/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */

package ee.tlu.htk.dippler.entities;

import ee.tlu.htk.dippler.utils.Utility;
import java.io.Serializable;
import java.util.Calendar;
import java.util.Collection;
import java.util.Date;
import java.util.HashSet;
import java.util.Set;
import javax.persistence.Basic;
import javax.persistence.CascadeType;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.FetchType;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.JoinTable;
import javax.persistence.Lob;
import javax.persistence.ManyToMany;
import javax.persistence.ManyToOne;
import javax.persistence.NamedQueries;
import javax.persistence.NamedQuery;
import javax.persistence.OneToMany;
import javax.persistence.Table;
import javax.persistence.TableGenerator;
import javax.persistence.Temporal;
import javax.persistence.TemporalType;
import javax.persistence.Transient;
import javax.xml.bind.annotation.XmlElement;
import javax.xml.bind.annotation.XmlElementWrapper;
import javax.xml.bind.annotation.XmlRootElement;

/**
 *
 * @author metz
 */
@XmlRootElement
@Entity
@Table(name = "assignment")
@NamedQueries({
    @NamedQuery(name = "Assignment.findAll", query = "SELECT a FROM Assignment a ORDER BY a.end DESC"),
    @NamedQuery(name = "Assignment.findById", query = "SELECT a FROM Assignment a WHERE a.id = :id"),
    @NamedQuery(name = "Assignment.findByTitle", query = "SELECT a FROM Assignment a WHERE a.title = :title ORDER BY a.end DESC"),
    @NamedQuery(name = "Assignment.findByStart", query = "SELECT a FROM Assignment a WHERE a.start = :start ORDER BY a.start DESC"),
    @NamedQuery(name = "Assignment.findByEnd", query = "SELECT a FROM Assignment a WHERE a.end = :end ORDER BY a.end DESC"),
    @NamedQuery(name = "Assignment.findByCourse", query = "SELECT a FROM Assignment a WHERE a.course = :course ORDER BY a.end DESC"),
    @NamedQuery(name = "Assignment.findByCourse_WP", query = "SELECT a FROM Assignment a WHERE a.start <= :start_date AND a.course = :course  ORDER BY a.end DESC"),
    @NamedQuery(name = "Assignment.findByCreated", query = "SELECT a FROM Assignment a WHERE a.created = :created ORDER BY a.created DESC"),
    @NamedQuery(name = "Assignment.findByModified", query = "SELECT a FROM Assignment a WHERE a.modified = :modified ORDER BY a.modified DESC")})
public class Assignment implements Serializable {
    private static final long serialVersionUID = 1L;
    
    @Id
    @GeneratedValue(generator = "AssignmentID")
    @TableGenerator(name="AssignmentID", table="id_gen", 
            pkColumnName="ID_NAME", 
            valueColumnName = "ID_VAL",
            pkColumnValue="LAST_ASSIGNMENT",
            allocationSize=1)
    @Basic(optional = false)
    @Column(name = "id")
    private Long id;

    @Basic(optional = false)
    @Column(name = "subtype")
    private String subtype;

    @Column(name = "type")
    private String type;

    @Basic(optional = false)
    @Column(name = "title")
    private String title;

    @Basic(optional = false)
    @Lob
    @Column(name = "description")
    private String description;

    @Basic(optional = true)
    @Lob
    @Column(name = "structure")
    private String structure;

    @Basic(optional = false)
    @Column(name = "start")
    private int start;

    @Basic(optional = false)
    @Column(name = "end")
    private int end;

    @Basic(optional = false)
    @Column(name = "maxpoints")
    private int maxpoints;

    @Basic(optional = false)
    @Column(name = "created")
    @Temporal(TemporalType.TIMESTAMP)
    private Date created = new Date();

    @JoinColumn(name = "creator", referencedColumnName = "id")
    @ManyToOne(optional = false, fetch = FetchType.LAZY)
    private User creator;

    @Basic(optional = false)
    @Column(name = "modified")
    @Temporal(TemporalType.TIMESTAMP)
    private Date modified = new Date();

    @Basic(optional = false)
    @Column(name = "late_submission")
    private boolean late_submission;

    @Basic(optional = false)
    @Column(name = "submission_visibility")
    private boolean submission_visibility;

    @JoinColumn(name="course", referencedColumnName = "id")
    @ManyToOne(optional=false, fetch = FetchType.LAZY)
    private Course course;

    @JoinTable(name = "assignment_target_group", joinColumns = {
        @JoinColumn(name = "assignment_id", referencedColumnName = "id")}, inverseJoinColumns = {
        @JoinColumn(name = "coursegroup_id", referencedColumnName = "id")})
    @ManyToMany
    private Collection<Coursegroup> target_group;

    @JoinTable(name = "assignment_learning_outcomes", joinColumns = {
        @JoinColumn(name = "assignment", referencedColumnName = "id")}, inverseJoinColumns = {
        @JoinColumn(name = "learningoutcome", referencedColumnName = "id")})
    @ManyToMany(cascade = {CascadeType.MERGE, CascadeType.PERSIST, CascadeType.REFRESH})
    private Set<LearningOutcome> learning_outcomes;

    @Transient
    @XmlElement(name="course-id")
    private Long courseId;

    @Transient
    @XmlElementWrapper(name="target-group")
    @XmlElement(name="group-id")
    public Collection<Long> groupIds;

    @OneToMany (mappedBy="assignment")
    @JoinTable(name = "answer",
        joinColumns = @JoinColumn(name = "assignment"),
        inverseJoinColumns = @JoinColumn(name = "id")
    )
    private Set<Answer> answers;

    @Transient
    @XmlElementWrapper(name="tags")
    @XmlElement(name="tag")
    public Collection<String> tags;

    @Transient
    @XmlElementWrapper(name="outcomes")
    @XmlElement(name="outcome")
    public Set<Long> outcomes;

    public Assignment() {
        answers = new HashSet<Answer>();
    }

    public Assignment(Long id) {
        this.id = id;
    }

    public Long getId() {
        return id;
    }

    public void setId(Long id) {
        this.id = id;
    }

    public String getType() {
        return type;
    }

    public void setType(String type) {
        this.type = type;
    }

    public String getTitle() {
        return title;
    }

    public void setTitle(String title) {
        this.title = title;
    }

    public String getDescription() {
        return description;
    }

    public void setDescription(String description) {
        this.description = description;
    }

    public int getStart() {
        return start;
    }

    public void setStart(int start) {
        this.start = start;
    }

    public boolean isSubmissionValid() {
        Calendar current_date = Utility.getCalendarInstance();

        //Init start date calendar
        Calendar start_date = Utility.getCalendarInstance( this.getStart() );
        //Init end date calendar
        Calendar end_date = Utility.getCalendarInstance( this.getEnd() );
        
        //First check, if assignemnt is available (start date) //let's assume somebody is trying to hack via assignment ID in WP
        if ( current_date.before(start_date) ) {
            return false;
        }
        
        //Second check end date value before or equal and late_submission flag
        if ( this.isLate_submission() || current_date.compareTo(end_date) <= 0 ) {
            return true;
        }
        return false;
    }
    
    public int getEnd() {
        return end;
    }

    public void setEnd(int end) {
        this.end = end;
    }

    public Date getCreated() {
        return created;
    }

    public void setCreated(Date created) {
        this.created = created;
    }

    public User getCreator() {
        return creator;
    }

    public void setCreator(User user) {
        this.creator = user;
    }

    public Date getModified() {
        return modified;
    }

    public void setModified(Date modified) {
        this.modified = modified;
    }

    public Collection<Coursegroup> getTargetGroup() {
        return target_group;
    }

    public void setTargetGroup(Collection<Coursegroup> target_group) {
        this.target_group = target_group;
    }

    public Course getCourse() {
        return course;
    }

    public void setCourse(Course course) {
        this.course = course;
        if ( !this.course.getAssignments().contains(this) ) {
            this.course.addAssignment(this);
        }
    }

    public Long getCourseId() {
        return courseId;
    }
    
    public Collection<Answer> getAnswers() {
        return answers;
    }
    
    public Answer getLearnerAnswer(Long user_id) {
        for( Answer a : getAnswers() ) {
            if ( a.getCreator().getId() == user_id ) {
                return a;
            }
        }
      return null;
    }

    public void setAnswers(Set<Answer> answers) {
        this.answers = answers;
    }
    
    public void addAnswer(Answer answer) {
        this.answers.add(answer);
        //Bi-directional assignment set 
        if ( answer.getAssignment() != this ) {
            answer.setAssignment(this);
        }
    }

    public Set<LearningOutcome> getLearning_outcomes() {
        return learning_outcomes;
    }

    public void setLearning_outcomes(Set<LearningOutcome> learning_outcomes) {
        this.learning_outcomes = learning_outcomes;
    }

    public void setTags(Collection<String> cts) {
        this.tags = cts;
    }

    public String getSubtype() {
        return subtype;
    }

    public void setSubtype(String subtype) {
        this.subtype = subtype;
    }


    public String getStructure() {
        return structure;
    }

    public void setStructure(String structure) {
        this.structure = structure;
    }

    public int getMaxpoints() {
        return maxpoints;
    }

    public void setMaxpoints(int maxpoints) {
        this.maxpoints = maxpoints;
    }

    public boolean isLate_submission() {
        return late_submission;
    }

    public void setLate_submission(boolean late_submission) {
        this.late_submission = late_submission;
    }

    public boolean isSubmission_visibility() {
        return submission_visibility;
    }

    public void setSubmission_visibility(boolean submission_visibility) {
        this.submission_visibility = submission_visibility;
    }

    @Override
    public int hashCode() {
        int hash = 0;
        hash += (id != null ? id.hashCode() : 0);
        return hash;
    }

    @Override
    public boolean equals(Object object) {
        // TODO: Warning - this method won't work in the case the id fields are not set
        if (!(object instanceof Assignment)) {
            return false;
        }
        Assignment other = (Assignment) object;
        if ((this.id == null && other.id != null) || (this.id != null && !this.id.equals(other.id))) {
            return false;
        }
        return true;
    }

    @Override
    public String toString() {
        return "ee.tlu.htk.dippler.entities.Assignment[id=" + id + "]";
    }

}