import { Diagnostic, resolvePath } from "@typespec/compiler";
import {
	createTestHost,
	createTestWrapper,
	expectDiagnosticEmpty,
} from "@typespec/compiler/testing";
import { TypespecTypescriptEmitterTestLibrary } from "../src/testing/index.js";
import { HttpTestLibrary } from "@typespec/http/testing";

export async function createTypespecTypescriptRoutesTestHost() {
	return createTestHost({
		libraries: [TypespecTypescriptEmitterTestLibrary, HttpTestLibrary],
	});
}

export async function createTypespecTypescriptRoutesTestRunner() {
	const host = await createTypespecTypescriptRoutesTestHost();

	return createTestWrapper(host, {
		autoImports: ["@typespec/http"],
		autoUsings: ["TypeSpec.Http"],
		compilerOptions: {
			noEmit: false,
			emit: ["typespec-typescript-emitter"],
			options: {
				"@gpichot/typespec-typescript-emitter": {
					"root-namespace": "TestNamespace",
					"enable-types": true,
					"enable-routed-typemap": true,
				},
			},
		},
	});
}

export async function emitWithDiagnostics(
	code: string,
): Promise<[Record<string, string>, readonly Diagnostic[]]> {
	const runner = await createTypespecTypescriptRoutesTestRunner();
	await runner.compileAndDiagnose(code, {
		outputDir: "tsp-output",
	});
	const emitterOutputDir = "./tsp-output/@gpichot/typespec-typescript-emitter";
	const files = await runner.program.host.readDir(emitterOutputDir);

	const result: Record<string, string> = {};
	for (const file of files) {
		result[file] = (
			await runner.program.host.readFile(resolvePath(emitterOutputDir, file))
		).text;
	}
	return [result, runner.program.diagnostics];
}

export async function emit(code: string): Promise<Record<string, string>> {
	const [result, diagnostics] = await emitWithDiagnostics(code);
	expectDiagnosticEmpty(diagnostics);
	return result;
}