#include <rez/file.h>
#include <rez/entry.h>
#include <rez/resource.h>
#include <cstddef>
#include <iostream>

std::string rez::file::path() const
{
    return resource.name();
}

long rez::file::tell()
{
    return offset;
}

int rez::file::seek(long offset)
{
    if (offset < 0 || offset > resource.entry.size)
        return -1;
    else if (io.seek(resource.entry.pos + offset))
        return -1;

    this->offset = offset;
    return 0;
}

int rez::file::eof() const
{
    return offset >= resource.entry.size;
}

int rez::file::read(void *b, size_t n)
{
    const rez::entry &entry = resource.entry;
    unsigned long roffset = offset + entry.pos,
        end = entry.pos + entry.size, remaining = end - roffset;

    if (n > remaining)
    {
        std::cerr << path() << ": requested " << n << " bytes, only "
            << remaining << " remaining" << std::endl;
        return -1;
    }

    if (seek(offset) || io.read(b, n))
        return -1;

    offset += n;
    return 0;
}

int rez::file::read(unsigned char &b)
{
    return read(&b, sizeof b);
}

int rez::file::read(std::string &s, size_t len)
{
    for (size_t i = 0; i < len; i++)
    {
        char b;

        if (read(&b, sizeof b))
            return -1;

        s += b;
    }

    return 0;
}

int rez::file::read_le(uint16_t &w)
{
    unsigned char b[sizeof w];

    if (read(b, sizeof b))
        return -1;

    w = b[0] | (b[1] << 8);
    return 0;
}

int rez::file::read_le(uint32_t &w)
{
    unsigned char b[sizeof w];

    if (read(b, sizeof b))
        return -1;

    w = b[0] | (b[1] << 8u) | (b[2] << 16u) | (b[3] << 24u);
    return 0;
}

rez::file::file(const rez::resource &resource, rez::io &io) :
    resource(resource),
    offset(0),
    io(io)
{
}