/* ScummVM - Graphic Adventure Engine
 *
 * ScummVM is the legal property of its developers, whose names
 * are too numerous to list here. Please refer to the COPYRIGHT
 * file distributed with this source distribution.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.

 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.

 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 * $URL$
 * $Id$
 *
 */

#include "common/archive.h"
#include "common/fs.h"
#include "common/util.h"
#include "common/system.h"

namespace Common {

GenericArchiveMember::GenericArchiveMember(String name, Archive *parent)
	: _parent(parent), _name(name) {
}

String GenericArchiveMember::getName() const {
	return _name;
}

SeekableReadStream *GenericArchiveMember::open() {
	return _parent->openFile(_name);
}


int Archive::listMatchingMembers(ArchiveMemberList &list, const String &pattern) {
	// Get all "names" (TODO: "files" ?)
	ArchiveMemberList allNames;
	listMembers(allNames);

	int matches = 0;

	// need to match lowercase key
	String lowercasePattern = pattern;
	lowercasePattern.toLowercase();

	ArchiveMemberList::iterator it = allNames.begin();
	for ( ; it != allNames.end(); it++) {
		if ((*it)->getName().matchString(lowercasePattern)) {
			list.push_back(*it);
			matches++;
		}
	}

	return matches;
}

/**
 *  FSDirectoryMemeber is the implementation of ArchiveMember used by
 *  by FSDirectory. It is right now a light wrapper or FSNode.
 */
class FSDirectoryMember : public ArchiveMember {
	FSNode 	_node;

public:
	FSDirectoryMember(FSNode &node) : _node(node) {
	}

	/*
		NOTE/FIXME: since I assume that the only use case for getName()
		is for error messages, I am returning the full path of the node
		here. This seems better than we did before, when matchPattern
		and getAllNames used to work with StringList, and we used to
		put the relative path of the file to the list instead.
	*/
	String getName() const {
		return _node.getPath();
	}

	SeekableReadStream *open() {
		return _node.openForReading();
	}
};

typedef SharedPtr<FSDirectoryMember> FSDirectoryMemberPtr;

FSDirectory::FSDirectory(const FSNode &node, int depth)
  : _node(node), _cached(false), _depth(depth) {
}

FSDirectory::FSDirectory(const String &prefix, const FSNode &node, int depth)
  : _node(node), _cached(false), _depth(depth) {

	setPrefix(prefix);
}

FSDirectory::FSDirectory(const String &name, int depth)
  : _node(name), _cached(false), _depth(depth) {
}

FSDirectory::FSDirectory(const String &prefix, const String &name, int depth)
  : _node(name), _cached(false), _depth(depth) {

	setPrefix(prefix);
}

FSDirectory::~FSDirectory() {
}

void FSDirectory::setPrefix(const String &prefix) {
	_prefix = prefix;

	if (!_prefix.empty() && !_prefix.hasSuffix("/")) {
		_prefix += "/";
	}
}

FSNode FSDirectory::getFSNode() const {
	return _node;
}

FSNode FSDirectory::lookupCache(NodeCache &cache, const String &name) {
	// make caching as lazy as possible
	if (!name.empty()) {
		if (!_cached) {
			cacheDirectoryRecursive(_node, _depth, _prefix);
			_cached = true;
		}

		if (cache.contains(name))
			return cache[name];
	}

	return FSNode();
}

bool FSDirectory::hasFile(const String &name) {
	if (name.empty() || !_node.isDirectory()) {
		return false;
	}

	FSNode node = lookupCache(_fileCache, name);
	return node.exists();
}

ArchiveMemberPtr FSDirectory::getMember(const String &name) {
	if (name.empty() || !_node.isDirectory()) {
		return ArchiveMemberPtr();
	}

	FSNode node = lookupCache(_fileCache, name);

	if (!node.exists()) {
		warning("FSDirectory::getMember: FSNode does not exist");
		return ArchiveMemberPtr();
	} else if (node.isDirectory()) {
		warning("FSDirectory::getMember: FSNode is a directory");
		return ArchiveMemberPtr();
	}

	return ArchiveMemberPtr(new FSDirectoryMember(node));
}

SeekableReadStream *FSDirectory::openFile(const String &name) {
	if (name.empty() || !_node.isDirectory()) {
		return 0;
	}

	FSNode node = lookupCache(_fileCache, name);

	if (!node.exists()) {
		warning("FSDirectory::openFile: FSNode does not exist");
		return 0;
	} else if (node.isDirectory()) {
		warning("FSDirectory::openFile: FSNode is a directory");
		return 0;
	}

	SeekableReadStream *stream = node.openForReading();
	if (!stream) {
		warning("FSDirectory::openFile: Can't create stream for file '%s'", name.c_str());
	}

	return stream;
}

FSDirectory *FSDirectory::getSubDirectory(const String &name, int depth) {
	return getSubDirectory(String::emptyString, name, depth);
}

FSDirectory *FSDirectory::getSubDirectory(const String &prefix, const String &name, int depth) {
	if (name.empty() || !_node.isDirectory()) {
		return 0;
	}

	FSNode node = lookupCache(_subDirCache, name);
	return new FSDirectory(prefix, node, depth);
}

void FSDirectory::cacheDirectoryRecursive(FSNode node, int depth, const String& prefix) {
	if (depth <= 0) {
		return;
	}

	FSList list;
	node.getChildren(list, FSNode::kListAll, false);

	FSList::iterator it = list.begin();
	for ( ; it != list.end(); it++) {
		String name = prefix + (*it).getName();

		// don't touch name as it might be used for warning messages
		String lowercaseName = name;
		lowercaseName.toLowercase();

		// since the hashmap is case insensitive, we need to check for clashes when caching
		if ((*it).isDirectory()) {
			if (_subDirCache.contains(lowercaseName)) {
				warning("FSDirectory::cacheDirectory: name clash when building cache, ignoring sub-directory '%s'", name.c_str());
			} else {
				cacheDirectoryRecursive(*it, depth - 1, lowercaseName + "/");
				_subDirCache[lowercaseName] = *it;
			}
		} else {
			if (_fileCache.contains(lowercaseName)) {
				warning("FSDirectory::cacheDirectory: name clash when building cache, ignoring file '%s'", name.c_str());
			} else {
				_fileCache[lowercaseName] = *it;
			}
		}
	}

}

int FSDirectory::listMatchingMembers(ArchiveMemberList &list, const String &pattern) {
	if (!_node.isDirectory())
		return 0;

	// Cache dir data
	if (!_cached) {
		cacheDirectoryRecursive(_node, _depth, "");
		_cached = true;
	}

	String lowercasePattern(pattern);
	lowercasePattern.toLowercase();

	int matches = 0;
	NodeCache::iterator it = _fileCache.begin();
	for ( ; it != _fileCache.end(); it++) {
		if ((*it)._key.matchString(lowercasePattern)) {
			list.push_back(FSDirectoryMemberPtr(new FSDirectoryMember((*it)._value)));
			matches++;
		}
	}
	return matches;
}

int FSDirectory::listMembers(ArchiveMemberList &list) {
	return listMatchingMembers(list, "*");
}





SearchSet::ArchiveList::iterator SearchSet::find(const String &name) const {
	ArchiveList::iterator it = _list.begin();
	for ( ; it != _list.end(); it++) {
		if ((*it)._name == name) {
			break;
		}
	}
	return it;
}

/*
	Keep the nodes sorted according to descending priorities.
	In case two or node nodes have the same priority, insertion
	order prevails.
*/
void SearchSet::insert(const Node &node) {
	ArchiveList::iterator it = _list.begin();
	for ( ; it != _list.end(); it++) {
		if ((*it)._priority < node._priority) {
			break;
		}
	}
	_list.insert(it, node);
}

void SearchSet::add(const String &name, Archive *archive, int priority, bool autoFree) {
	if (find(name) == _list.end()) {
		Node node(priority, name, archive, autoFree);
		insert(node);
	} else {
		if (autoFree)
			delete archive;
		warning("SearchSet::add: archive '%s' already present", name.c_str());
	}

}

void SearchSet::remove(const String &name) {
	ArchiveList::iterator it = find(name);
	if (it != _list.end()) {
		if (it->_autoFree)
			delete it->_arc;
		_list.erase(it);
	}
}

bool SearchSet::hasArchive(const String &name) const {
	return (find(name) != _list.end());
}

void SearchSet::clear() {
	for (ArchiveList::iterator i = _list.begin(); i != _list.end(); ++i) {
		if (i->_autoFree)
			delete i->_arc;
	}

	_list.clear();
}

void SearchSet::setPriority(const String &name, int priority) {
	ArchiveList::iterator it = find(name);
	if (it == _list.end()) {
		warning("SearchSet::setPriority: archive '%s' is not present", name.c_str());
		return;
	}

	if (priority == (*it)._priority) {
		return;
	}

	Node node(*it);
	_list.erase(it);
	node._priority = priority;
	insert(node);
}

bool SearchSet::hasFile(const String &name) {
	if (name.empty()) {
		return false;
	}

	ArchiveList::iterator it = _list.begin();
	for ( ; it != _list.end(); it++) {
		if ((*it)._arc->hasFile(name)) {
			return true;
		}
	}

	return false;
}

int SearchSet::listMatchingMembers(ArchiveMemberList &list, const String &pattern) {
	int matches = 0;

	ArchiveList::iterator it = _list.begin();
	for ( ; it != _list.end(); it++) {
		matches += (*it)._arc->listMatchingMembers(list, pattern);
	}

	return matches;
}

int SearchSet::listMembers(ArchiveMemberList &list) {
	int matches = 0;

	ArchiveList::iterator it = _list.begin();
	for ( ; it != _list.end(); it++) {
		matches += (*it)._arc->listMembers(list);
	}

	return matches;
}

ArchiveMemberPtr SearchSet::getMember(const String &name) {
	if (name.empty()) {
		return ArchiveMemberPtr();
	}

	ArchiveList::iterator it = _list.begin();
	for ( ; it != _list.end(); it++) {
		if ((*it)._arc->hasFile(name)) {
			return (*it)._arc->getMember(name);
		}
	}

	return ArchiveMemberPtr();
}

SeekableReadStream *SearchSet::openFile(const String &name) {
	if (name.empty()) {
		return 0;
	}

	ArchiveList::iterator it = _list.begin();
	for ( ; it != _list.end(); it++) {
		if ((*it)._arc->hasFile(name)) {
			return (*it)._arc->openFile(name);
		}
	}

	return 0;
}


DECLARE_SINGLETON(SearchManager);

SearchManager::SearchManager() {
	clear();	// Force a reset
}

void SearchManager::addDirectory(const String &name, const String &directory, int priority, int depth) {
	FSNode dir(directory);
	addDirectory(name, dir, priority, depth);
}

void SearchManager::addDirectory(const String &name, const FSNode &dir, int priority, int depth) {
	if (!dir.exists() || !dir.isDirectory())
		return;

	add(name, new FSDirectory(dir, depth), priority);
}

void SearchManager::clear() {
	SearchSet::clear();

	// Always keep system specific archives in the SearchManager.
	// But we give them a lower priority than the default priority (which is 0),
	// so that archives added by client code are searched first.
	g_system->addSysArchivesToSearchSet(*this, -1);

	// Add the current dir as a very last resort.
	// See also bug #2137680.
	addDirectory(".", ".", -2);
}

} // namespace Common