/*
 * This file is a part of Winix
 * and is not publicly distributed
 * 
 * Copyright (c) 2010, Tomasz Sowa
 * All rights reserved.
 * 
 */
 
#include "system.h"
#include "misc.h"
#include "error.h"
#include "notify.h"
#include "functions/functions.h"
#include "templates/templates.h"



void System::SetRequest(Request * prequest)
{
	request = prequest;
}


void System::SetConfig(Config * pconfig)
{
	config = pconfig;
}


void System::SetDb(Db * pdb)
{
	db = pdb;
}


void System::SetFunctions(Functions * pfunctions)
{
	functions = pfunctions;
}


void System::SetTemplates(Templates * ptemplates)
{
	templates = ptemplates;
}



void System::Init()
{
	dirs.SetDb(db);
	dirs.SetRequest(request);

	dirs.ReadDirs();

	mounts.SetDirs(&dirs);
	mounts.SetDb(db);
	mounts.SetRequest(request);
	mounts.ReadMounts();

	users.SetRequest(request);
	users.ReadUsers(db);
	groups.ReadGroups(db); // !! chwilowe przekazanie argumentu, db bedzie zmienione

	rebus.SetRequest(request);
	rebus.Init();
}


// !! mozna zrobic jakas obsluge kiedy nie mozemy sie redirectnac, np gdy wystapil blad
// !! moze zwracac jakas wartosc?
void System::RedirectTo(const Item & item, const char * postfix)
{
	request->redirect_to = config->base_url;

	if( item.type == Item::dir )
	{
		// item_id is pointing to a directory
		dirs.MakePath(item.id, path);
		request->redirect_to += path;
	}
	else
	{
		if( !dirs.MakePath(item.parent_id, path) )
			log << log1 << "Content: Can't redirect: no dirs for item id: " << item.id << logend;
			
		request->redirect_to += path;
		request->redirect_to += item.url;
	}

	if( postfix )
		request->redirect_to += postfix;
}



void System::RedirectTo(long item_id, const char * postfix)
{
std::string path;
Item * pdir;
	
	request->redirect_to = config->base_url;
	pdir = dirs.GetDir(item_id);


	if( pdir )
	{
		// item_id is pointing to a directory
		dirs.MakePath(pdir->id, path);
		request->redirect_to += path;
	}
	else
	{
		// !! zrobic nowy interfejs
		// !! GetItem pozamieniac na GetFile
		// !! i nie uzywac request->item_table (zrobic sobie lokalny tutaj)
		db->GetItem(request->item_table, item_id);
	
		if( !request->item_table.empty() )
		{
			if( !dirs.MakePath(request->item_table[0].parent_id, path) )
				log << log1 << "Content: Can't redirect: no dirs for item id: " << request->item_table[0].id << ", requested directory id: " << request->item_table[0].parent_id << logend;
				
			request->redirect_to += path + request->item_table[0].url;
		}
		else
		{
			log << log1 << "Content: Can't redirect: no such item: id: " << item_id << logend;	
		}
	}

	if( postfix )
		request->redirect_to += postfix;
}


void System::RedirectToLastDir()
{
	// !! dac sprawdzenie czy istnieje
	RedirectTo( *request->dir_table.back() );
}


void System::RedirectToLastItem()
{
	if( request->is_item )
		RedirectTo(request->item);
	else
		RedirectTo( *request->dir_table.back() );// !! dac sprawdzenie czy istnieje
}


void System::PrepareUrl(Item & item)
{
	TrimWhite(item.url);

	if( item.url.empty() )
		item.url = item.subject; // if the subject is empty then the url will be corrected by CorrectUrlOnlyAllowedChar()
		
	CorrectUrlOnlyAllowedChar(item.url);
	
	if( functions->Find(item.url) )
	{
		// the name provided by an user is the same as a name of a function
		// we add one underscore character at the beginning
		
		// names of functions should not begin with an underscore '_'
		// and we can simply add one '_' at the beginning
		// and the name will be unique
		item.url.insert(item.url.begin(), '_');
	}
}


bool System::CanChangeUser(const Item & item, long new_user_id)
{
	if( !request->session )
		// session must be set
		return false;
	
	if( request->session->puser && request->session->puser->super_user )
		// super user is allowed everything
		return true;
		
	if( item.user_id != new_user_id )
		// only super user can change the owner of an item
		return false;

return true;
}


bool System::CanChangeGroup(const Item & item, long new_group_id)
{
	if( !request->session )
		// session must be set
		return false;

	if( request->session->puser && request->session->puser->super_user )
		// super user is allowed everything
		return true;

	if( item.group_id != new_group_id )
	{
		// user is allowed to change the group only if he is an owner of the item
		// he can change only into a group in which he is a member of, or into a 'no_group'
		
		if( !request->session->puser )
			return false;
			
		if( request->session->puser->id != item.user_id )
			return false;
			
		if( new_group_id == -1 )
			return true;
			
		if( !request->session->puser->IsMemberOf(new_group_id) )
			return false;
			
		// is logged, is the owner of the item, is the member of the new group
	}
	
return true;
}


bool System::CanChangePrivileges(const Item & item, int new_priv)
{
	if( !request->session )
		// session must be set
		return false;

	if( request->session->puser && request->session->puser->super_user )
		// super user is allowed everything
		return true;

	if( item.privileges != new_priv )
	{
		// the owner of an item is allowed to change the privileges		
		
		if( !request->session->puser )
			return false;
			
		if( request->session->puser->id != item.user_id )
			return false;
	}

return true;
}



bool System::HasAccess(const Item & item, int mask)
{
	if( !request->session )
		// session must be set
		return false;

	if( request->session->puser && request->session->puser->super_user )
		// super user is allowed everything
		return true;
	
	if( request->session->puser && request->session->puser->id == item.user_id )
	{
		// the owner
		return ((item.privileges >> 6) & mask) == mask;
	}
	
	if( request->session->puser && request->session->puser->IsMemberOf(item.group_id) )
	{
		// group
		return ((item.privileges >> 3) & mask) == mask;
	}
	
	// others
	
return (item.privileges & mask) == mask;
}


bool System::HasReadAccess(const Item & item)
{
	return HasAccess(item, 4);	
}


bool System::HasWriteAccess(const Item & item)
{
	return HasAccess(item, 2);	
}


bool System::HasReadWriteAccess(const Item & item)
{
	return HasAccess(item, 6);	// r+w
}


bool System::HasReadExecAccess(const Item & item)
{
	if( request->session && request->session->puser && request->session->puser->super_user )
	{
		// there must be at least one 'x' (for the root)
	
		return (item.privileges & 0111) != 0;
	}
	
	return HasAccess(item, 5);	// r+x
}





bool System::HasReadExecAccessToPath(long dir_id)
{
	while( true )
	{
		Item * pdir = dirs.GetDir(dir_id);

		if( !pdir )
			return false;	

		if( !HasReadExecAccess(*pdir) )
			return false;

		dir_id = pdir->parent_id;

		if( dir_id == -1 )
			return true;
	}
}


bool System::DirsHaveReadExecPerm()
{
	std::vector<Item*>::iterator i;
	
	for(i = request->dir_table.begin() ; i!=request->dir_table.end() ; ++i)
	{
		if( !HasReadExecAccess(**i) )
			return false;
	}
	
return true;	
}


// if we don't have access we only remove the item from the table
void System::CheckAccessToItems(std::vector<Item> & item_table)
{
size_t i = 0;

	while( i < item_table.size() )
	{
		if( !HasReadAccess(item_table[i]) )
		{
			item_table.erase(item_table.begin() + i);
		}
		else
		{
			i += 1;
		}
	}
}



bool System::CanUseHtml(long user_id)
{
	return IsMemberOfGroup(user_id, "allow_html");
}


bool System::CanUseBBCode(long user_id)
{
	// logged users can use bbcode
	return (user_id != -1);
}


bool System::CanUseRaw(long user_id)
{
	return IsMemberOfGroup(user_id, "allow_raw");
}



bool System::IsMemberOfGroup(long user_id, const char * group_name)
{
	User * puser = users.GetUser(user_id);
	
	if( !puser )
		return false;
	
	if( puser->super_user )
		return true;
	
	long group = groups.GetGroupId(group_name);
	
	if( group == -1 )
		// there is no such a group
		return false;
	
	if( puser->IsMemberOf(group) )
		return true;
		
return false;
}






bool System::MakePathSimpleFs(std::string & path, long dir_id, bool create_dir)
{
	if( config->auth_simplefs_dir.empty() )
	{
		log << log1 << "System: auth_simplefs_dir is not set in the config file" << logend;
		return false;
	}

	if( !dirs.MakePath(dir_id, path) )
		return false;

	if( create_dir && !CreateDirs(config->auth_simplefs_dir, path, 0755) )
		return false;

	path.insert(0, config->auth_simplefs_dir);

return true;
}




// the path depends on id
bool System::MakePathHashFs(std::string & path, long id, bool create_dir)
{
char buffer[50];
char * hash = buffer;

	// get 'id' as hexadecimal
	buffer[0] = '0';
	sprintf(buffer+1, "%lx", (unsigned long)id);

	path = config->auth_hashfs_dir;
	if( path.empty() )
	{
		log << log1 << "System: auth_hashfs_dir is not set in the config file" << logend;
		return false;
	}

	path += '/';
	
	// make sure that the length is even
	if( (strlen(hash) & 1) != 0 )
		hash = buffer + 1; // the first character was zero

	// creating dirs without the last part
	// the last part is a part of a file
	for(size_t i=0 ; hash[i] != 0 ; i+=2)
	{
		path += hash[i];
		path += hash[i+1];

		if( hash[i+2] != 0 )
		{
			if( create_dir && !CreateDir(path, 0755) )
				return false;

			path += '/';
		}
	}

	// one character more to make sure the path is unique
	// (we can have a directory without the character)
	path += "_";

return true;
}


// making a complete path to a static file
bool System::MakePath(const Item & item, std::string & path, bool create_dir)
{
bool res;

	Mount * pmount = mounts.CalcMount(item.parent_id);

	if( !pmount || pmount->fs == Mount::simplefs )
	{
		res = MakePathSimpleFs(path, item.parent_id, create_dir);
	}
	else
	{
		res = MakePathHashFs(path, item.id, create_dir);
	}

	if( res )
		path += item.url;
	else
		path.clear();

return res;
}



bool System::MakePath(Item & item, bool create_dir)
{
	return MakePath(item, item.auth_path, create_dir);
}



Error System::AddFile(Item & item)
{
	if( item.type == Item::dir )
		return WINIX_ERR_FILE_EXPECTED;

	Error status = db->AddItem(item);
	
	if( status == WINIX_ERR_OK )
	{
		log << log2 << "System: added a new file, url: " << item.url << ", id: " << item.id
			<< ", parent_id: " << item.parent_id << logend;

		request->notify_code |= WINIX_NOTIFY_ITEM_ADD;
	}

return status;
}



Error System::EditFile(Item & item, bool with_url)
{
	if( item.type == Item::dir )
		return WINIX_ERR_FILE_EXPECTED;

	if( request->session && request->session->puser )
		request->item.modification_user_id = request->session->puser->id;
	else
		request->item.modification_user_id = -1;

	item.SetDateModifyToNow();
	Error status = db->EditItemById(item, with_url);
	
	if( status == WINIX_ERR_OK )
	{
		TemplatesFunctions::pattern_cacher.UpdatePattern(item);
		log << log2 << "System: modified an item" << logend;

		request->notify_code |= WINIX_NOTIFY_ITEM_EDIT;
	}

return status;
}




Error System::CheckSpecialFile(const Item & item)
{
	static std::string fstab = "fstab";

	Item * etc = dirs.GetEtcDir();

	if( !etc )
		return WINIX_NOTHING_TO_DO;

	if( item.parent_id != etc->id )
		return WINIX_NOTHING_TO_DO;

	if( item.url == fstab )
	{
		log << log3 << "System: reloading mount points" << logend;

		Error status = mounts.ReadMounts(item.content);
		templates->ReadNewIndexTemplates();
		
		return status;
	}

return WINIX_NOTHING_TO_DO;
}