#include "unicode.hpp"

using namespace unicode;

string::string() {

    m_code=std::make_pair(0,0);
    m_range=std::make_pair(0,0);
    
};/*string*/

string::~string() throw() {
    
};/*~string*/

string&
string::decode(
    std::vector<unsigned char>& data
) {

    while(!data.empty()) {
        if(m_code.first--==0) {
            if(m_range.second>0) {
                if(m_code.second>=m_range.first &&
                        m_code.second<=m_range.second) {
                    push_back(m_code.second);
                }else{
                    throw;/*overlong form*/
                }
            }
            if(*data.begin()>=0x00 && *data.begin()<=0x7F) {
                /*ASCII*/
                m_code.first=0;
                m_code.second=*data.begin();
                m_range=std::make_pair(0x00,0x7F);
            }else{
                if(*data.begin()>=0xC2 && *data.begin()<=0xDF) {
                    /*2-byte sequence*/
                    m_code.first=1;
                    m_code.second=*data.begin() & 0x1F;
                    m_range=std::make_pair(0xFF,0x7FF);
                }else if(*data.begin()>=0xE0 && *data.begin()<=0xEF) {
                    /*3-byte sequence*/
                    m_code.first=2;
                    m_code.second=*data.begin() & 0x0F;
                    m_range=std::make_pair(0x800,0xFFFF);
                }else if(*data.begin()>=0xF0 && *data.begin()<=0xF4) {
                    /*4-byte sequence*/
                    m_code.first=3;
                    m_code.second=*data.begin() & 0x07;
                    m_range=std::make_pair(0x10000,0x10FFFF);
                }else{
                    /*invalid UTF-8 sequence*/
                    throw;
                }
            }
        }else if(*data.begin()>=0x80 && *data.begin()<=0xBF) {
            /*multi-byte sequence*/
            m_code.second<<=6;
            m_code.second+=*data.begin() & 0x3F;
        }else{
            /*invalid UTF-8 sequence*/
            throw;
        }
        data.erase(data.begin());
    }
    /*check if last byte is in decoded state*/
    if(m_code.first==0) {
        if(m_code.second>=m_range.first &&
                m_code.second<=m_range.second) {
            push_back(m_code.second);
        }else{
            throw;/*overlong form*/
        }
        m_code=std::make_pair(0,0);
        m_range=std::make_pair(0,0);
    }
    return *this;
    
};/*decode*/

std::vector<unsigned char>
string::encode() {

};/*encode*/