#include <iostream>
#include <sys/stat.h>
#include <sys/types.h>

#include "util.h"
#include "configfsisomanager.h"
#include <dirent.h>
#include <unistd.h>
#include <string.h>

bool supported()
{
	return fs_mount_point((char*)"configfs") != nullptr;
}

char *get_gadget_root()
{
	char *configFsRoot = fs_mount_point((char*)"configfs");
	char *usbGadgetRoot = strjin(configFsRoot, (char*)"/usb_gadget/"); 
	char *gadgetRoot = nullptr;

	struct dirent *entry = nullptr;
	DIR *dp = nullptr;
	dp = opendir(usbGadgetRoot);
	if (dp != nullptr)
		while ((entry = readdir(dp)))
		{
			if (entry->d_name[0] != '.')
			{
				char *gadget = strjin(usbGadgetRoot, entry->d_name);
				if (sysfs_read(strjin(gadget, (char*)"/UDC")) != nullptr)
				{
					gadgetRoot = gadget;
					break;
				}
			}
		}
	return gadgetRoot;
}

char *get_config_root()
{
	char *gadgetRoot = get_gadget_root();
	if (gadgetRoot == nullptr)
	{
		return nullptr;
	}
	char *usbConfigRoot = strjin(gadgetRoot, (char*)"/configs/");
	char *configRoot = nullptr;

	struct dirent *entry = nullptr;
	DIR *dp = nullptr;
	dp = opendir(usbConfigRoot);
	if (dp != nullptr)
		while ((entry = readdir(dp)))
		{
			if (entry->d_name[0] != '.')
			{
				configRoot = strjin(usbConfigRoot, entry->d_name);
				break;
			}
		}
	return configRoot;
}

void mount_iso(char *iso_path, char *cdrom, char *ro)
{
	char *gadgetRoot = get_gadget_root();
	if (gadgetRoot == nullptr)
	{
		std::cerr << "No active gadget found" << std::endl;
		return;
	}
	char *configRoot = get_config_root();
	char *udc = get_udc();
	printf("udc found %s\n", udc);
	char *functionRoot = strjin(gadgetRoot, (char*)"/functions");
	char *massStorageRoot = strjin(functionRoot, (char*)"/mass_storage.0");
	char *lunRoot = strjin(massStorageRoot, (char*)"/lun.0");
	
	char *stallFile = strjin(massStorageRoot, (char*)"/stall");
	char *udcFile = strjin(gadgetRoot, (char*)"/UDC");
	char *lunFile = strjin(lunRoot, (char*)"/file");
	char *lunCdRom = strjin(lunRoot, (char*)"/cdrom");
	char *lunRo = strjin(lunRoot, (char*)"/ro");

	set_udc((char*)"", gadgetRoot);
	
	if (!isdir(massStorageRoot))
	{
		mkdir(massStorageRoot, S_IRWXU | S_IRWXG | S_IROTH | S_IXOTH);
	}
	if (!isdir(strjin(configRoot, (char*)"/mass_storage.0")))
	{
		symlink(massStorageRoot, strjin(configRoot, (char*)"/mass_storage.0"));
	}
	sysfs_write(lunFile, iso_path);
	sysfs_write(lunCdRom, cdrom);
	sysfs_write(lunRo, ro);

	set_udc(udc, gadgetRoot);
}

void set_udc(char *udc, char *gadget)
{
	char *udcFile = strjin(gadget, (char*)"/UDC");
	sysfs_write(udcFile, udc);
}

char *get_udc()
{
	char *gadget_root = get_gadget_root();
	if (gadget_root == nullptr)
	{
		return nullptr;
	}
	char *udcFile = strjin(gadget_root, (char*)"/UDC");
	return sysfs_read(udcFile);
}