#include "FileLoader.h"
#include "FileReader.h"
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <stdint.h>

/** Create a FileLoader. */
FileLoader::FileLoader()
{
    m_buf = NULL;
    m_line_endings = LINE_ENDING_LF;
    m_lines = NULL;
}

FileLoader::~FileLoader()
{
    if (m_buf != NULL)
    {
        delete[] m_buf;
        m_buf = NULL;
    }
}

bool FileLoader::load(const char * fname)
{
    size_t size;

    if (!FileReader::load(fname, &m_buf, &size))
    {
        return false;
    }

    load_buf(size);

    return true;
}

void FileLoader::load_buf(size_t size)
{
    LineIndexPairVectorRef lines[LINE_ENDING_COUNT];
    size_t line_start[LINE_ENDING_COUNT] = {0};
    unsigned int n_cr = 0;
    unsigned int n_lf = 0;
    bool crlf = true;
    for (size_t i = 0; i < LINE_ENDING_COUNT; i++)
    {
        lines[i] = std::make_shared<LineIndexPairVector>();
    }
    for (size_t i = 0; i < size; i++)
    {
        if (m_buf[i] == '\r')
        {
            lines[LINE_ENDING_CR]->push_back(LineIndexPair(&m_buf[line_start[LINE_ENDING_CR]], i - line_start[LINE_ENDING_CR]));
            n_cr++;
            line_start[LINE_ENDING_CR] = i + 1;
            if (crlf)
            {
                if ((i < (size - 1)) && (m_buf[i + 1] == '\n'))
                {
                    lines[LINE_ENDING_CRLF]->push_back(LineIndexPair(&m_buf[line_start[LINE_ENDING_CRLF]], i - line_start[LINE_ENDING_CRLF]));
                    n_lf++;
                    i++;
                    line_start[LINE_ENDING_CRLF] = i + 1;
                }
                else
                {
                    crlf = false;
                }
            }
        }
        else if (m_buf[i] == '\n')
        {
            lines[LINE_ENDING_LF]->push_back(LineIndexPair(&m_buf[line_start[LINE_ENDING_LF]], i - line_start[LINE_ENDING_LF]));
            crlf = false;
            n_lf++;
            line_start[LINE_ENDING_LF] = i + 1;
        }
    }

    if (crlf && (n_lf > 0u))
    {
        m_line_endings = LINE_ENDING_CRLF;
        m_lines = lines[LINE_ENDING_CRLF];
    }
    else if ((n_cr > 0u) && (n_lf == 0u))
    {
        m_line_endings = LINE_ENDING_CR;
        m_lines = lines[LINE_ENDING_CR];
    }
    else
    {
        m_line_endings = LINE_ENDING_LF;
        m_lines = lines[LINE_ENDING_LF];
    }
}