package net.sourceforge.fenixedu.domain;

import java.util.ArrayList;
import java.util.Collection;
import java.util.List;

import net.sourceforge.fenixedu.domain.accessControl.EveryoneGroup;
import net.sourceforge.fenixedu.domain.accessControl.Group;
import net.sourceforge.fenixedu.domain.accessControl.GroupUnion;
import net.sourceforge.fenixedu.domain.accessControl.PersistentGroup;
import net.sourceforge.fenixedu.domain.exceptions.DomainException;
import net.sourceforge.fenixedu.domain.organizationalStructure.Unit;
import net.sourceforge.fenixedu.injectionCode.AccessControl;
import net.sourceforge.fenixedu.injectionCode.IGroup;
import dml.runtime.RelationAdapter;

public class UnitFile extends UnitFile_Base {

    static {
	FileTagging.addListener(new RelationAdapter<UnitFile, UnitFileTag>() {

	    @Override
	    public void afterRemove(UnitFile file, UnitFileTag tag) {
		super.afterRemove(file, tag);
		if (file != null && tag != null && tag.getTaggedFilesCount() == 0) {
		    tag.delete();
		}
	    }

	});
    }

    public UnitFile(Unit unit, Person person, String description, String tags, String filename, String displayName,
	    String mimeType, String checksum, String checksumAlgorithm, int size, String uniqueId, Group permittedGroup) {
	super();
	setUnit(unit);
	setUploader(person);
	setDescription(description);
	if (tags != null && tags.length() > 0) {
	    setUnitFileTags(tags);
	}
	init(filename, displayName, mimeType, checksum, checksumAlgorithm, size, uniqueId, permittedGroup);
    }

    public void setUnitFileTags(String tag) {
	getUnitFileTags().clear();
	String[] tagNames = tag.split("\\p{Space}+");
	for (int i = 0; i < tagNames.length; i++) {
	    UnitFileTag unitFileTag = getUnit().getUnitFileTag(tagNames[i].trim());
	    addUnitFileTags((unitFileTag != null) ? unitFileTag : new UnitFileTag(getUnit(), tagNames[i].trim()));
	}
    }

    public void delete() {
	if (isEditableByCurrentUser()) {
	    removeUnit();
	    for (; !getUnitFileTags().isEmpty(); getUnitFileTags().get(0).removeTaggedFiles(this))
		;
	    removeRootDomainObject();
	    removeUploader();
	    super.deleteDomainObject();
	} else {
	    throw new DomainException("error.cannot.delete.file");
	}
    }

    public boolean isEditableByUser(Person person) {
	return getUploader().equals(person);
    }

    public boolean isEditableByCurrentUser() {
	return isEditableByUser(AccessControl.getPerson());
    }

    public void updatePermissions(PersistentGroup group) {
	Group currentGroup = getPermittedGroup();
	if (currentGroup instanceof GroupUnion) {
	    setPermittedGroup(updateGroupUnion((GroupUnion) currentGroup, group));
	} else {
	    if (currentGroup.equals(group)) {
		setPermittedGroup(new EveryoneGroup());
	    }
	}
    }

    private Group updateGroupUnion(GroupUnion group, PersistentGroup groupToRemove) {
	return new GroupUnion(processGroup(group, groupToRemove));
    }

    private List<IGroup> processGroup(GroupUnion groupUnion, PersistentGroup groupToRemove) {
	List<IGroup> groups = new ArrayList<IGroup>();
	for (IGroup group : groupUnion.getChildren()) {
	    if (group instanceof GroupUnion) {
		groups.addAll(processGroup((GroupUnion) group, groupToRemove));
	    } else {
		if (!group.equals(groupToRemove)) {
		    groups.add(group);
		}
	    }
	}
	return groups;
    }

    public boolean hasUnitFileTags(Collection<UnitFileTag> tags) {
	return getUnitFileTags().containsAll(tags);
    }

}