/* This work is licensed under a Creative Commons CCZero 1.0 Universal License.
 * See http://creativecommons.org/publicdomain/zero/1.0/ for more information. */
/**
 * This client requests all the available servers from the discovery server (see server_discovery.c)
 * and then calls GetEndpoints on the returned list of servers.
 */

#include <stdio.h>
#include <inttypes.h>
#include <stdlib.h>

#ifdef UA_NO_AMALGAMATION
# include "ua_client.h"
# include "ua_config_standard.h"
# include "ua_log_stdout.h"
#else
# include "open62541.h"
#endif

UA_Logger logger = UA_Log_Stdout;

static UA_StatusCode FindServers(const char* discoveryServerUrl, size_t* registeredServerSize, UA_ApplicationDescription** registeredServers) {
    UA_Client *client = UA_Client_new(UA_ClientConfig_standard);
    UA_StatusCode retval = UA_Client_connect(client, discoveryServerUrl);
    if(retval != UA_STATUSCODE_GOOD) {
        UA_Client_delete(client);
        return retval;
    }
    

    UA_FindServersRequest request;
    UA_FindServersRequest_init(&request);

    /*
     * If you want to find specific servers, you can also include the server URIs in the request:
     *
     */
    //request.serverUrisSize = 1;
    //request.serverUris = UA_malloc(sizeof(UA_String));
    //request.serverUris[0] = UA_String_fromChars("open62541.example.server_register");

    //request.localeIdsSize = 1;
    //request.localeIds = UA_malloc(sizeof(UA_String));
    //request.localeIds[0] = UA_String_fromChars("en");

    // now send the request
    UA_FindServersResponse response;
    UA_FindServersResponse_init(&response);
    __UA_Client_Service(client, &request, &UA_TYPES[UA_TYPES_FINDSERVERSREQUEST],
                        &response, &UA_TYPES[UA_TYPES_FINDSERVERSRESPONSE]);

    //UA_Array_delete(request.serverUris, request.serverUrisSize, &UA_TYPES[UA_TYPES_STRING]);
    //UA_Array_delete(request.localeIds, request.localeIdsSize, &UA_TYPES[UA_TYPES_STRING]);

    if(response.responseHeader.serviceResult != UA_STATUSCODE_GOOD) {
        UA_LOG_ERROR(logger, UA_LOGCATEGORY_CLIENT,
                     "FindServers failed with statuscode 0x%08x", response.responseHeader.serviceResult);
        UA_FindServersResponse_deleteMembers(&response);
        UA_Client_disconnect(client);
        UA_Client_delete(client);
        return response.responseHeader.serviceResult;
    }

    *registeredServerSize = response.serversSize;
    *registeredServers = (UA_ApplicationDescription*)UA_Array_new(response.serversSize, &UA_TYPES[UA_TYPES_APPLICATIONDESCRIPTION]);
    for(size_t i=0;i<response.serversSize;i++)
        UA_ApplicationDescription_copy(&response.servers[i], &(*registeredServers)[i]);
    UA_FindServersResponse_deleteMembers(&response);

    UA_Client_disconnect(client);
    UA_Client_delete(client);
    return (int) UA_STATUSCODE_GOOD;
}

static UA_StatusCode GetEndpoints(UA_Client *client, const UA_String* endpointUrl, size_t* endpointDescriptionsSize, UA_EndpointDescription** endpointDescriptions) {
    UA_GetEndpointsRequest request;
    UA_GetEndpointsRequest_init(&request);
    //request.requestHeader.authenticationToken = client->authenticationToken;
    request.requestHeader.timestamp = UA_DateTime_now();
    request.requestHeader.timeoutHint = 10000;
    request.endpointUrl = *endpointUrl; // assume the endpointurl outlives the service call

    UA_GetEndpointsResponse response;
    UA_GetEndpointsResponse_init(&response);
    __UA_Client_Service(client, &request, &UA_TYPES[UA_TYPES_GETENDPOINTSREQUEST],
    &response, &UA_TYPES[UA_TYPES_GETENDPOINTSRESPONSE]);

    if(response.responseHeader.serviceResult != UA_STATUSCODE_GOOD) {
        UA_LOG_ERROR(logger, UA_LOGCATEGORY_CLIENT,
                     "GetEndpointRequest failed with statuscode 0x%08x", response.responseHeader.serviceResult);
        UA_GetEndpointsResponse_deleteMembers(&response);
        return response.responseHeader.serviceResult;
    }

    *endpointDescriptionsSize = response.endpointsSize;
    *endpointDescriptions = (UA_EndpointDescription*)UA_Array_new(response.endpointsSize, &UA_TYPES[UA_TYPES_ENDPOINTDESCRIPTION]);
    for(size_t i=0;i<response.endpointsSize;i++) {
        UA_EndpointDescription_init(&(*endpointDescriptions)[i]);
        UA_EndpointDescription_copy(&response.endpoints[i], &(*endpointDescriptions)[i]);
    }
    UA_GetEndpointsResponse_deleteMembers(&response);
    return UA_STATUSCODE_GOOD;
}

int main(void) {

    UA_ApplicationDescription* applicationDescriptionArray = NULL;
    size_t applicationDescriptionArraySize = 0;

    UA_StatusCode retval = FindServers("opc.tcp://localhost:4840", &applicationDescriptionArraySize, &applicationDescriptionArray);
    if(retval != UA_STATUSCODE_GOOD) {
        UA_LOG_ERROR(logger, UA_LOGCATEGORY_SERVER, "Could not call FindServers service. Is the discovery server started? StatusCode 0x%08x", retval);
        return (int)retval;
    }

    // output all the returned/registered servers
    for (size_t i=0; i<applicationDescriptionArraySize; i++) {
        UA_ApplicationDescription *description = &applicationDescriptionArray[i];
        printf("Server[%lu]: %.*s", (unsigned long)i, (int)description->applicationUri.length, description->applicationUri.data);
        printf("\n\tName: %.*s", (int)description->applicationName.text.length, description->applicationName.text.data);
        printf("\n\tProduct URI: %.*s", (int)description->productUri.length, description->productUri.data);
        printf("\n\tType: ");
        switch(description->applicationType) {
            case UA_APPLICATIONTYPE_SERVER:
                printf("Server");
                break;
            case UA_APPLICATIONTYPE_CLIENT:
                printf("Client");
                break;
            case UA_APPLICATIONTYPE_CLIENTANDSERVER:
                printf("Client and Server");
                break;
            case UA_APPLICATIONTYPE_DISCOVERYSERVER:
                printf("Discovery Server");
                break;
            default:
                printf("Unknown");
        }
        printf("\n\tDiscovery URLs:");
        for (size_t j=0; j<description->discoveryUrlsSize; j++) {
            printf("\n\t\t[%lu]: %.*s", (unsigned long)j, (int)description->discoveryUrls[j].length, description->discoveryUrls[j].data);
        }
        printf("\n\n");
    }


    /*
     * Now that we have the list of available servers, call get endpoints on all of them
     */

    printf("-------- Server Endpoints --------\n");

    for (size_t i=0; i<applicationDescriptionArraySize; i++) {
        UA_ApplicationDescription *description = &applicationDescriptionArray[i];
        if (description->discoveryUrlsSize == 0) {
            UA_LOG_INFO(logger, UA_LOGCATEGORY_CLIENT, "[GetEndpoints] Server %.*s did not provide any discovery urls. Skipping.", description->applicationUri);
            continue;
        }

        printf("\nEndpoints for Server[%lu]: %.*s", (unsigned long)i, (int)description->applicationUri.length, description->applicationUri.data);

        UA_Client *client = UA_Client_new(UA_ClientConfig_standard);

        char* discoveryUrl = malloc(sizeof(char)*description->discoveryUrls[0].length+1);
        memcpy( discoveryUrl, description->discoveryUrls[0].data, description->discoveryUrls[0].length );
        discoveryUrl[description->discoveryUrls[0].length] = '\0';

        retval = UA_Client_connect(client, discoveryUrl);
        free(discoveryUrl);
        if(retval != UA_STATUSCODE_GOOD) {
            UA_Client_delete(client);
            return (int)retval;
        }

        UA_EndpointDescription* endpointArray = NULL;
        size_t endpointArraySize = 0;
        retval = GetEndpoints(client, &description->discoveryUrls[0], &endpointArraySize, &endpointArray);
        if(retval != UA_STATUSCODE_GOOD) {
            UA_Client_disconnect(client);
            UA_Client_delete(client);
            break;
        }

        for(size_t j = 0; j < endpointArraySize; j++) {
            UA_EndpointDescription* endpoint = &endpointArray[j];
            printf("\n\tEndpoint[%lu]:",(unsigned long)j);
            printf("\n\t\tEndpoint URL: %.*s", (int)endpoint->endpointUrl.length, endpoint->endpointUrl.data);
            printf("\n\t\tTransport profile URI: %.*s", (int)endpoint->transportProfileUri.length, endpoint->transportProfileUri.data);
        }

        UA_Array_delete(endpointArray, endpointArraySize, &UA_TYPES[UA_TYPES_ENDPOINTDESCRIPTION]);


        UA_Client_disconnect(client);
        UA_Client_delete(client);
    }

    printf("\n");

    UA_Array_delete(applicationDescriptionArray, applicationDescriptionArraySize, &UA_TYPES[UA_TYPES_APPLICATIONDESCRIPTION]);

    return (int) UA_STATUSCODE_GOOD;
}