun, KdToolResultContract, KdWorkingSet, KdWorkingSetFile } from "./types.ts";

const MAX_WORKING_FILES = 12;

export function defaultWorkingSet(run: Pick<ActiveRun, "phase" | "goal">, now = new Date().toISOString()): KdWorkingSet {
	return {
		focus: run.phase,
		activeGap: run.goal,
		currentAction: "读取当前阶段资料并处理最高优先级焦点。",
		recentFiles: [],
		forbiddenDrift: [
			"禁止被最新消息覆盖 open question、resumeSnapshot 或 consistency errors。",
			"禁止把工具摘要当作 FormId、字段、接口映射或验收数据事实。",
			"禁止在 execute 前写产品源码。",
		],
		updatedAt: now,
	};
}

export function updateWorkingSetFromTool(run: ActiveRun, toolResult: KdToolResultContract, now = new Date().toISOString()): KdWorkingSet {
	const current = normalizeWorkingSet(run.workingSet, run, now);
	const nextFiles = mergeRecentFiles(current.recentFiles, filesFromToolResult(toolResult, now));
	return {
		...current,
		currentAction: toolResult.nextAction ?? current.currentAction,
		blockedBy: toolResult.status === "blocked" || toolResult.status === "failed" ? toolResult.summary : current.blockedBy,
		recentFiles: nextFiles,
		updatedAt: now,
	};
}

export function updateWorkingSetFocus(run: ActiveRun, input: { focus: string; activeGap?: string; currentAction?: string; blockedBy?: string }, now = new Date().toISOString()): KdWorkingSet {
	const current = normalizeWorkingSet(run.workingSet, run, now);
	return {
		...current,
		focus: input.focus,
		activeGap: input.activeGap ?? current.activeGap,
		currentAction: input.currentAction ?? current.currentAction,
		blockedBy: Object.prototype.hasOwnProperty.call(input, "blockedBy") ? input.blockedBy : current.blockedBy,
		updatedAt: now,
	};
}

export function formatWorkingSet(workingSet: KdWorkingSet | undefined, run: ActiveRun): string {
	const current = normalizeWorkingSet(workingSet, run);
	const files = current.recentFiles.length > 0 ? current.recentFiles.map((file) => `- ${file.path}：${file.summary}`).join("\n") : "无。";
	return [
		`focus：${current.focus}`,
		current.activeGap ? `activeGap：${current.activeGap}` : undefined,
		current.currentAction ? `currentAction：${current.currentAction}` : undefined,
		current.blockedBy ? `blockedBy：${current.blockedBy}` : undefined,
		"recentFiles：",
		files,
		"forbiddenDrift：",
		...current.forbiddenDrift.map((item) => `- ${item}`),
	].filter(Boolean).join("\n");
}

export function normalizeWorkingSet(value: KdWorkingSet | undefined, run: Pick<ActiveRun, "phase" | "goal">, now = new Date().toISOString()): KdWorkingSet {
	if (!value || typeof value !== "object") return defaultWorkingSet(run, now);
	return {
		focus: typeof value.focus === "string" && value.focus.trim() ? value.focus.trim() : run.phase,
		activeGap: typeof value.activeGap === "string" && value.activeGap.trim() ? value.activeGap.trim() : run.goal,
		currentAction: typeof value.currentAction === "string" && value.currentAction.trim() ? value.currentAction.trim() : undefined,
		blockedBy: typeof value.blockedBy === "string" && value.blockedBy.trim() ? value.blockedBy.trim() : undefined,
		recentFiles: Array.isArray(value.recentFiles) ? value.recentFiles.flatMap(normalizeWorkingSetFile).slice(-MAX_WORKING_FILES) : [],
		forbiddenDrift: Array.isArray(value.forbiddenDrift) ? value.forbiddenDrift.filter((item): item is string => typeof item === "string" && Boolean(item.trim())).map((item) => item.trim()) : defaultWorkingSet(run, now).forbiddenDrift,
		updatedAt: typeof value.updatedAt === "string" ? value.updatedAt : now,
	};
}

function filesFromToolResult(toolResult: KdToolResultContract, now: string): KdWorkingSetFile[] {
	const paths = [...(toolResult.paths ?? []), ...(toolResult.modifiedFiles ?? []), ...(toolResult.evidencePaths ?? [])];
	return [...new Set(paths)]
		.filter((path) => path.trim())
		.map((path) => ({
			path: path.trim(),
			summary: toolResult.summary,
			source: "tool" as const,
			updatedAt: now,
		}));
}

function mergeRecentFiles(existing: KdWorkingSetFile[], incoming: KdWorkingSetFile[]): KdWorkingSetFile[] {
	const byPath = new Map<string, KdWorkingSetFile>();
	for (const file of [...existing, ...incoming]) {
		byPath.set(file.path.replace(/\\/g, "/").toLowerCase(), file);
	}
	return [...byPath.values()].slice(-MAX_WORKING_FILES);
}

function normalizeWorkingSetFile(value: unknown): KdWorkingSetFile[] {
	if (!value || typeof value !== "object" || Array.isArray(value)) return [];
	const record = value as Record<string, unknown>;
	const path = typeof record.path === "string" ? record.path.trim() : "";
	const summary = typeof record.summary === "string" ? record.summary.trim() : "";
	if (!path || !summary) return [];
	return [
		{
			path,
			summary,
			source: record.source === "user" || record.source === "artifact" ? record.source : "tool",
			updatedAt: typeof record.updatedAt === "string" ? record.updatedAt : new Date().toISOString(),
		},
	];
}