#include <errno.h>
#include <stdint.h>
#include <stdio.h>

#include "error.h"
#include "file.h"
#include "flac.h"
#include "m4a.h"
#include "mp3.h"
#include "opus.h"
#include "vorbis.h"
#include "wav.h"
#include "sid.h"

/**
 * Obtain file type string from file_types enum.
 *
 * \param	ft	File type enum.
 * \return		String representation of enum.
 */
const char* fileToStr(enum file_types ft)
{
	static const char *file_types_str[] = {
		"UNKNOWN",
		"WAV",
		"FLAC",
		"VORBIS",
		"OPUS",
		"MP3",
		"SID",
		"M4A",
		"AAC"
	};

	return file_types_str[ft];
}

/**
 * Obtains file type.
 *
 * \param	file	File location.
 * \return			file_types enum or 0 on error and errno set.
 */
enum file_types getFileType(const char *file)
{
	FILE* ftest = fopen(file, "rb");
	uint32_t fileSig;
	enum file_types file_type = FILE_TYPE_ERROR;

	/* Failure opening file */
	if(ftest == NULL)
		return FILE_TYPE_ERROR;

	if(fread(&fileSig, 4, 1, ftest) == 0)
		goto err;

	switch(fileSig)
	{
		// "RIFF"
		case 0x46464952:
		// "riff"
		case 0x66666972:
		// "RIFX"
		case 0x58464952:
		// "RF64"
		case 0x34364652:
		// "FORM"
		case 0x4D524F46:
			file_type = FILE_TYPE_WAV;
			break;

		// "fLaC"
		case 0x43614c66:
			file_type = FILE_TYPE_FLAC;
			break;

		// "OggS"
		case 0x5367674F:
			if(isOpus(file) == 0)
				file_type = FILE_TYPE_OPUS;
			else if(isFlac(file) == 0)
				file_type = FILE_TYPE_FLAC;
			else if(isVorbis(file) == 0)
				file_type = FILE_TYPE_VORBIS;
			else
				errno = FILE_NOT_SUPPORTED;

			break;
		
		// "PSID" or "RSID"
		case 0x44495350:
		case 0x44495352:
			file_type = FILE_TYPE_SID;
			break;

	default:
		/* Check for M4A/AAC/ALAC (MP4 container with ftyp atom) */
		if((fileSig == 0x70797466) || /* 'ftyp' at offset 4 */
		   (fileSig == 0x65657266))    /* 'free' at offset 4 (some M4A files) */
		{
			file_type = FILE_TYPE_M4A;
			break;
		}
		
		/* Check for raw AAC (ADTS format) - sync word 0xFFF */
		if((fileSig & 0xFFF60000) == 0xFFF00000)
		{
			file_type = FILE_TYPE_AAC;
			break;
		}

		/*
		 * MP3 without ID3 tag, ID3v1 tag is at the end of file, or MP3
		 * with ID3 tag at the beginning  of the file.
		 */
		if(isMp3(file) == 0)
		{
			file_type = FILE_TYPE_MP3;
			break;
		}

		/* TODO: Add this again at some point */
		//printf("Unknown magic number: %#010x\n.", fileSig);
		errno = FILE_NOT_SUPPORTED;
		break;
	}err:
	fclose(ftest);
	return file_type;
}