// Copyright 2008 Dolphin Emulator Project
// Licensed under GPLv2+
// Refer to the license.txt file included.

#include <string>

#include "AudioCommon/WaveFile.h"
#include "Common/CommonTypes.h"
#include "Core/ConfigManager.h"

enum { BUF_SIZE = 32*1024 };

WaveFileWriter::WaveFileWriter():
	skip_silence(false),
	audio_size(0),
	conv_buffer(nullptr)
{
}

WaveFileWriter::~WaveFileWriter()
{
	delete[] conv_buffer;
	Stop();
}

bool WaveFileWriter::Start(const std::string& filename, unsigned int HLESampleRate)
{
	if (!conv_buffer)
		conv_buffer = new short[BUF_SIZE];

	// Check if the file is already open
	if (file)
	{
		PanicAlertT("The file %s was already open, the file header will not be written.", filename.c_str());
		return false;
	}

	file.Open(filename, "wb");
	if (!file)
	{
		PanicAlertT("The file %s could not be opened for writing. Please check if it's already opened by another program.", filename.c_str());
		return false;
	}

	audio_size = 0;

	// -----------------
	// Write file header
	// -----------------
	Write4("RIFF");
	Write(100 * 1000 * 1000);  // write big value in case the file gets truncated
	Write4("WAVE");
	Write4("fmt ");

	Write(16);  // size of fmt block
	Write(0x00020001); //two channels, uncompressed

	const u32 sample_rate = HLESampleRate;
	Write(sample_rate);
	Write(sample_rate * 2 * 2); //two channels, 16bit

	Write(0x00100004);
	Write4("data");
	Write(100 * 1000 * 1000 - 32);

	// We are now at offset 44
	if (file.Tell() != 44)
		PanicAlert("Wrong offset: %lld", (long long)file.Tell());

	return true;
}

void WaveFileWriter::Stop()
{
	// u32 file_size = (u32)ftello(file);
	file.Seek(4, SEEK_SET);
	Write(audio_size + 36);

	file.Seek(40, SEEK_SET);
	Write(audio_size);

	file.Close();
}

void WaveFileWriter::Write(u32 value)
{
	file.WriteArray(&value, 1);
}

void WaveFileWriter::Write4(const char *ptr)
{
	file.WriteBytes(ptr, 4);
}

void WaveFileWriter::AddStereoSamples(const short *sample_data, u32 count)
{
	if (!file)
		PanicAlertT("WaveFileWriter - file not open.");

	if (skip_silence)
	{
		bool all_zero = true;

		for (u32 i = 0; i < count * 2; i++)
		{
			if (sample_data[i])
				all_zero = false;
		}

		if (all_zero)
			return;
	}

	file.WriteBytes(sample_data, count * 4);
	audio_size += count * 4;
}

void WaveFileWriter::AddStereoSamplesBE(const short *sample_data, u32 count)
{
	if (!file)
		PanicAlertT("WaveFileWriter - file not open.");

	if (count > BUF_SIZE * 2)
		PanicAlert("WaveFileWriter - buffer too small (count = %u).", count);

	if (skip_silence)
	{
		bool all_zero = true;

		for (u32 i = 0; i < count * 2; i++)
		{
			if (sample_data[i])
				all_zero = false;
		}

		if (all_zero)
			return;
	}

	for (u32 i = 0; i < count; i++)
	{
		//Flip the audio channels from RL to LR
		conv_buffer[2 * i] = Common::swap16((u16)sample_data[2 * i + 1]);
		conv_buffer[2 * i + 1] = Common::swap16((u16)sample_data[2 * i]);
	}

	file.WriteBytes(conv_buffer, count * 4);
	audio_size += count * 4;
}