// Copyright (c) Microsoft Corporation. All rights reserved.
// Licensed under the MIT License.

package com.microsoft.aad.msal4j;

import java.util.Collections;
import java.util.HashMap;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.concurrent.CompletableFuture;
import java.util.concurrent.atomic.AtomicReference;

class DeviceCodeFlowRequest extends MsalRequest {

    private AtomicReference<CompletableFuture<IAuthenticationResult>> futureReference;

    private DeviceCodeFlowParameters parameters;
    private String scopesStr;

    DeviceCodeFlowRequest(DeviceCodeFlowParameters parameters,
                          AtomicReference<CompletableFuture<IAuthenticationResult>> futureReference,
                          PublicClientApplication application,
                          RequestContext requestContext) {

        super(application, null, requestContext);

        this.parameters = parameters;
        this.scopesStr = String.join(" ", parameters.scopes());
        this.futureReference = futureReference;
    }

    DeviceCode acquireDeviceCode(String url,
                                 String clientId,
                                 Map<String, String> clientDataHeaders,
                                 ServiceBundle serviceBundle) {

        Map<String, String> headers = appendToHeaders(clientDataHeaders);
        String bodyParams = createQueryParams(clientId);

        HttpRequest httpRequest = new HttpRequest(HttpMethod.POST, url, headers, bodyParams);

        final IHttpResponse response = serviceBundle.getHttpHelper().executeHttpRequest(
                httpRequest,
                this.requestContext(),
                serviceBundle);

        if (response.statusCode() != HttpStatus.HTTP_OK) {
            throw MsalServiceExceptionFactory.fromHttpResponse(response);
        }

        return parseJsonToDeviceCodeAndSetParameters(response.body(), headers, clientId);
    }

    void createAuthenticationGrant(DeviceCode deviceCode) {
        final Map<String, String> params = new LinkedHashMap<>();

        params.put(GrantConstants.GRANT_TYPE_PARAMETER, GrantConstants.DEVICE_CODE);
        params.put("device_code", deviceCode.deviceCode());

        if (parameters.claims() != null) {
            params.put("claims", parameters.claims().formatAsJSONString());
        }

        msalAuthorizationGrant = new OAuthAuthorizationGrant(params, Collections.singleton(deviceCode.scopes()), parameters.claims());
    }

    private String createQueryParams(String clientId) {
        Map<String, String> queryParameters = new HashMap<>();
        queryParameters.put("client_id", clientId);

        String scopesParam = String.join(AbstractMsalAuthorizationGrant.SCOPES_DELIMITER, AbstractMsalAuthorizationGrant.COMMON_SCOPES) +
                AbstractMsalAuthorizationGrant.SCOPES_DELIMITER + scopesStr;

        queryParameters.put("scope", scopesParam);

        return StringHelper.serializeQueryParameters(queryParameters);
    }

    private Map<String, String> appendToHeaders(Map<String, String> clientDataHeaders) {
        Map<String, String> headers = new HashMap<>(clientDataHeaders);
        headers.put("Accept", "application/json");

        return headers;
    }

    private DeviceCode parseJsonToDeviceCodeAndSetParameters(
            String json,
            Map<String, String> headers,
            String clientId) {

        DeviceCode result;
        result = JsonHelper.convertJsonStringToJsonSerializableObject(json, DeviceCode::fromJson);

        String correlationIdHeader = headers.get(HttpHeaders.CORRELATION_ID_HEADER_NAME);
        if (correlationIdHeader != null) {
            result.correlationId(correlationIdHeader);
        }

        result.clientId(clientId);
        result.scopes(scopesStr);

        return result;
    }

    AtomicReference<CompletableFuture<IAuthenticationResult>> futureReference() {
        return this.futureReference;
    }

    DeviceCodeFlowParameters parameters() {
        return this.parameters;
    }

    String scopesStr() {
        return this.scopesStr;
    }
}