/**
 * Contracts: /vibe mode toggle on InteractiveMode.
 *
 * 1. Vibe tools do not exist in the session registry before the mode is entered.
 * 2. Entering registers and activates exactly `read` plus the vibe tools.
 * 3. Exiting unregisters the vibe tools and restores the pre-vibe active toolset
 *    exactly, including the legitimate empty set.
 */
import { afterEach, beforeAll, beforeEach, describe, expect, it, vi } from "bun:test";
import * as path from "node:path";
import { Agent, type AgentTool } from "@oh-my-pi/pi-agent-core";
import { ModelRegistry } from "@oh-my-pi/pi-coding-agent/config/model-registry";
import { resetSettingsForTest, Settings } from "@oh-my-pi/pi-coding-agent/config/settings";
import { InteractiveMode } from "@oh-my-pi/pi-coding-agent/modes/interactive-mode";
import { initTheme } from "@oh-my-pi/pi-coding-agent/modes/theme/theme";
import { AgentSession } from "@oh-my-pi/pi-coding-agent/session/agent-session";
import { AuthStorage } from "@oh-my-pi/pi-coding-agent/session/auth-storage";
import { SessionManager } from "@oh-my-pi/pi-coding-agent/session/session-manager";
import { FileSessionStorage, type WriteTextAtomicOptions } from "@oh-my-pi/pi-coding-agent/session/session-storage";
import { VIBE_TOOL_NAMES } from "@oh-my-pi/pi-coding-agent/tools/vibe";
import { EventBus } from "@oh-my-pi/pi-coding-agent/utils/event-bus";
import { VibeSessionRegistry } from "@oh-my-pi/pi-coding-agent/vibe/runtime";
import { TempDir } from "@oh-my-pi/pi-utils";
import { type } from "arktype";

function stubTool(name: string): AgentTool {
	return {
		name,
		label: name,
		description: `${name} tool`,
		parameters: type({ value: "string" }),
		strict: true,
		async execute() {
			return { content: [{ type: "text", text: `${name} executed` }] };
		},
	};
}

function vibeModeEntryCount(manager: SessionManager): number {
	return manager.getEntries().filter(entry => entry.type === "mode_change" && entry.mode === "vibe").length;
}

class ExitFaultStorage extends FileSessionStorage {
	failNextAtomicWrite = false;
	#readGate:
		| {
				filePath: string;
				started: ReturnType<typeof Promise.withResolvers<void>>;
				release: ReturnType<typeof Promise.withResolvers<void>>;
		  }
		| undefined;

	gateNextRead(filePath: string): { started: Promise<void>; release: () => void } {
		const started = Promise.withResolvers<void>();
		const release = Promise.withResolvers<void>();
		this.#readGate = { filePath, started, release };
		return { started: started.promise, release: release.resolve };
	}

	override async readTextSlices(
		filePath: string,
		prefixBytes: number,
		suffixBytes: number,
	): Promise<[string, string]> {
		const gate = this.#readGate;
		if (gate?.filePath === filePath) {
			this.#readGate = undefined;
			gate.started.resolve();
			await gate.release.promise;
		}
		return super.readTextSlices(filePath, prefixBytes, suffixBytes);
	}

	override async writeTextAtomic(filePath: string, content: string, options?: WriteTextAtomicOptions): Promise<void> {
		if (this.failNextAtomicWrite) {
			this.failNextAtomicWrite = false;
			throw Object.assign(new Error("journal atomic publish failed"), { code: "ENOSPC" });
		}
		await super.writeTextAtomic(filePath, content, options);
	}
}

describe("InteractiveMode vibe mode toggle", () => {
	let tempDir: TempDir;
	let authStorage: AuthStorage;
	let session: AgentSession;
	let mode: InteractiveMode;
	let storage: ExitFaultStorage;

	beforeAll(async () => {
		await initTheme();
	});

	beforeEach(async () => {
		resetSettingsForTest();
		VibeSessionRegistry.resetGlobalForTests();
		tempDir = TempDir.createSync("@pi-vibe-toggle-");
		await Settings.init({ inMemory: true, cwd: tempDir.path() });
		authStorage = await AuthStorage.create(path.join(tempDir.path(), "testauth.db"));
		const modelRegistry = new ModelRegistry(authStorage);
		const model = modelRegistry.find("anthropic", "claude-sonnet-4-5");
		if (!model) throw new Error("Expected claude-sonnet-4-5 to exist in registry");

		const registryTools = [stubTool("read")];

		storage = new ExitFaultStorage();
		session = new AgentSession({
			agent: new Agent({
				initialState: {
					model,
					systemPrompt: ["Test"],
					tools: [],
					messages: [],
				},
			}),
			sessionManager: SessionManager.create(tempDir.path(), tempDir.path(), storage),
			settings: Settings.isolated({}),
			modelRegistry,
			toolRegistry: new Map(registryTools.map(tool => [tool.name, tool])),
			createVibeTools: () => VIBE_TOOL_NAMES.map(stubTool),
		});
		mode = new InteractiveMode(session, "test", undefined, undefined, undefined, undefined, new EventBus());
	});

	afterEach(async () => {
		mode?.stop();
		await session?.dispose();
		VibeSessionRegistry.resetGlobalForTests();
		authStorage?.close();
		tempDir?.removeSync();
		vi.restoreAllMocks();
		resetSettingsForTest();
	});

	it("restores the exact pre-vibe toolset on exit, including an empty one", async () => {
		expect(session.getAllToolNames()).toEqual(["read"]);
		expect(session.getActiveToolNames()).toEqual([]);

		await mode.handleVibeModeCommand();
		expect(mode.vibeModeEnabled).toBe(true);
		const inMode = session.getActiveToolNames();
		expect(inMode).toContain("read");
		for (const name of VIBE_TOOL_NAMES) {
			expect(inMode).toContain(name);
		}
		expect(inMode.toSorted()).toEqual(["read", ...VIBE_TOOL_NAMES].toSorted());
		expect(session.getAllToolNames().toSorted()).toEqual(["read", ...VIBE_TOOL_NAMES].toSorted());

		// Toggle off: the empty previous toolset must come back — vibe tools
		// must not leak past the mode.
		await mode.handleVibeModeCommand();
		expect(mode.vibeModeEnabled).toBe(false);
		expect(session.getActiveToolNames()).toEqual([]);
		expect(session.getAllToolNames()).toEqual(["read"]);
	});

	it("preserves workers and mode metadata on a same-session reload", async () => {
		await mode.init({ suppressWelcomeIntro: true });
		await mode.handleVibeModeCommand();
		await session.sessionManager.ensureOnDisk();
		const sessionFile = session.sessionFile;
		if (!sessionFile) throw new Error("Expected persisted session file");
		const registry = VibeSessionRegistry.global();
		const suspend = vi.spyOn(registry, "suspendScope");
		const terminate = vi.spyOn(registry, "killAll");

		const readGate = storage.gateNextRead(sessionFile);
		const switching = session.switchSession(sessionFile);
		await readGate.started;
		const suspendCallsBeforeRead = suspend.mock.calls.length;
		readGate.release();
		expect(suspendCallsBeforeRead).toBe(1);
		expect(await switching).toBe(true);

		expect(mode.vibeModeEnabled).toBe(true);
		expect(suspend).toHaveBeenCalledTimes(1);
		expect(terminate).not.toHaveBeenCalled();
		expect(vibeModeEntryCount(session.sessionManager)).toBe(1);
	});

	it("suspends the old scope without tombstones when switching to another vibe parent", async () => {
		await mode.init({ suppressWelcomeIntro: true });
		await mode.handleVibeModeCommand();
		await session.sessionManager.ensureOnDisk();
		const originalSessionId = session.sessionManager.getSessionId();
		const targetManager = SessionManager.create(tempDir.path(), tempDir.path());
		targetManager.appendModeChange("vibe");
		await targetManager.ensureOnDisk();
		const targetFile = targetManager.getSessionFile();
		if (!targetFile) throw new Error("Expected target session file");
		await targetManager.close();
		const registry = VibeSessionRegistry.global();
		const suspend = vi.spyOn(registry, "suspendScope");
		const terminate = vi.spyOn(registry, "killAll");

		expect(await session.switchSession(targetFile)).toBe(true);

		expect(mode.vibeModeEnabled).toBe(true);
		expect(suspend).toHaveBeenCalledTimes(1);
		expect(suspend.mock.calls[0]?.[0]).toMatchObject({ parentSessionId: originalSessionId });
		expect(terminate).not.toHaveBeenCalled();
		expect(vibeModeEntryCount(session.sessionManager)).toBe(1);
	});

	it("rejects new, drop, fork, and move transitions at the AgentSession boundary while vibe is active", async () => {
		await mode.init({ suppressWelcomeIntro: true });
		await mode.handleVibeModeCommand();
		await session.sessionManager.ensureOnDisk();
		const sessionFile = session.sessionFile;
		if (!sessionFile) throw new Error("Expected persisted session file");

		await expect(session.newSession()).rejects.toThrow("Exit vibe mode first");
		await expect(session.newSession({ drop: true })).rejects.toThrow("Exit vibe mode first");
		await expect(session.fork()).rejects.toThrow("Exit vibe mode first");
		await expect(session.moveSession(path.join(tempDir.path(), "other-project"))).rejects.toThrow(
			"Exit vibe mode first",
		);
		expect(session.sessionFile).toBe(sessionFile);
		expect(session.sessionManager.getCwd()).toBe(tempDir.path());
		expect(mode.vibeModeEnabled).toBe(true);
	});

	it("keeps vibe mode and tools active after a real storage failure, then allows a retry", async () => {
		await mode.init({ suppressWelcomeIntro: true });
		await mode.handleVibeModeCommand();
		const activeTools = session.getActiveToolNames();
		storage.failNextAtomicWrite = true;

		const exitError = await mode.handleVibeModeCommand().catch(error => error);
		expect(exitError).toBeInstanceOf(Error);
		expect(String(exitError)).toContain("journal atomic publish failed");

		expect(mode.vibeModeEnabled).toBe(true);
		expect(session.getVibeModeState()).toEqual({ enabled: true });
		expect(session.getActiveToolNames()).toEqual(activeTools);
		expect(vibeModeEntryCount(session.sessionManager)).toBe(1);

		await mode.handleVibeModeCommand();
		expect(mode.vibeModeEnabled).toBe(false);
	});
});