/*////////////////////////////////////////////////////////////////////////////////////////

fsop contains coomprensive set of function for file and folder handling

en exposed s_fsop fsop structure can be used by callback to update operation status

////////////////////////////////////////////////////////////////////////////////////////*/

#include <stdio.h>
#include <stdarg.h>
#include <string.h>
#include <math.h>
#include <ogcsys.h>
#include <ogc/lwp_watchdog.h>

#include <dirent.h>
#include <unistd.h>
#include <sys/statvfs.h>

#include "fileOps.h"
#include "memory/mem2.hpp"
#include "utils.h"
#include "gecko.h"

#define SET(a, b) a = b; DCFlushRange(&a, sizeof(a));
#define STACKSIZE 8192

static u8 *buff = NULL;
static FILE *fs = NULL, *ft = NULL;
static u32 bytes;
static u32 block = 32768;
static u32 blockIdx = 0;
static u32 blockInfo[2] = {0,0};
static u32 blockReady = 0;
static s32 stopThread;
static u64 folderSize = 0;

// return false if the file doesn't exist
bool fsop_GetFileSizeBytes (char *path, size_t *filesize)	// for me stats st_size report always 0 :(
{
	FILE *f;
	size_t size = 0;

	f = fopen(path, "rb");
	if (!f)
	{
		if (filesize) *filesize = size;
		return false;
	}

	//Get file size
	fseek( f, 0, SEEK_END);
	size = ftell(f);
	if (filesize) *filesize = size;
	SAFE_CLOSE(f);
	
	return true;
}

/*
Recursive fsop_GetFolderBytes
*/
u64 fsop_GetFolderBytes (char *source)
{
	DIR *pdir;
	struct dirent *pent;
	char newSource[300];
	u64 bytes = 0;

	pdir = opendir(source);

	while ((pent=readdir(pdir)) != NULL) 
	{
		// Skip it
		if (strcmp (pent->d_name, ".") == 0 || strcmp (pent->d_name, "..") == 0)
			continue;

		snprintf(newSource, sizeof(newSource), "%s/%s", source, pent->d_name);

		// If it is a folder... recurse...
		if (fsop_DirExist (newSource))
		{
			bytes += fsop_GetFolderBytes (newSource);
		}
		else	// It is a file !
		{
			size_t s;
			fsop_GetFileSizeBytes (newSource, &s);
			bytes += s;
		}
	}
	closedir(pdir);

	return bytes;
}

u32 fsop_GetFolderKb (char *source)
{
	u32 ret = (u32) round ((double)fsop_GetFolderBytes (source) / 1000.0);

	return ret;
}

u32 fsop_GetFreeSpaceKb (char *path) // Return free kb on the device passed
{
	struct statvfs s;

	statvfs(path, &s);

	u32 ret = (u32)round( ((double)s.f_bfree / 1000.0) * s.f_bsize);

	return ret ;
}

bool fsop_FileExist(const char *fn)
{
	FILE * f;
	f = fopen(fn, "rb");
	if (f) 
	{
		fclose(f);
		return true;
	}
	return false;
}

bool fsop_DirExist (char *path)
{
	DIR *dir;

	dir=opendir(path);
	if (dir)
	{
		closedir(dir);
		return true;
	}

	return false;
}

static void *thread_CopyFileReader()
{
	u32 rb;
	stopThread = 0;
	DCFlushRange(&stopThread, sizeof(stopThread));
	do
	{
		SET (rb, fread(&buff[blockIdx*block], 1, block, fs ));
		SET (blockInfo[blockIdx], rb);
		SET (blockReady, 1);

		while (blockReady && !stopThread) usleep(1);
	}
	while (stopThread == 0);

	stopThread = -1;
	DCFlushRange(&stopThread, sizeof(stopThread));

	return 0;
}

bool fsop_CopyFile (char *source, char *target, progress_callback_t spinner, void *spinner_data)
{
	gprintf("Creating file: %s\n",target);
	int err = 0;

	u32 size;
	u32 rb,wb;

	fs = fopen(source, "rb");
	if (!fs)
	{
		return false;
	}

	ft = fopen(target, "wt");
	if (!ft)
	{
		SAFE_CLOSE(fs);
		return false;
	}

	//Get file size
	fseek (fs, 0, SEEK_END);
	size = ftell(fs);

	if (size == 0)
	{
		SAFE_CLOSE(fs);
		SAFE_CLOSE(ft);
		return true;
	}

	// Return to beginning....
	fseek(fs, 0, SEEK_SET);

	u8 * threadStack = NULL;
	lwp_t hthread = LWP_THREAD_NULL;

	buff = MEM2_alloc(block*2);

	blockIdx = 0;
	blockReady = 0;
	blockInfo[0] = 0;
	blockInfo[1] = 0;

	threadStack = MEM2_alloc(STACKSIZE);
	LWP_CreateThread (&hthread, thread_CopyFileReader, NULL, threadStack, STACKSIZE, 30);

	while (stopThread != 0)
		usleep (5);

	u32 bi;
	do
	{
		while (!blockReady) usleep (1); // Let's wait for incoming block from the thread
		
		bi = blockIdx;

		// let's th thread to read the next buff
		SET (blockIdx, 1 - blockIdx);
		SET (blockReady, 0);

		rb = blockInfo[bi];
		// write current block
		wb = fwrite(&buff[bi*block], 1, rb, ft);

		if (wb != wb) err = 1;
		if (rb == 0) err = 1;
		bytes += rb;

		if (spinner)
			spinner(bytes, folderSize, spinner_data);
	}
	while (bytes < size && err == 0);

	stopThread = 1;
	DCFlushRange(&stopThread, sizeof(stopThread));

	while (stopThread != -1)
		usleep (5);

	LWP_JoinThread(hthread, NULL);
	MEM2_free(threadStack);

	stopThread = 1;
	DCFlushRange(&stopThread, sizeof(stopThread));

	SAFE_CLOSE(fs);
	SAFE_CLOSE(ft);
	MEM2_free(buff);

	if (err) 
	{
		unlink (target);
		return false;
	}

	return true;
}

/*
Recursive copyfolder
*/
static bool doCopyFolder (char *source, char *target, progress_callback_t spinner, void *spinner_data)
{
	DIR *pdir;
	struct dirent *pent;
	char newSource[300], newTarget[300];
	bool ret = true;

	// If target folder doesn't exist, create it !
	if (!fsop_DirExist(target))
	{
		gprintf("Creating directory: %s\n",target);
		makedir(target);
	}

	pdir = opendir(source);

	while ((pent=readdir(pdir)) != NULL && ret == true) 
	{
		// Skip it
		if (strcmp (pent->d_name, ".") == 0 || strcmp (pent->d_name, "..") == 0)
			continue;
	
		snprintf(newSource, sizeof(newSource), "%s/%s", source, pent->d_name);
		snprintf(newTarget, sizeof(newTarget), "%s/%s", target, pent->d_name);
		
		// If it is a folder... recurse...
		if (fsop_DirExist(newSource))
		{
			ret = doCopyFolder(newSource, newTarget, spinner, spinner_data);
		}
		else	// It is a file !
		{
			ret = fsop_CopyFile(newSource, newTarget, spinner, spinner_data);
		}
	}

	closedir(pdir);

	return ret;
}

bool fsop_CopyFolder (char *source, char *target, progress_callback_t spinner, void *spinner_data)
{
	gprintf("DML game USB->SD job started!\n");

	bytes = 0;
	folderSize = fsop_GetFolderBytes(source);
	return doCopyFolder(source, target, spinner, spinner_data);
}

void fsop_deleteFolder(char *source)
{
	DIR *pdir;
	struct dirent *pent;
	char newSource[300];

	pdir = opendir(source);

	while ((pent=readdir(pdir)) != NULL) 
	{
		// Skip it
		if (strcmp (pent->d_name, ".") == 0 || strcmp (pent->d_name, "..") == 0)
			continue;

		snprintf (newSource, sizeof(newSource), "%s/%s", source, pent->d_name);

		// If it is a folder... recurse...
		if (fsop_DirExist(newSource))
		{
			fsop_deleteFolder(newSource);
		}
		else	// It is a file !
		{
			gprintf("Deleting file: %s\n",newSource);
			remove(newSource);
		}
	}
	closedir(pdir);
	gprintf("Deleting directory: %s\n",source);
	unlink(source);
}