#!/usr/bin/env node
/**
 * Phase 14 post-fix E2E (B-002): RPC flow verifying loose reinject + defer path.
 */
import { spawn } from "node:child_process";
import { mkdtempSync, readFileSync, writeFileSync, rmSync, existsSync } from "node:fs";
import { tmpdir } from "node:os";
import { join, resolve } from "node:path";
import { fileURLToPath } from "node:url";

const repoRoot = resolve(fileURLToPath(new URL(".", import.meta.url)), "..");
const skillPath = resolve(process.env.B002_SKILL_PATH ?? `${process.env.HOME}/.cursor/skills/fup-blame-commits`);
const extensionPath = join(repoRoot, "src/index.ts");
const globalSettingsPath = join(process.env.HOME ?? "", ".pi/agent/settings.json");
const globalBackupPath = `${globalSettingsPath}.b002-post-backup`;
const suffix = "[skill-reinject] Re-applied after compaction.";

function patchGlobalSettings() {
	if (!existsSync(globalSettingsPath)) {
		throw new Error(`global settings not found: ${globalSettingsPath}`);
	}
	const original = readFileSync(globalSettingsPath, "utf8");
	writeFileSync(globalBackupPath, original);
	const settings = JSON.parse(original);
	settings.skillReinject = {
		...settings.skillReinject,
		enabled: true,
		debug: true,
		autoCompactIntegration: "defer",
		requireRegistered: false,
	};
	writeFileSync(globalSettingsPath, `${JSON.stringify(settings, null, 2)}\n`);
	return original;
}

function restoreGlobalSettings(original) {
	writeFileSync(globalSettingsPath, original);
	rmSync(globalBackupPath, { force: true });
}

const sessionDir = mkdtempSync(join(tmpdir(), "b002-post-session-"));
let originalSettings;
try {
	originalSettings = patchGlobalSettings();
} catch (error) {
	console.error(error instanceof Error ? error.message : error);
	process.exit(2);
}

let nextId = 1;
const pending = new Map();
const diagNotifies = [];
const userMessages = [];
let compactResponse;
let nowInjectSeen = false;
let afterCompactInjectSeen = false;

function send(child, cmd) {
	const id = `req-${nextId++}`;
	child.stdin.write(`${JSON.stringify({ id, ...cmd })}\n`);
	return new Promise((resolvePromise, reject) => {
		const timer = setTimeout(() => {
			pending.delete(id);
			reject(new Error(`timeout waiting for ${cmd.type} (${id})`));
		}, Number(process.env.B002_STEP_TIMEOUT_MS ?? 180_000));
		pending.set(id, {
			resolve: (value) => {
				clearTimeout(timer);
				resolvePromise(value);
			},
			reject: (error) => {
				clearTimeout(timer);
				reject(error);
			},
		});
	});
}

function captureDiagLine(line) {
	if (line.includes("skill-reinject [session_compact]:") || line.includes("skill-reinject [before_agent_start]:")) {
		diagNotifies.push(line.trim());
	}
}

function inspectUserMessage(content) {
	const text = typeof content === "string" ? content : JSON.stringify(content ?? "");
	userMessages.push(text);
	if (text.includes(suffix) && text.includes("fup-blame-commits")) {
		afterCompactInjectSeen = true;
	}
}

const piArgs = [
	"--mode",
	"rpc",
	"-e",
	extensionPath,
	"--skill",
	skillPath,
	"--session-dir",
	sessionDir,
	"--model",
	process.env.B002_MODEL ?? "Eltex-Coder-Senior",
	"--no-session",
];

const child = spawn("pi", piArgs, {
	cwd: repoRoot,
	stdio: ["pipe", "pipe", "pipe"],
	env: process.env,
});

let stdoutBuffer = "";
child.stdout.on("data", (chunk) => {
	stdoutBuffer += chunk.toString("utf8");
	let newlineIndex = stdoutBuffer.indexOf("\n");
	while (newlineIndex >= 0) {
		const line = stdoutBuffer.slice(0, newlineIndex).replace(/\r$/, "");
		stdoutBuffer = stdoutBuffer.slice(newlineIndex + 1);
		if (!line.trim()) {
			newlineIndex = stdoutBuffer.indexOf("\n");
			continue;
		}
		try {
			const record = JSON.parse(line);
			if (record.type === "extension_ui_request" && record.method === "notify") {
				if (typeof record.message === "string") {
					captureDiagLine(record.message);
					if (record.message.includes('re-injected "fup-blame-commits" from disk')) {
						nowInjectSeen = true;
					}
				}
			}
			if (record.type === "message" && record.message?.role === "user") {
				inspectUserMessage(record.message.content);
			}
			if (record.type === "response" && record.id && pending.has(record.id)) {
				pending.get(record.id).resolve(record);
				pending.delete(record.id);
			}
		} catch {
			// ignore non-JSON stdout
		}
		newlineIndex = stdoutBuffer.indexOf("\n");
	}
});

const stderrChunks = [];
child.stderr.on("data", (chunk) => {
	const text = chunk.toString("utf8");
	stderrChunks.push(chunk);
	for (const line of text.split("\n")) {
		captureDiagLine(line);
	}
});

child.on("close", () => {
	for (const { reject } of pending.values()) {
		reject(new Error("pi process exited"));
	}
	pending.clear();
});

async function runFlow() {
	await new Promise((resolvePromise) => setTimeout(resolvePromise, 3000));

	await send(child, { type: "prompt", message: "/skill-reinject on" });
	await send(child, { type: "prompt", message: "/skill:fup-blame-commits" });
	await send(child, { type: "prompt", message: "Reply with exactly: ack" });

	// Push skill block out of likely kept window before compact.
	for (let i = 1; i <= 6; i += 1) {
		await send(child, {
			type: "prompt",
			message: `Filler turn ${i}: reply with exactly filler-${i}`,
		});
	}

	await send(child, { type: "prompt", message: "/skill-reinject now" });
	compactResponse = await send(child, { type: "compact" });
	await send(child, { type: "prompt", message: "Reply with exactly: after-compact" });
}

let flowError;
let exitCode = 1;

try {
	await Promise.race([
		runFlow().then(() => child.stdin.end()),
		new Promise((_, reject) =>
			setTimeout(
				() => reject(new Error(`global timeout after ${process.env.B002_TIMEOUT_MS ?? 600_000}ms`)),
				Number(process.env.B002_TIMEOUT_MS ?? 600_000),
			),
		),
	]);
	exitCode = await new Promise((resolvePromise) => {
		child.on("close", (code) => resolvePromise(code ?? 1));
	});
} catch (error) {
	flowError = error instanceof Error ? error.message : String(error);
	child.kill("SIGTERM");
} finally {
	restoreGlobalSettings(originalSettings);
	rmSync(sessionDir, { recursive: true, force: true });
}

const stderr = Buffer.concat(stderrChunks).toString("utf8");
const parsedDiag = diagNotifies.map((line) => {
	const match = line.match(/skill-reinject \[(session_compact|before_agent_start)\]: (.+)$/);
	if (!match) {
		return { raw: line };
	}
	try {
		return { phase: match[1], snapshot: JSON.parse(match[2]) };
	} catch {
		return { phase: match[1], raw: match[2] };
	}
});

const compactDiag = [...parsedDiag].reverse().find((entry) => entry.phase === "session_compact");
const compactSnapshot = compactDiag?.snapshot;
const skillLeftKept =
	compactSnapshot &&
	Array.isArray(compactSnapshot.tracked) &&
	compactSnapshot.tracked.includes("fup-blame-commits") &&
	Array.isArray(compactSnapshot.kept) &&
	!compactSnapshot.kept.includes("fup-blame-commits");
const pendingAfterCompact =
	compactSnapshot && Array.isArray(compactSnapshot.pending) && compactSnapshot.pending.length > 0;

const checks = {
	nowInjectSeen,
	afterCompactInjectSeen,
	skillLeftKept,
	pendingAfterCompact,
	plannedAfterCompact:
		compactSnapshot &&
		Array.isArray(compactSnapshot.planned) &&
		compactSnapshot.planned.includes("fup-blame-commits"),
};

const pass =
	!flowError &&
	(checks.nowInjectSeen || userMessages.some((m) => m.includes("fup-blame-commits") && m.includes(suffix))) &&
	(checks.afterCompactInjectSeen || (skillLeftKept && (checks.pendingAfterCompact || checks.plannedAfterCompact)));

const summary = {
	pass,
	exitCode,
	flowError,
	skillPath,
	checks,
	compactResponse,
	compactSnapshot,
	diagNotifies,
	parsedDiag,
	userMessageCount: userMessages.length,
	stderrTail: stderr.trim().split("\n").filter((l) => !l.includes("Llama.cpp")).slice(-20).join("\n"),
};

console.log(JSON.stringify(summary, null, 2));
process.exit(pass ? 0 : 1);