import { mkdirSync, mkdtempSync, rmSync, writeFileSync } from "node:fs";
import { tmpdir } from "node:os";
import path from "node:path";
import { fauxProvider } from "@earendil-works/pi-ai";
import { afterEach, describe, expect, it } from "vitest";
import {
	createPiSession,
	type PiSession,
} from "../../../test/fixture/create-pi-session.ts";
import { __test } from "../index.ts";

const extensionPath = path.resolve(import.meta.dirname, "../index.ts");
const pairs = [{ executor: "openai/gpt-4o", advisor: "openai/gpt-4o" }];

interface NotifyCall {
	args: unknown[];
}

/**
 * Install a recording UI context so `hasUI` is true (the extension sees an
 * interactive UI) and `ctx.ui.notify` calls are captured.
 */
function installRecordingUi(session: PiSession): NotifyCall[] {
	const calls: NotifyCall[] = [];
	session.session.extensionRunner.setUIContext(
		{
			...session.session.extensionRunner.createContext().ui,
			notify: (...args: unknown[]) => calls.push({ args }),
		},
		"print",
	);
	return calls;
}

type Case = { user?: unknown; project?: unknown; untrusted?: boolean };

describe("angel settings resolution", () => {
	let session: PiSession | undefined;
	let root: string | undefined;
	afterEach(async () => {
		await session?.dispose();
		session = undefined;
		if (root) rmSync(root, { recursive: true, force: true });
		root = undefined;
	});

	async function start(input: Case) {
		root = mkdtempSync(path.join(tmpdir(), "pi-ext-angel-settings-"));
		if ("project" in input) {
			mkdirSync(path.join(root, ".pi"), { recursive: true });
			writeFileSync(
				path.join(root, ".pi", "settings.json"),
				JSON.stringify({ angel: input.project }),
			);
		}
		session = await createPiSession({
			cwd: root,
			extensionPaths: [extensionPath],
			...("user" in input ? { userSettings: { angel: input.user } } : {}),
		});
		if (input.untrusted)
			session.session.settingsManager.setProjectTrusted(false);
		// Angel activates only when its configured pairs resolve to real models;
		// provide openai/gpt-4o through a deterministic provider.
		const faux = fauxProvider({
			provider: "openai",
			models: [{ id: "gpt-4o", maxTokens: 8_192 }],
		});
		const registry =
			session.session.extensionRunner.createContext().modelRegistry;
		registry.registerProvider("openai", {
			api: faux.api,
			apiKey: "test-key",
			models: faux.models,
			streamSimple: (model, context, options) =>
				faux.provider.streamSimple(model, context, options),
		});
		await registry.refresh({ allowNetwork: false });
		// Angel resolves its pair against the current model; make it openai/gpt-4o.
		const current = registry.find("openai", "gpt-4o");
		if (!current) throw new Error("missing faux openai/gpt-4o model");
		await session.session.setModel(current);
		const notifications = installRecordingUi(session);
		await session.session.extensionRunner.emit({
			type: "session_start",
			reason: "startup",
		});
		const warnings = notifications
			.filter((call) => call.args[1] === "warning")
			.map((call) => call.args[0]);
		return {
			active: session.session.getActiveToolNames().includes("angel"),
			warnings,
		};
	}

	it.each([
		["default unconfigured", {}, false],
		["user pairs", { user: { pairs } }, true],
		["project pairs", { project: { pairs } }, true],
		[
			"project enabled false merged over user pairs",
			{ user: { pairs }, project: { enabled: false } },
			false,
		],
		[
			"project enabled true merged over user enabled false",
			{ user: { pairs, enabled: false }, project: { enabled: true } },
			true,
		],
		[
			"project pairs array replaces user pairs",
			{ user: { pairs }, project: { pairs: [] } },
			false,
		],
		[
			"untrusted project ignored",
			{ user: { pairs }, project: { enabled: false }, untrusted: true },
			true,
		],
	] satisfies [string, Case, boolean][])(
		"%s",
		async (_name, input, expected) => {
			const { active, warnings } = await start(input);
			expect(active).toBe(expected);
			expect(warnings).toEqual([]);
		},
	);

	it.each([
		[
			"non-object project block",
			{ user: { pairs }, project: true },
			"Invalid angel from project settings: expected an object",
		],
		[
			"merged enabled string",
			{ user: { pairs }, project: { enabled: "false" } },
			"Invalid angel from merged project and user settings: enabled must be a boolean",
		],
		[
			"user thinkingLevel",
			{ user: { pairs, thinkingLevel: "extreme" } },
			"Invalid angel from user settings: thinkingLevel must be one of off, minimal, low, medium, high, xhigh, max",
		],
		[
			"user pair shape",
			{ user: { pairs: [{ executor: "openai/gpt-4o" }] } },
			"Invalid angel from user settings: pairs must be an array of { executor, advisor } strings",
		],
		[
			"user subagentExtensions",
			{ user: { pairs, subagentExtensions: "web" } },
			'Invalid angel from user settings: subagentExtensions must be "all", "none", or a Pi source array',
		],
	] satisfies [string, Case, string][])(
		"rejects %s without falling through",
		async (_name, input, message) => {
			const { active, warnings } = await start(input);
			expect(active).toBe(false);
			expect(warnings).toEqual([`${message}; Angel unconfigured`]);
		},
	);
});

describe("angel sub-agent extensions", () => {
	it("defaults sub-agent extension loading to none", () => {
		expect(__test.resolveSubagentExtensions(undefined)).toBeUndefined();
	});

	it("preserves unique Pi sources without resolving sibling paths", () => {
		expect(
			__test.resolveSubagentExtensions([
				" ./custom-extension.ts ",
				"./custom-extension.ts",
			]),
		).toEqual(["./custom-extension.ts"]);
	});

	it("preserves the all selection", () => {
		expect(__test.resolveSubagentExtensions("all")).toBe("all");
	});
});