/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 *  KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <dirent.h>
#include <inttypes.h>

#include "utils.h"
#include "hash_map.h"
#include "bundle_context.h"

#include "celix_log_helper.h"

#include "json_serializer.h"

#include "pubsub_serializer_impl.h"

#define SYSTEM_BUNDLE_ARCHIVE_PATH  "CELIX_FRAMEWORK_EXTENDER_PATH"
#define MAX_PATH_LEN    1024

typedef enum
{
    FIT_INVALID = 0,
    FIT_DESCRIPTOR = 1,
    FIT_AVPR = 2
}
FILE_INPUT_TYPE;

struct pubsub_json_serializer {
    celix_bundle_context_t *bundle_context;
    celix_log_helper_t *log;
};

#define L_DEBUG(...) \
    celix_logHelper_log(serializer->log, CELIX_LOG_LEVEL_DEBUG, __VA_ARGS__)
#define L_INFO(...) \
    celix_logHelper_log(serializer->log, CELIX_LOG_LEVEL_INFO, __VA_ARGS__)
#define L_WARN(...) \
    celix_logHelper_log(serializer->log, CELIX_LOG_LEVEL_WARNING, __VA_ARGS__)
#define L_ERROR(...) \
    celix_logHelper_log(serializer->log, CELIX_LOG_LEVEL_ERROR, __VA_ARGS__)


/* Start of serializer specific functions */
static celix_status_t pubsubMsgSerializer_serialize(void* handle, const void* msg, struct iovec** output, size_t* outputIovLen);
static celix_status_t pubsubMsgSerializer_deserialize(void* handle,const struct iovec* input, size_t inputIovLen, void **out);
static void pubsubMsgSerializer_freeSerializeMsg(void* handle, struct iovec* input, size_t inputIovLen);
static void pubsubMsgSerializer_freeDeserializeMsg(void* handle, void *msg);
static FILE* openFileStream(pubsub_json_serializer_t* serializer, FILE_INPUT_TYPE file_input_type, const char* filename, const char* root, /*output*/ char* avpr_fqn, /*output*/ char* path);
static FILE_INPUT_TYPE getFileInputType(const char* filename);
static bool readPropertiesFile(pubsub_json_serializer_t* serializer, const char* properties_file_name, const char* root, /*output*/ char* avpr_fqn, /*output*/ char* path);

typedef struct pubsub_json_msg_serializer_impl {
    dyn_message_type *msgType;

    unsigned int msgId;
    const char* msgName;
    version_pt msgVersion;
} pubsub_json_msg_serializer_impl_t;

static char* pubsubSerializer_getMsgDescriptionDir(const celix_bundle_t *bundle);
static void pubsubSerializer_addMsgSerializerFromBundle(pubsub_json_serializer_t* serializer, const char *root, const celix_bundle_t *bundle, hash_map_pt msgSerializers);
static void pubsubSerializer_fillMsgSerializerMap(pubsub_json_serializer_t* serializer, hash_map_pt msgSerializers, const celix_bundle_t *bundle);

static int pubsubMsgSerializer_convertDescriptor(pubsub_json_serializer_t* serializer, FILE* file_ptr, pubsub_msg_serializer_t* msgSerializer);
static int pubsubMsgSerializer_convertAvpr(pubsub_json_serializer_t *serializer, FILE* file_ptr, pubsub_msg_serializer_t* msgSerializer, const char* fqn);

static void dfi_log(void *handle, int level, const char *file, int line, const char *msg, ...) {
    va_list ap;
    pubsub_json_serializer_t *serializer = handle;
    char *logStr = NULL;
    va_start(ap, msg);
    vasprintf(&logStr, msg, ap);
    va_end(ap);
    celix_logHelper_log(serializer->log, level, "FILE:%s, LINE:%i, MSG:%s", file, line, logStr);
    free(logStr);
}

celix_status_t pubsubSerializer_create(celix_bundle_context_t *context, pubsub_json_serializer_t** serializer) {
    celix_status_t status = CELIX_SUCCESS;

    *serializer = calloc(1, sizeof(**serializer));

    if (!*serializer) {
        status = CELIX_ENOMEM;
    } else {
        (*serializer)->bundle_context= context;
        (*serializer)->log = celix_logHelper_create(context, "celix_psa_serializer_json");
        jsonSerializer_logSetup(dfi_log, (*serializer), 1);
        dynFunction_logSetup(dfi_log, (*serializer), 1);
        dynType_logSetup(dfi_log, (*serializer), 1);
        dynCommon_logSetup(dfi_log, (*serializer), 1);

    }

    return status;
}

celix_status_t pubsubSerializer_destroy(pubsub_json_serializer_t* serializer) {
    celix_status_t status = CELIX_SUCCESS;

    celix_logHelper_destroy(serializer->log);

    free(serializer);

    return status;
}

celix_status_t pubsubSerializer_createSerializerMap(void *handle, const celix_bundle_t *bundle, hash_map_pt* serializerMap) {
    pubsub_json_serializer_t *serializer = handle;

    hash_map_pt map = hashMap_create(NULL, NULL, NULL, NULL);
    pubsubSerializer_fillMsgSerializerMap(serializer, map, bundle);
    *serializerMap = map;
    return CELIX_SUCCESS;
}

celix_status_t pubsubSerializer_destroySerializerMap(void* handle __attribute__((unused)), hash_map_pt serializerMap) {
    celix_status_t status = CELIX_SUCCESS;
    //pubsub_json_serializer_t *serializer = handle;
    if (serializerMap == NULL) {
        return CELIX_ILLEGAL_ARGUMENT;
    }

    hash_map_iterator_t iter = hashMapIterator_construct(serializerMap);
    while (hashMapIterator_hasNext(&iter)) {
        pubsub_msg_serializer_t* msgSerializer = hashMapIterator_nextValue(&iter);
        pubsub_json_msg_serializer_impl_t *impl = msgSerializer->handle;
        dynMessage_destroy(impl->msgType);
        free(msgSerializer); //also contains the service struct.
        free(impl);
    }

    hashMap_destroy(serializerMap, false, false);

    return status;
}


celix_status_t pubsubMsgSerializer_serialize(void *handle, const void* msg, struct iovec** output, size_t* outputIovLen) {
    celix_status_t status = CELIX_SUCCESS;

    pubsub_json_msg_serializer_impl_t *impl = handle;

    if (*output == NULL) {
        *output = calloc(1, sizeof(struct iovec));
        if (output == NULL) status = CELIX_BUNDLE_EXCEPTION;
    }

    char *jsonOutput = NULL;
    dyn_type* dynType;
    dynMessage_getMessageType(impl->msgType, &dynType);

    if (jsonSerializer_serialize(dynType, msg, &jsonOutput) != 0) {
        status = CELIX_BUNDLE_EXCEPTION;
    }

    if (status == CELIX_SUCCESS) {
        (**output).iov_base = (void*)jsonOutput;
        (**output).iov_len  = strlen(jsonOutput);
        if (outputIovLen) *outputIovLen = 1;
    }

    return status;
}

celix_status_t pubsubMsgSerializer_deserialize(void* handle, const struct iovec* input, size_t inputIovLen __attribute__((unused)), void **out) {
    celix_status_t status = CELIX_SUCCESS;
    if (input == NULL) return CELIX_BUNDLE_EXCEPTION;
    pubsub_json_msg_serializer_impl_t *impl = handle;
    void *msg = NULL;
    dyn_type* dynType;
    dynMessage_getMessageType(impl->msgType, &dynType);

    if (jsonSerializer_deserialize(dynType, (const char*)input->iov_base, input->iov_len, &msg) != 0) {
        status = CELIX_BUNDLE_EXCEPTION;
    }
    else{
        *out = msg;
    }

    return status;
}

void pubsubMsgSerializer_freeSerializeMsg(void* handle, struct iovec* input, size_t inputIovLen) {
    pubsub_json_msg_serializer_impl_t *impl = handle;
    if (input == NULL) {
        return;
    }
    if (impl->msgType != NULL) {
        for (int i = 0; i < inputIovLen; i++) {
            if (input[i].iov_base) free(input[i].iov_base);
            input[i].iov_base = NULL;
            input[i].iov_len  = 0;
        }
        free(input);
    }
}


void pubsubMsgSerializer_freeDeserializeMsg(void* handle, void *msg) {
    pubsub_json_msg_serializer_impl_t *impl = handle;
    if (impl->msgType != NULL) {
        dyn_type* dynType;
        dynMessage_getMessageType(impl->msgType, &dynType);
        dynType_free(dynType, msg);
    }
}


static void pubsubSerializer_fillMsgSerializerMap(pubsub_json_serializer_t* serializer, hash_map_pt msgSerializers, const celix_bundle_t *bundle) {
    char* root = NULL;
    char* metaInfPath = NULL;

    root = pubsubSerializer_getMsgDescriptionDir(bundle);

    if (root != NULL) {
        asprintf(&metaInfPath, "%s/META-INF/descriptors", root);

        pubsubSerializer_addMsgSerializerFromBundle(serializer, root, bundle, msgSerializers);
        pubsubSerializer_addMsgSerializerFromBundle(serializer, metaInfPath, bundle, msgSerializers);

        free(metaInfPath);
        free(root);
    }
}

static char* pubsubSerializer_getMsgDescriptionDir(const celix_bundle_t *bundle) {
    char *root = NULL;

    bool isSystemBundle = false;
    bundle_isSystemBundle(bundle, &isSystemBundle);

    if (isSystemBundle == true) {
        celix_bundle_context_t *context;
        bundle_getContext(bundle, &context);

        const char *prop = NULL;

        bundleContext_getProperty(context, SYSTEM_BUNDLE_ARCHIVE_PATH, &prop);

        if (prop != NULL) {
            root = strdup(prop);
        } else {
            root = getcwd(NULL, 0);
        }
    } else {
        bundle_getEntry(bundle, ".", &root);
    }

    return root;
}

static void pubsubSerializer_addMsgSerializerFromBundle(pubsub_json_serializer_t* serializer, const char *root, const celix_bundle_t *bundle, hash_map_pt msgSerializers) {
    char fqn[MAX_PATH_LEN];
    char pathOrError[MAX_PATH_LEN];
    const char* entry_name = NULL;
    FILE_INPUT_TYPE fileInputType;

    const struct dirent *entry = NULL;
    DIR* dir = opendir(root);
    if (dir) {
        entry = readdir(dir);
    }

    for (; entry != NULL; entry = readdir(dir)) {
        FILE* stream = NULL;
        entry_name = entry->d_name;
        fileInputType = getFileInputType(entry_name);
        if (fileInputType != FIT_INVALID) {
            L_DEBUG("[json serializer] Parsing entry '%s'\n", entry_name);
            stream = openFileStream(serializer, fileInputType, entry_name, root, /*out*/fqn, /*out*/pathOrError);
            if (!stream) {
                L_WARN("[json serializer] Cannot open descriptor file: '%s'\n", pathOrError);
            }
        }

        if (!stream) {
            continue; // Go to next entry in directory
        }

        pubsub_json_msg_serializer_impl_t *impl = calloc(1, sizeof(*impl));
        pubsub_msg_serializer_t *msgSerializer = calloc(1,sizeof(*msgSerializer));
        msgSerializer->handle = impl;

        int translation_result = -1;
        if (fileInputType == FIT_DESCRIPTOR) {
            translation_result = pubsubMsgSerializer_convertDescriptor(serializer, stream, msgSerializer);
        }
        else if (fileInputType == FIT_AVPR) {
            translation_result = pubsubMsgSerializer_convertAvpr(serializer, stream, msgSerializer, fqn);
        }
        fclose(stream);

        if (translation_result != 0) {
            L_WARN("[json serializer] Could not craete serializer for '%s'\n", entry_name);
            free(impl);
            free(msgSerializer);
            continue;
        }

        // serializer has been constructed, try to put in the map
        if (hashMap_containsKey(msgSerializers, (void *) (uintptr_t) msgSerializer->msgId)) {
            L_WARN("Cannot add msg %s. Clash is msg id %d!\n", msgSerializer->msgName, msgSerializer->msgId);
            dynMessage_destroy(impl->msgType);
            free(msgSerializer);
            free(impl);
        } else if (msgSerializer->msgId == 0) {
            L_WARN("Cannot add msg %s. Clash is msg id %d!\n", msgSerializer->msgName, msgSerializer->msgId);
            dynMessage_destroy(impl->msgType);
            free(msgSerializer);
            free(impl);
        }
        else {
            hashMap_put(msgSerializers, (void *) (uintptr_t) msgSerializer->msgId, msgSerializer);
        }
    }

    if (dir) {
        closedir(dir);
    }
}

static FILE* openFileStream(pubsub_json_serializer_t *serializer, FILE_INPUT_TYPE file_input_type, const char* filename, const char* root, char* avpr_fqn, char* pathOrError) {
    FILE* result = NULL;
    memset(pathOrError, 0, MAX_PATH_LEN);
    switch (file_input_type) {
        case FIT_INVALID:
            snprintf(pathOrError, MAX_PATH_LEN, "Because %s is not a valid file", filename);
            break;
        case FIT_DESCRIPTOR:
            snprintf(pathOrError, MAX_PATH_LEN, "%s/%s", root, filename);
            result = fopen(pathOrError, "r");
            break;
        case FIT_AVPR:
            if (readPropertiesFile(serializer, filename, root, avpr_fqn, pathOrError)) {
                result = fopen(pathOrError, "r");
            }
            break;
        default:
            L_WARN("[json serializer] Unknown file input type, returning NULL!\n");
            break;
    }

    return result;
}

static FILE_INPUT_TYPE getFileInputType(const char* filename) {
    if (strstr(filename, ".descriptor")) {
        return FIT_DESCRIPTOR;
    }
    else if (strstr(filename, ".properties")) {
        return FIT_AVPR;
    }
    else {
        return FIT_INVALID;
    }
}

static bool readPropertiesFile(pubsub_json_serializer_t* serializer, const char* properties_file_name, const char* root, char* avpr_fqn, char* path) {
    snprintf(path, MAX_PATH_LEN, "%s/%s", root, properties_file_name); // use path to create path to properties file
    FILE *properties = fopen(path, "r");
    if (!properties) {
        L_WARN("[json serializer] Could not find or open %s as a properties file in %s\n", properties_file_name, root);
        return false;
    }

    *avpr_fqn = '\0';
    *path = '\0'; //re-use path to create path to avpr file
    char *p_line = malloc(MAX_PATH_LEN);
    size_t line_len = MAX_PATH_LEN;
    while (getline(&p_line, &line_len, properties) >= 0) {
        if (strncmp(p_line, "fqn=", strlen("fqn=")) == 0) {
            snprintf(avpr_fqn, MAX_PATH_LEN, "%s", (p_line + strlen("fqn=")));
            avpr_fqn[strcspn(avpr_fqn, "\n")] = 0;
        }
        else if (strncmp(p_line, "avpr=", strlen("avpr=")) == 0) {
            snprintf(path, MAX_PATH_LEN, "%s/%s", root, (p_line + strlen("avpr=")));
            path[strcspn(path, "\n")] = 0;
        }
    }
    free(p_line);
    fclose(properties);

    if (*avpr_fqn == '\0') {
        L_WARN("[json serializer] File %s does not contain a fully qualified name for the parser\n", properties_file_name);
        return false;
    }

    if (*path == '\0') {
        L_WARN("[json serializer] File %s does not contain a location for the avpr file\n", properties_file_name);
        return false;
    }

    return true;
}

static int pubsubMsgSerializer_convertDescriptor(pubsub_json_serializer_t* serializer, FILE* file_ptr, pubsub_msg_serializer_t* msgSerializer) {
    dyn_message_type *msgType = NULL;
    int rc = dynMessage_parse(file_ptr, &msgType);
    if (rc != 0 || msgType == NULL) {
        L_WARN("[json serializer] Cannot parse message from descriptor.\n");
        return -1;
    }

    char *msgName = NULL;
    rc += dynMessage_getName(msgType, &msgName);

    version_pt msgVersion = NULL;
    rc += dynMessage_getVersion(msgType, &msgVersion);

    if (rc != 0 || msgName == NULL || msgVersion == NULL) {
        L_WARN("[json serializer] Cannot retrieve name and/or version from msg\n");
        return -1;
    }

    dyn_type *type = NULL;
    dynMessage_getMessageType(msgType, &type);

    unsigned int msgId = 0;

    char *msgIdStr = NULL;
    int rv = dynMessage_getAnnotationEntry(msgType, "msgId", &msgIdStr);
    if (rv == CELIX_SUCCESS && msgIdStr != NULL) {
        // custom msg id passed, use it
        long customMsgId = strtol(msgIdStr, NULL, 10);
        if (customMsgId > 0)
            msgId = (unsigned int) customMsgId;
    }

    if (msgId == 0) {
        msgId = utils_stringHash(msgName);
    }

    pubsub_json_msg_serializer_impl_t *handle = (pubsub_json_msg_serializer_impl_t*)msgSerializer->handle;
    handle->msgType = msgType;
    handle->msgId = msgId;
    handle->msgName = msgName;
    handle->msgVersion = msgVersion;

    msgSerializer->msgId = handle->msgId;
    msgSerializer->msgName = handle->msgName;
    msgSerializer->msgVersion = handle->msgVersion;

    msgSerializer->serialize = (void*) pubsubMsgSerializer_serialize;
    msgSerializer->deserialize = (void*) pubsubMsgSerializer_deserialize;

    msgSerializer->freeSerializeMsg = (void*) pubsubMsgSerializer_freeSerializeMsg;
    msgSerializer->freeDeserializeMsg = (void*) pubsubMsgSerializer_freeDeserializeMsg;

    return 0;
}

static int pubsubMsgSerializer_convertAvpr(pubsub_json_serializer_t *serializer, FILE* file_ptr, pubsub_msg_serializer_t* msgSerializer, const char* fqn) {
    if (!file_ptr || !fqn || !serializer) return -2;

    //TODO FIXME, see #158
    //dyn_message_type* msgType = dynMessage_parseAvpr(file_ptr, fqn);
    dyn_message_type* msgType = NULL;

    if (!msgType) {
        L_WARN("[json serializer] Cannot parse avpr file '%s'\n", fqn);
        return -1;
    }

    dyn_type* type;
    dynMessage_getMessageType(msgType, &type);

    const char *msgName = dynType_getName(type);

    version_pt msgVersion = NULL;
    celix_status_t s = version_createVersionFromString(dynType_getMetaInfo(type, "version"), &msgVersion);

    if (s != CELIX_SUCCESS || !msgName) {
        L_WARN("[json serializer] Cannot retrieve name and/or version from msg\n");
        if (s == CELIX_SUCCESS) {
            version_destroy(msgVersion);
        }
        return -1;
    }

    unsigned int msgId = 0;
    const char *msgIdStr = dynType_getMetaInfo(type, "msgId");
    if (msgIdStr != NULL) {
        // custom msg id passed, use it
        long customMsgId = strtol(msgIdStr, NULL, 10);
        if (customMsgId > 0)
            msgId = (unsigned int) customMsgId;
    }

    if (msgId == 0) {
        msgId = utils_stringHash(msgName);
    }

    pubsub_json_msg_serializer_impl_t *handle = (pubsub_json_msg_serializer_impl_t*) msgSerializer->handle;
    handle->msgType = msgType;
    handle->msgId = msgId;
    handle->msgName = msgName;
    handle->msgVersion = msgVersion;

    msgSerializer->msgId = handle->msgId;
    msgSerializer->msgName = handle->msgName;
    msgSerializer->msgVersion = handle->msgVersion;

    msgSerializer->serialize = (void*) pubsubMsgSerializer_serialize;
    msgSerializer->deserialize = (void*) pubsubMsgSerializer_deserialize;
    msgSerializer->freeSerializeMsg = (void*) pubsubMsgSerializer_freeSerializeMsg;
    msgSerializer->freeDeserializeMsg = (void*) pubsubMsgSerializer_freeDeserializeMsg;

    return 0;
}