/*
* All or portions of this file Copyright (c) Amazon.com, Inc. or its affiliates or
* its licensors.
*
* For complete copyright and license terms please see the LICENSE at the root of this
* distribution (the "License"). All use of this software is governed by the License,
* or, if provided, by the license below or the license accompanying this file. Do not
* remove or modify any license notices. This file is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
*
*/
#pragma once

namespace Metastream
{
    class DataCache;

    // Currently supported HTTP methods
    enum class HttpMethod
    {
        GET
    };

    typedef struct
    {
        HttpMethod method;
        std::map<std::string, std::string> headers;
        std::string uri;
        std::map<std::string, std::string> query;
        std::string body;
    } HttpRequest;

    typedef struct 
    {
        int code;
        std::map<std::string, std::string> headers;
        std::string body;
    } HttpResponse;
    
    class BaseHttpServer
    {
    public:
        BaseHttpServer(const DataCache* cache)
            : m_cache(cache)
        {
        }
        virtual ~BaseHttpServer() {}

        // Start the HTTP server with the given options
        virtual bool Start(const std::string & civetOptions) = 0;

        // Stop the HTTP Server
        virtual void Stop() = 0;

        // Return a JSON list of all data tables that are exposed.
        HttpResponse GetDataTables() const;

        // Return a JSON list of all data keys that are exposed for a specific table.
        HttpResponse GetDataKeys(const std::string& tableName) const;

        // Return a JSON object containing a particular value.
        HttpResponse GetDataValue(const std::string& tableName, const std::string& key) const;

        // Return a JSON object containing a set of values.
        HttpResponse GetDataValues(const std::string& tableName, const std::vector<std::string>& keys) const;

        //---------------------------------------------------------------------
        // Helper functions

        // Split query into key-value pairs
        static std::map<std::string, std::string> TokenizeQuery(const char* queryString);

        // simple string substitution
        static std::string StrReplace(std::string srcString, const std::string & query, const std::string & replacement);

        // Split a query value if it is a comma separated list (e.g. key=value1,value2,...)
        static std::vector<std::string> SplitValueList(const std::string& value, char separator);

        // Serialize header name-value pairs into a string for writing back to response
        static std::string SerializeHeaders(const std::map<std::string, std::string>& headers);

        // Prepare HTTP status for writing back to response (e.g. "HTTP/1.1 200 OK")
        static std::string HttpStatus(int code);

    private:
        const DataCache* m_cache;
    };
} // namespace Metastream