#include "utils/utils.h"
#include <email_parser/emailparser.h>

#include <utils/utils.h>
#include <check/check.h>
#include <boost/regex.hpp>
#include <sstream>
#include <iostream>
#include <bits/stdc++.h>
#include <fstream>
#if __GNUC__ < 8 && __clang_major__ < 17
#	include <experimental/filesystem>
    using namespace std::experimental::filesystem;
#else
#	include <filesystem>
    using namespace std::filesystem;
#endif

std::string EmailParser::get_payload_in_email(std::string &email_content) {
    boost::regex content_type_and_transfer_encoding_regex("Content-Type");
    // boost::regex body_start_regex("\r\n\r\n"); //boost::regex_constants::egrep
    // boost::smatch smatch;
    // if (boost::regex_search(email_content, smatch, body_start_regex)) {
    //     return email_content.substr(smatch.position(), email_content.length());
    // }
    // return "";
}

std::multimap<std::string, std::string> EmailParser::parse_email_content_types(std::string path) {
    std::ifstream input_file(path, std::ios::in);

    std::string line = "";
    std::multimap<std::string, std::string> mail_options;
    std::string latest_key;
    while(std::getline(input_file, line)) {
        // ;

        char first_char = line.substr(0, 1)[0];
        // if (line == "\0") {
            // break;
        // }

        std::vector<std::string> split_by_colon = split(line, ":");
        std::string key = split_by_colon[0];
        std::string value = "";

        for (int i = 1; i < split_by_colon.size(); i ++)  value += split_by_colon[i];
        if (key != "Content-Type" ) {
            continue;
        }

        if (first_char == '\t') {
            mail_options.emplace(std::make_pair(latest_key, line));
        } else {
            // std::cout << "key: " << key << "\nvalue: " << value << std::endl;
            mail_options.emplace(std::make_pair(key, value));
            latest_key = key;
        }
    }
    return mail_options;
}

// std::vector<int> EmailParser::find_base64_blocks_in_email(std::string &email_content) {
//     std::string glued_together;
//     for (auto c : email_content) {
//         if (c == '\n') continue;
//         glued_together.push_back(c);
//     }
//     boost::regex base64_regex("^[-A-Za-z0-9+/]*={0,3}$");
// }



EmailParser::EmailParser() {

}

std::vector<int> search_content_types_in_email_content(std::string& email_content) {
    std::vector<int> content_type_positions = {};
    boost::regex image_content_type_regex("Content-Type: image/.*");
    for (boost::sregex_iterator it{email_content.begin(), email_content.end(), image_content_type_regex}, end{};
         it != end; it++) {
        content_type_positions.push_back(it->position());
    }
    return content_type_positions;
}

// void find_and_decode_email_content()

Check EmailParser::parse(std::string &email_content) {
    //1. Search "Content-Type: image/.*" in the .eml file.
    //  1.1 If found 0, go to [2]
    //  1.2 If found 1, try decoding it, if it's not a QR code, go to [2]
    //  1.3 Loop through every found entry. If not found in any, go to [2]
    //2. Try decoding content of the e-mail
    //3. Search "t=\d{8}T\d{4,6}&s=\d{1,6}\.\d{1,2}&fn=\d{10,16}&i=\d{6}&fp=\d{10}&n=\d". Note that in some emails = and & signs could be replaced with its code in HTTP requests: %3D, %26
    // 3.1 If not found, notify the user that we could not parse the .eml file
    std::vector<int> content_type_positions = search_content_types_in_email_content(email_content);

    if (content_type_positions.size() < 0) {

    } else if (content_type_positions.size() == 1) {

    } else {

    }

    // std::string payload = get_payload_in_email(email_content);
    // Check c;

    // std::cout << payload << std::endl;

    // if (payload == "")
    //     return c;



    // return c;
}

Check EmailParser::parse_file(std::string path) {

    // std::vector<std::string> contents = read_file(path);
    // unsigned int body_start = -1;
    // for (unsigned int i = 0; i < contents.size(); i ++) {
    //     std::string &line = contents[i];
    //     if (line == "\r") {
    //         body_start = i;
    //         break;
    //     }
    // }
    // if (body_start == (unsigned int) -1) throw "Not an E-Mail";

    // for (unsigned int i = 0; i < contents.size(); i ++) {
    //     std::string &line = contents[i];
    //     if (line[0] == '\t') {
    //         contents[i - 1] += " " + contents[i];
    //         contents.erase(remove(contents.begin(), contents.end(), line), contents.end());
    //         i -= 2;
    //     }
    // }

    // for (auto &line : contents) {
    //     std::cout << line << std::endl;
    // }

    // std::cout << contents[body_start + 1] << std::endl;
    // unsigned int body_start = contents.find("\r\n\r\n");
    // if (body_start == (unsigned int)-1)
        // throw "Not a E-Mail file";
    // std::cout << contents.erase(0, body_start + 4);
    // std::cout << contents << std::endl;

    // std::vector<std::tuple<int, int>> message_parts_positions;

    // while (contents.find("--") > 0) {

    // }

    return Check();

    std::multimap<std::string, std::string> content_types = parse_email_content_types(path);
    bool found_qr_image = false;
    for (auto &content_type : content_types) {
        boost::regex image_content_type_regex("image\\/(png|gif|jpg|jpeg)");
        boost::cmatch cmatch;
        if (boost::regex_match(content_type.second.c_str(), cmatch, image_content_type_regex)) {
            std::cout << cmatch << std::endl;
            
        }
        std::cout << content_type.first << ": " << content_type.second << std::endl;
    }

    // std::ifstream ifile(path, std::ios::in | std::ios::binary);
    // const unsigned int size = std::filesystem::file_size(path);
    // std::string content(size, '\0');
    // ifile.read(content.data(), size);
    // return parse(content);
    return Check();
}