#include <sys/param.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "ft_printf_internal.h"

int expandBuffer(struct printf_data* data, int size)
{
    if (!data->realloc)
        return -1;
    int finalSize = ((size / PRINTF_OUTPUT_BUFFER_INCREMENT) +1) * PRINTF_OUTPUT_BUFFER_INCREMENT;
    char* newBuffer = (char*) malloc(sizeof(*newBuffer) * finalSize);
    if (!newBuffer)
        return -1;
    if (data->outputBuffer)
    {
        memcpy(newBuffer, data->outputBuffer, data->bufferMaxSize);
        free(data->outputBuffer);
    }
    data->outputBuffer = newBuffer;
    data->bufferMaxSize = finalSize;
    return 0;
}

int appendToBuffer(struct printf_data* data, const char* buf, size_t len)
{
    int sizeToWrite = MIN(len, data->bufferMaxSize - data->written);
    int totalWritten = data->written;

    if (!data->outputBuffer && !data->realloc)
        return -1;
    if (data->outputBuffer)
    {
        memcpy(&data->outputBuffer[data->written], buf, sizeToWrite);
        data->written += sizeToWrite;
        len -= sizeToWrite;
        buf += sizeToWrite;
    }
    if (len > 0)
    {
        if (expandBuffer(data, data->bufferMaxSize + len) == -1)
            return -1;
        sizeToWrite = MIN(len, data->bufferMaxSize - data->written);
        memcpy(&data->outputBuffer[data->written], buf, sizeToWrite);
        data->written += sizeToWrite;
    }
    return data->written - totalWritten;
}

void flushBuffer(struct printf_data* data)
{
    if (data->outputBuffer)
    {
        appendToBuffer(data, "", 1);
        if (data->realloc && data->written != data->bufferMaxSize)
        {
            char* newBuf = (char*) malloc(sizeof(*newBuf) * data->written);
            memcpy(newBuf, data->outputBuffer, data->written);
            free(data->outputBuffer);
            data->outputBuffer = newBuf;
        }
    }
    if (data->fdBuffer && data->bufferPos)
    {
        write(data->fd, data->fdBuffer, data->bufferPos);
    }
}

int printfWrite(struct printf_data* data, const char* buf, size_t len)
{
    if (data->outputBuffer || data->realloc)
        return appendToBuffer(data, buf, len);
    if (data->fdBuffer)
    {
        int totalLen = len;
        while (len > 0)
        {
            int result = appendToFdBuffer(data, buf, len);
            if (result < 0)
                return result;
            len -= result;
        }
        data->written += totalLen;
        return totalLen;
    }
    int written = write(data->fd, buf, len);
    data->written += written;
    return written;
}