/* 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 3 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, see <http://www.gnu.org/licenses/>.
 *
 */

#include "common/archive.h"
#include "common/fs.h"
#include "common/system.h"
#include "common/textconsole.h"
#include "common/memstream.h"

namespace Common {

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

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

SeekableReadStream *GenericArchiveMember::createReadStream() const {
	return _parent->createReadStreamForMember(_name);
}


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

	String patternString = pattern.toString();
	int matches = 0;
	const char *wildcardExclusions = matchPathComponents ? NULL : "/";

	ArchiveMemberList::const_iterator it = allNames.begin();
	for (; it != allNames.end(); ++it) {
		// TODO: We match case-insenstivie for now, our API does not define whether that's ok or not though...
		// For our use case case-insensitive is probably what we want to have though.
		if ((*it)->getName().matchString(patternString, true, wildcardExclusions)) {
			list.push_back(*it);
			matches++;
		}
	}

	return matches;
}

SeekableReadStream *MemcachingCaseInsensitiveArchive::createReadStreamForMember(const Path &path) const {
	String translated = translatePath(path);
	bool isNew = false;
	if (!_cache.contains(translated)) {
		_cache[translated] = readContentsForPath(translated);
		isNew = true;
	}

	SharedArchiveContents* entry = &_cache[translated];

	// Errors and missing files. Just return nullptr,
	// no need to create stream.
	if (entry->isFileMissing())
		return nullptr;

	// Check whether the entry is still valid as WeakPtr might have expired.
	if (!entry->makeStrong()) {
		// If it's expired, recreate the entry.
		_cache[translated] = readContentsForPath(translated);
		entry = &_cache[translated];
		isNew = true;
	}

	// It's possible that recreation failed in case of e.g. network
	// share going offline.
	if (entry->isFileMissing())
		return nullptr;

	// Now we have a valid contents reference. Make stream for it.
	Common::MemoryReadStream *memStream = new Common::MemoryReadStream(entry->getContents(), entry->getSize());

	// If the entry was just created and it's too big for strong caching,
	// mark the copy in cache as weak
	if (isNew && entry->getSize() > _maxStronglyCachedSize) {
		entry->makeWeak();
	}

	return memStream;
}


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

SearchSet::ArchiveNodeList::const_iterator SearchSet::find(const String &name) const {
	ArchiveNodeList::const_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) {
	ArchiveNodeList::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::addDirectory(const String &name, const String &directory, int priority, int depth, bool flat) {
	FSNode dir(directory);
	addDirectory(name, dir, priority, depth, flat);
}

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

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

void SearchSet::addSubDirectoriesMatching(const FSNode &directory, String origPattern, bool ignoreCase, int priority, int depth, bool flat) {
	FSList subDirs;
	if (!directory.getChildren(subDirs))
		return;

	String nextPattern, pattern;
	String::const_iterator sep = Common::find(origPattern.begin(), origPattern.end(), '/');
	if (sep != origPattern.end()) {
		pattern = String(origPattern.begin(), sep);

		++sep;
		if (sep != origPattern.end())
			nextPattern = String(sep, origPattern.end());
	} else {
		pattern = origPattern;
	}

	// TODO: The code we have for displaying all matches, which vary only in case, might
	// be a bit overhead, but as long as we want to display all useful information to the
	// user we will need to keep track of all directory names added so far. We might
	// want to reconsider this though.
	typedef HashMap<String, bool, IgnoreCase_Hash, IgnoreCase_EqualTo> MatchList;
	MatchList multipleMatches;
	MatchList::iterator matchIter;

	for (FSList::const_iterator i = subDirs.begin(); i != subDirs.end(); ++i) {
		String name = i->getName();

		if (matchString(name.c_str(), pattern.c_str(), ignoreCase)) {
			matchIter = multipleMatches.find(name);
			if (matchIter == multipleMatches.end()) {
				multipleMatches[name] = true;
			} else {
				if (matchIter->_value) {
					warning("Clash in case for match of pattern \"%s\" found in directory \"%s\": \"%s\"", pattern.c_str(), directory.getPath().c_str(), matchIter->_key.c_str());
					matchIter->_value = false;
				}

				warning("Clash in case for match of pattern \"%s\" found in directory \"%s\": \"%s\"", pattern.c_str(), directory.getPath().c_str(), name.c_str());
			}

			if (nextPattern.empty())
				addDirectory(name, *i, priority, depth, flat);
			else
				addSubDirectoriesMatching(*i, nextPattern, ignoreCase, priority, depth, flat);
		}
	}
}

void SearchSet::remove(const String &name) {
	ArchiveNodeList::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 (ArchiveNodeList::iterator i = _list.begin(); i != _list.end(); ++i) {
		if (i->_autoFree)
			delete i->_arc;
	}

	_list.clear();
}

void SearchSet::setPriority(const String &name, int priority) {
	ArchiveNodeList::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 Path &path) const {
	if (path.empty())
		return false;

	ArchiveNodeList::const_iterator it = _list.begin();
	for (; it != _list.end(); ++it) {
		if (it->_arc->hasFile(path))
			return true;
	}

	return false;
}

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

	ArchiveNodeList::const_iterator it = _list.begin();
	for (; it != _list.end(); ++it)
		matches += it->_arc->listMatchingMembers(list, pattern, matchPathComponents);

	return matches;
}

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

	ArchiveNodeList::const_iterator it = _list.begin();
	for (; it != _list.end(); ++it)
		matches += it->_arc->listMembers(list);

	return matches;
}

const ArchiveMemberPtr SearchSet::getMember(const Path &path) const {
	if (path.empty())
		return ArchiveMemberPtr();

	ArchiveNodeList::const_iterator it = _list.begin();
	for (; it != _list.end(); ++it) {
		if (it->_arc->hasFile(path))
			return it->_arc->getMember(path);
	}

	return ArchiveMemberPtr();
}

SeekableReadStream *SearchSet::createReadStreamForMember(const Path &path) const {
	if (path.empty())
		return nullptr;

	ArchiveNodeList::const_iterator it = _list.begin();
	for (; it != _list.end(); ++it) {
		SeekableReadStream *stream = it->_arc->createReadStreamForMember(path);
		if (stream)
			return stream;
	}

	return nullptr;
}


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

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.
	if (g_system)
		g_system->addSysArchivesToSearchSet(*this, -1);

#ifndef __ANDROID__
	// Add the current dir as a very last resort.
	// See also bug #3984.
	// But don't do this for Android platform, since it may lead to crashes
	addDirectory(".", ".", -2);
#endif
}

DECLARE_SINGLETON(SearchManager);

} // namespace Common