import { afterAll, afterEach, beforeAll, describe, expect, it, vi } from "bun:test";
import * as fs from "node:fs";
import * as os from "node:os";
import * as path from "node:path";
import { getBundledModel } from "@oh-my-pi/pi-catalog/models";
import { ModelRegistry } from "@oh-my-pi/pi-coding-agent/config/model-registry";
import { Settings } from "@oh-my-pi/pi-coding-agent/config/settings";
import {
	type CreateAgentSessionOptions,
	createAgentSession,
	discoverAuthStorage,
	type ExtensionFactory,
} from "@oh-my-pi/pi-coding-agent/sdk";
import { SessionManager } from "@oh-my-pi/pi-coding-agent/session/session-manager";
import { Snowflake } from "@oh-my-pi/pi-utils";
import { z } from "zod/v4";

const toolActivationExtension: ExtensionFactory = pi => {
	pi.registerTool({
		name: "default_inactive_tool",
		label: "Default Inactive Tool",
		description: "Tool hidden from the initial active set unless explicitly requested.",
		parameters: z.object({}),
		defaultInactive: true,
		async execute() {
			return { content: [{ type: "text", text: "inactive" }] };
		},
	});
	pi.registerTool({
		name: "default_active_tool",
		label: "Default Active Tool",
		description: "Tool included in the initial active set.",
		parameters: z.object({}),
		async execute() {
			return { content: [{ type: "text", text: "active" }] };
		},
	});
};

describe("createAgentSession defaultInactive tool activation", () => {
	const tempDirs: string[] = [];

	// Built once and shared by every session. `ModelRegistry` eagerly loads all
	// bundled + cached models and `discoverAuthStorage` opens the auth DB — the
	// dominant (~50ms) slice of a cold boot, and identical for every test here.
	// Injecting it drops each per-test boot to the ~4ms of activation-specific work
	// these tests vary, and skips the background model refresh the SDK would
	// otherwise start when it builds its own registry.
	let modelRegistry!: ModelRegistry;
	let registryAuthDir: string;

	const makeTempDir = (): string => {
		const tempDir = path.join(os.tmpdir(), `pi-sdk-tool-activation-${Snowflake.next()}`);
		tempDirs.push(tempDir);
		fs.mkdirSync(tempDir, { recursive: true });
		return tempDir;
	};

	beforeAll(async () => {
		registryAuthDir = path.join(os.tmpdir(), `pi-sdk-tool-activation-auth-${Snowflake.next()}`);
		fs.mkdirSync(registryAuthDir, { recursive: true });
		modelRegistry = new ModelRegistry(await discoverAuthStorage(registryAuthDir));
	});

	// Shared options for every session. `rules: []` and `workspaceTree` short-circuit
	// the two slow startup scans (rule discovery + native workspace walk, ~100ms each)
	// that are irrelevant to tool activation: these tests assert only which tools are
	// registered/active and that tool names appear in the system prompt. The shared
	// `modelRegistry` is injected here; each call still returns fresh
	// `settings`/`sessionManager` instances to keep tests isolated.
	const baseOptions = (tempDir: string): CreateAgentSessionOptions => ({
		cwd: tempDir,
		agentDir: tempDir,
		modelRegistry,
		sessionManager: SessionManager.inMemory(),
		settings: Settings.isolated(),
		model: getBundledModel("openai", "gpt-4o-mini"),
		disableExtensionDiscovery: true,
		skills: [],
		contextFiles: [],
		promptTemplates: [],
		slashCommands: [],
		enableMCP: false,
		enableLsp: false,
		rules: [],
		workspaceTree: { rootPath: tempDir, rendered: "", truncated: false, totalLines: 0, agentsMdFiles: [] },
	});

	afterEach(() => {
		for (const tempDir of tempDirs.splice(0)) {
			fs.rmSync(tempDir, { recursive: true, force: true });
		}

		vi.restoreAllMocks();
	});

	afterAll(() => {
		fs.rmSync(registryAuthDir, { recursive: true, force: true });
	});

	it("excludes defaultInactive extension tools from the initial active set unless explicitly requested", async () => {
		const tempDir = makeTempDir();

		const { session } = await createAgentSession({
			...baseOptions(tempDir),
			extensions: [toolActivationExtension],
		});

		try {
			expect(session.getAllToolNames()).toEqual(
				expect.arrayContaining(["default_active_tool", "default_inactive_tool"]),
			);
			expect(session.getActiveToolNames()).toContain("default_active_tool");
			expect(session.getActiveToolNames()).not.toContain("default_inactive_tool");
			expect(session.systemPrompt.join("\n")).toContain("default_active_tool");
			expect(session.systemPrompt.join("\n")).not.toContain("default_inactive_tool");
		} finally {
			await session.dispose();
		}
	});

	it("allows explicitly requested defaultInactive extension tools into the initial active set", async () => {
		const tempDir = makeTempDir();

		const { session } = await createAgentSession({
			...baseOptions(tempDir),
			extensions: [toolActivationExtension],
			toolNames: ["read", "default_inactive_tool"],
		});

		try {
			expect(session.getActiveToolNames()).toEqual(
				expect.arrayContaining(["read", "default_active_tool", "default_inactive_tool"]),
			);
			expect(session.systemPrompt.join("\n")).toContain("default_inactive_tool");
		} finally {
			await session.dispose();
		}
	});

	it("activates the yield tool when requireYieldTool is set and toolNames is explicit", async () => {
		// Regression for #1408: plan-mode subagents pass an explicit `toolNames` list
		// (e.g. `["read", "search", "find", "lsp", "web_search"]`). Without this
		// invariant, `yield` ended up registered but not active, and the model
		// could not satisfy the idle-reminder contract that demands a `yield` call.
		const tempDir = makeTempDir();

		const { session } = await createAgentSession({
			...baseOptions(tempDir),
			requireYieldTool: true,
			toolNames: ["read", "search", "find", "web_search"],
		});

		try {
			expect(session.getActiveToolNames()).toContain("yield");
		} finally {
			await session.dispose();
		}
	});

	it("keeps the hidden resolve tool registered for plan mode even when no deferrable tool is requested", async () => {
		// Regression for #1428: plan mode submits its finalized plan via
		// `resolve { action: "apply" }` dispatched through a standing handler
		// (interactive-mode.ts: `setStandingResolveHandler`). With an explicit
		// read-only `toolNames` (e.g. `read`, `search`, `find`, `web_search`)
		// the registry has no `deferrable` tool, so the previous gate dropped
		// `resolve` from the registry and plan mode silently activated without
		// it — leaving the agent stuck after drafting the plan.
		const tempDir = makeTempDir();

		const { session } = await createAgentSession({
			...baseOptions(tempDir),
			toolNames: ["read", "search", "find", "web_search"],
		});

		try {
			expect(session.getToolByName("resolve")).toBeDefined();
		} finally {
			await session.dispose();
		}
	});

	it("drops the hidden resolve tool when neither a deferrable tool nor plan mode can use it", async () => {
		const tempDir = makeTempDir();

		const settings = Settings.isolated();
		settings.set("plan.enabled", false);

		const { session } = await createAgentSession({
			...baseOptions(tempDir),
			settings,
			toolNames: ["read", "search", "find", "web_search"],
		});

		try {
			expect(session.getToolByName("resolve")).toBeUndefined();
		} finally {
			await session.dispose();
		}
	});

	it("does not register the xAI TTS tool unless enabled", async () => {
		const tempDir = makeTempDir();

		const { session } = await createAgentSession({
			...baseOptions(tempDir),
		});

		try {
			expect(session.getToolByName("tts")).toBeUndefined();
			expect(session.getAllToolNames()).not.toContain("tts");
			expect(session.getActiveToolNames()).not.toContain("tts");
		} finally {
			await session.dispose();
		}
	});

	it("registers the xAI TTS tool when enabled", async () => {
		const tempDir = makeTempDir();

		const { session } = await createAgentSession({
			...baseOptions(tempDir),
			settings: Settings.isolated({ "speechgen.enabled": true }),
		});

		try {
			expect(session.getToolByName("tts")).toBeDefined();
			expect(session.getActiveToolNames()).toContain("tts");
		} finally {
			await session.dispose();
		}
	});
});