// This file is under GNU General Public License 3.0
// see LICENSE.txt

#ifndef LIBPEPADAPTER_MESSAGE_CACHE_HH
#define LIBPEPADAPTER_MESSAGE_CACHE_HH

#include <string>
#include <unordered_map>
#include <mutex>
#include <pEp/message_api.h>
#include <pEp/mime.h>

namespace pEp {
    class MessageCache {
        struct cache_entry {
            cache_entry(::message *s, ::message *d) : src(s), dst(d) {}

            ::message *src;
            ::message *dst;
        };

        using cache = std::unordered_map<std::string, cache_entry>;

        cache _cache;
        std::mutex _mtx;
        long long id_range = 42;
        long long next_id = 23;

    public:
        MessageCache();

        enum which
        {
            msg_src = 0,
            msg_dst = 1
        };

        static PEP_STATUS cache_mime_decode_message(
            const char *mimetext,
            size_t size,
            message **msg,
            bool *has_possible_pEp_msg);

        static PEP_STATUS cache_mime_encode_message(
            int one,
            const message *msg,
            bool omit_fields,
            char **mimetext,
            bool has_pEp_msg_attachment);

        static PEP_STATUS cache_decrypt_message(
            PEP_SESSION session,
            message *src,
            message **dst,
            stringlist_t **keylist,
            PEP_rating *rating,
            PEP_decrypt_flags_t *flags);

        static PEP_STATUS cache_encrypt_message(
            PEP_SESSION session,
            message *src,
            stringlist_t *extra,
            message **dst,
            PEP_enc_format enc_format,
            PEP_encrypt_flags_t flags);

        static PEP_STATUS cache_encrypt_message_for_self(
            PEP_SESSION session,
            pEp_identity *target_id,
            message *src,
            stringlist_t *extra,
            message **dst,
            PEP_enc_format enc_format,
            PEP_encrypt_flags_t flags);


        static PEP_STATUS cache_release(std::string id);
        static void removeCacheID(::message *msg);

    protected:
        void release(std::string id);

        PEP_STATUS mime_decode_message(
            const char *mimetext,
            size_t size,
            message **msg,
            bool *has_possible_pEp_msg);

        PEP_STATUS mime_encode_message(
            which one,
            const message *src,
            bool omit_fields,
            char **mimetext,
            bool has_pEp_msg_attachment);

        PEP_STATUS decrypt_message(
            PEP_SESSION session,
            message *src,
            message **dst,
            stringlist_t **keylist,
            PEP_rating *rating,
            PEP_decrypt_flags_t *flags);

        PEP_STATUS encrypt_message(
            PEP_SESSION session,
            message *src,
            stringlist_t *extra,
            message **dst,
            PEP_enc_format enc_format,
            PEP_encrypt_flags_t flags);

        PEP_STATUS encrypt_message_for_self(
            PEP_SESSION session,
            pEp_identity *target_id,
            message *src,
            stringlist_t *extra,
            message **dst,
            PEP_enc_format enc_format,
            PEP_encrypt_flags_t flags);

        void generateCacheID(::message *msg);
        static std::string cacheID(const ::message *msg);
    };

    extern MessageCache message_cache;
}; // namespace pEp

#endif // LIBPEPADAPTER_MESSAGE_CACHE_HH