/*
* Copyright (c) 2025 Aldrik Ramaekers <aldrik.ramaekers@gmail.com>
* 
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
* 
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/

#include <threads.h>

#define CPPHTTPLIB_OPENSSL_SUPPORT
#include "httplib.h"

#include "memops.hpp"
#include "strops.hpp"
#include "logger.hpp"
#include "importer.hpp"

static bool _openAI_batch_query_with_file(char** queries, size_t query_count, char* file_id, invoice* buffer, importer::batch_query_response_handler response_handler)
{
    const char *api_key = administration::get_ai_service().api_key_public;
    httplib::SSLClient cli("api.openai.com", 443);

    thrd_t threads[20];

    for (u32 i = 0; i < query_count; i++)
    {       
        auto* func = new auto([&api_key, &cli, i, &file_id, &response_handler, &buffer, &queries]() {
            char* query_escaped = strops::prep_str_for_json(queries[i], 1000);

            size_t body_size = 1000; // Ballpark
            char* body = (char*)memops::alloc(body_size);
            strops::format(body, body_size, 
                "{ \"model\":\"%s\", "
                "  \"input\": [ "
                "  { \"role\": \"user\", "
                "    \"content\": [ "
                "    { \"type\": \"input_file\", \"file_id\": \"%s\" }, "
                "    { \"type\": \"input_text\", \"text\": \"%s\" } "
                "  ] "
                "  }"
                "], "
                " \"text\":  { \"format\": { \"type\": \"json_object\" } } "
                "}", administration::get_ai_service().model_name, file_id, query_escaped);

            httplib::Headers headers;
            headers.insert(std::make_pair("Authorization", std::string("Bearer ") + api_key));

            httplib::Result res = cli.Post("/v1/responses", headers, body, "application/json");
            memops::unalloc(body);

            if (!res || res->status != 200) {
                logger::error("ERROR Failed to query API.");
                logger::error(res->body.c_str());
                return 0;
            }

            char* response_body = (char*)res->body.c_str();
            char* response = (char*)memops::alloc(5000);
            memops::zero(response, 5000);
            strops::copy(response, response_body, 5000);
            
            strops::get_json_value(response, "text", response, 5000);
            strops::unprep_str_from_json(response);

            response_handler(buffer, response);
            
            memops::unalloc(response);
            memops::unalloc(query_escaped);
            return 1;
        });

        auto trampoline = [](void* arg) -> int {
            auto* f = static_cast<decltype(func)>(arg);
            (*f)();
            delete f;
            return 0;
        };
        
        thrd_create(&threads[i], trampoline, func);
    }

    for (u32 i = 0; i < query_count; i++) thrd_join(threads[i], nullptr);

    return 1;
}

static bool _openAI_query_with_file(char* query, size_t query_length, char* file_id, char** response)
{
    const char *api_key = administration::get_ai_service().api_key_public;
    
    httplib::SSLClient cli("api.openai.com", 443);
    //cli.enable_server_certificate_verification(false);

    char* query_escaped = strops::prep_str_for_json(query, query_length);
    memops::unalloc(query);
    
    size_t body_size = query_length + 200;
    char* body = (char*)memops::alloc(body_size);
    strops::format(body, body_size, 
        "{\"model\":\"%s\", \"input\": [ { \"role\": \"user\", \"content\": [ { \"type\": \"input_file\", \"file_id\": \"%s\" }, "
        "{ \"type\": \"input_text\", \"text\": \"%s\" } ] } ] }", administration::get_ai_service().model_name, file_id, query_escaped);

    httplib::Headers headers;
    headers.insert(std::make_pair("Authorization", std::string("Bearer ") + api_key));

    httplib::Result res = cli.Post("/v1/responses", headers, body, "application/json");
    memops::unalloc(body);

    if (!res || res->status != 200) {
        logger::error("ERROR Failed to query API.");
        logger::error(res->body.c_str());
        return 0;
    }

    char* response_body = (char*)res->body.c_str();
    *response = (char*)memops::alloc(100000);
    memops::zero(*response, 100000);
    strops::copy(*response, response_body, 100000);
    
    strops::get_json_value(*response, "text", *response, 100000);
    *response = strops::unprep_str_from_json(*response);

    return 1;
}

static bool _openAI_upload_file(char* file_path, char* file_id, size_t file_id_len)
{
    const char *api_key = administration::get_ai_service().api_key_public;
    const char *filename = strops::get_filename(file_path);

    FILE* orig_file = fopen(file_path, "rb");
    if (orig_file == NULL) {
        logger::error("ERROR: file to upload could not be opened.");
        return 0;
    }

    fseek(orig_file, 0L, SEEK_END);
    long sz = ftell(orig_file);
    fseek(orig_file, 0, SEEK_SET);
    
    httplib::SSLClient cli("api.openai.com", 443);
    //cli.enable_server_certificate_verification(false);
    
    char body[512];
    strops::format(body, sizeof(body), "{\"filename\":\"%s\",\"purpose\":\"user_data\", \"bytes\": %d, \"mime_type\": \"application/pdf\", \"expires_after\": { \"anchor\": \"created_at\", \"seconds\": 3600 } }", filename, sz);

    httplib::Headers headers;
    headers.insert(std::make_pair("Authorization", std::string("Bearer ") + api_key));

    httplib::Result res = cli.Post("/v1/uploads", headers, body, "application/json");
    if (!res || res->status != 200) {
        logger::error("ERROR Failed to create upload.");
        logger::error(res->body.c_str());
        fclose(orig_file);
        return 0;
    }

    char upload_id[128];
    strops::get_json_value(res->body.c_str(), "id", upload_id, sizeof(upload_id));
    size_t part_size = 64000000; // 64mb
    logger::info("Created upload %s with part size %zu.", upload_id, part_size);

    char *buffer = (char*)memops::alloc(part_size);

    char completion_body[1048];
    strops::format(completion_body, sizeof(completion_body), "{\"part_ids\": [");

    int part_number = 0;
    while (1) {
        size_t read_bytes = fread(buffer, 1, part_size, orig_file);
        if (read_bytes == 0) break;

        httplib::Headers part_headers;
        part_headers.insert(std::make_pair("Authorization", std::string("Bearer ") + api_key));

        std::string chunk(buffer, read_bytes);

        httplib::UploadFormDataItems items = {
            {"data", chunk, filename, "application/octet-stream"}
        };

        char path[256];
        strops::format(path, sizeof(path), "/v1/uploads/%s/parts?part_number=%d", upload_id, part_number);

        httplib::Result part_res = cli.Post(path, part_headers, items);

        if (!part_res || part_res->status != 200) {
            logger::error("Failed to upload part %d.", part_number);
            logger::error(part_res->body.c_str());
            memops::unalloc(buffer);
            fclose(orig_file);
            return 0;
        }
        else {
            char part_id[128];
            strops::get_json_value(part_res->body.c_str(), "id", part_id, sizeof(part_id));
            if (part_number == 0) strops::format(completion_body+strops::length(completion_body), sizeof(completion_body)-strops::length(completion_body), "\"%s\"", part_id);
            if (part_number != 0) strops::format(completion_body+strops::length(completion_body), sizeof(completion_body)-strops::length(completion_body), ", \"%s\"", part_id);
        }

        logger::info("Uploaded part %d\n", part_number);
        part_number++;
    }

    strops::format(completion_body+strops::length(completion_body), sizeof(completion_body)-strops::length(completion_body), "]}");

    memops::unalloc(buffer);
    fclose(orig_file);

     // ---------- Step 3: Complete upload ----------

    httplib::Result complete_res = cli.Post((std::string("/v1/uploads/") + upload_id + "/complete").c_str(),
                                            headers, completion_body, "application/json");


    if (!complete_res || complete_res->status != 200) {
        logger::error("ERROR Failed to complete upload.");
        logger::error(complete_res->body.c_str());
        return 0;
    }

    char* completion_body_response = (char*)complete_res->body.c_str();
    strops::get_json_value(completion_body_response, "id", file_id, file_id_len, 1);

    return 1;
}

static bool _openAI_get_available_models(importer::model_list_request* buffer) 
{
    const char *api_key = administration::get_ai_service().api_key_public;

    httplib::SSLClient cli("api.openai.com", 443);

    httplib::Headers headers;
    headers.insert(std::make_pair("Authorization", std::string("Bearer ") + api_key));

    httplib::Result res = cli.Get("/v1/models", headers);
    if (!res || res->status != 200) {
        logger::error("ERROR Failed to get models list.");
        logger::error(res->body.c_str());
        return 0;
    }

    char* completion_body_response = (char*)res->body.c_str();

    u32 count = 0;
    char model_name[MAX_LEN_SHORT_DESC];

    while(1) {
        if (!strops::get_json_value(completion_body_response, "id", model_name, MAX_LEN_SHORT_DESC, count++)) break;
        if (count == MAX_MODEL_LIST_RESULT_COUNT) break;

        strops::copy(buffer->result[buffer->result_count++], model_name, MAX_LEN_SHORT_DESC);
    }

    return 1;
}

importer::ai_provider_impl _chatgpt_api_provider = {
    "OpenAI",
    "gpt-5-nano",
    _openAI_upload_file,
    _openAI_query_with_file,
    _openAI_batch_query_with_file,
    _openAI_get_available_models,
};