package group04;

import java.io.IOException;
import java.util.ArrayList;
import java.util.Iterator;

import group04.myBatis.Nodeinfo;

/**
 * basic node class of node, it can explane a single node and the level of node
 */
public class BasicNode implements Iterable<BasicNode>
{
    /**
     * <0 : invalidity node
     * =0 : undifineded node
     * >0 : created node
     */
    private long id = 0l;

    private BasicNode nextNode = null;
    private BasicNode pervNode = null;

    
    private BasicNode childLevel = null;
    private BasicNode parentNode = null;

    private static ArrayList<BasicNode> NeedUpload = new ArrayList<>();

    /**
     * create new node
     * @throws IOException no mapper
     */
    public BasicNode(){}

    /**
     * create node by confirm id
     * @param id node id
     * @throws IOException no mapper
     */
    public BasicNode(long id) throws IOException
    {
        setId(Math.abs(id));
    }

    
    @Override
    public NodeIterator iterator() {
        BasicNode node = startOfNodeLevel();
        return new NodeIterator(node);
    }

    /**
     * get node id
     * @return id of this node
     */
    public long getId() {
        return id;
    }

    /**
     * get next node of this node
     * @return next node
     */
    public BasicNode getNextNode()
    {
        return nextNode;
    }

    /**
     * get previous node of this node
     * @return previous node
     */
    public BasicNode getPervNode()
    {
        return pervNode;
    }

    /**
     * get parrent node of this node
     * @return parrent node
     */
    public BasicNode getParentNode()
    {
        return parentNode;
    }

    /**
     * get child level
     * @return first node of child nodes
     */
    public BasicNode getChildLevel()
    {
        if(childLevel != null)
        {
            while(childLevel.pervNode != null)
            {
                childLevel = childLevel.pervNode;
            }
        }
        return childLevel;
    }

    public void setNeedUpload()
    {
        synchronized(NeedUpload)
        {
            if(!NeedUpload.contains(this))
            {
                NeedUpload.add(this);
            }
        }
    }

    /**
     * set Node id,also it can destroy this node by seting id to minus value
     * @param id new id
     * @throws IOException no mapper
     */
    public void setId(long id) throws IOException
    {
        synchronized(this)
        {
            //defineded id
            if(id == 0 || !vaildity()) return;
            //not null
            if(id < 0)
            {
                //delete
                NodeDao.getCurrentMapper().deleteByPrimaryKey(this.id);
                //if database vaildity, it will going on.
                dropFromLevel();
                //delete all child nodes
                BasicNode node = this.getChildLevel();
                while(node != null)
                {
                    BasicNode next = node.getNextNode();
                    node.deleteNode();
                    node = next;
                }
            }
            else if(NodeDao.state() != NodeDao.DaoState.Reading)
            {
                Nodeinfo data = getNodeInfo();
    
                data.setId(id);
    
                try 
                {
                    //id is primary key of node info, we can't modify the primary key by primary key, so it need delete first
                    NodeDao.getCurrentMapper().insert(data);
                    //delete
                    if(defineded()) NodeDao.getCurrentMapper().deleteByPrimaryKey(this.id);
                }
                catch (IOException IOEx)
                {
                    //no mapper
                    throw IOEx;
                }
                catch (Exception e)
                {
                    //sql errery
                    return;
                }
            }
            else
            {
                InitAfterLoad(id);
            }
            this.id = id;
        }
    }

    /**
     * for override, invoke when load feom database
     * @param id currectt id information
     */
    private void InitAfterLoad(long id)
    {

    }

    /**
     * convert to NodeInfo data
     * @return Node info for sql upload
     */
    public Nodeinfo getNodeInfo()
    {
        //gen data for update database
        Nodeinfo data = new Nodeinfo();
        BasicNode node = null;
        //node id
        data.setId(getId());
        //next element
        node = getNextNode();
        if(node != null && node.vaildity())data.setNextId(node.getId());
        else data.setNextId(null);
        //perv element
        node = getPervNode();
        if(node != null && node.vaildity())data.setPrevId(node.getId());
        else data.setPrevId(null);
        //parent element
        node = getParentNode();
        if(node != null && node.vaildity())data.setParentId(node.getId());
        else data.setParentId(null);
        //chile level
        node = getChildLevel();
        if(node != null && node.vaildity())
        {
            node = node.startOfNodeLevel();
            data.setChildId(node.getId());
        }
        else data.setChildId(null);
        //node class
        data.setObjType(this.getClass().getName());
        return data;
    }

    /**
     * upload to database
     * @throws IOException no mapper
     */
    public void uploadNode() throws IOException
    {
        synchronized(this)
        {
            Nodeinfo data = getNodeInfo();
            NodeDao.getCurrentMapper().updateByPrimaryKey(data);
        }
    }

    /**
     * check node vaild
     * @return if is false it should not exists in database
     */
    public boolean vaildity()
    {
        if(getId() >= 0)
        {
            for (BasicNode basicNode : NeedUpload) {
                if(this.equals(basicNode) && basicNode != this) return false;
            }
            return true;
        }
        return false;
    }

    /**
     * check id defined statue
     * @return if is true, node id should defineded
     */
    public boolean defineded()
    {
        return vaildity() && getId() > 0;
    }

    /**
     * InnerHTML of tab
     * @return DOM Context.InnerHTML
     */
    public String tabContextInnerHTML()
    {
        return "id : " + getId();
    }

    /**
     * remove itselfs from its level
     */
    public void dropFromLevel()
    {
        synchronized(this)
        {
            if(this.nextNode != null)
            {
                this.nextNode.pervNode = this.pervNode;
                this.nextNode.setNeedUpload();
                
            }
            if(this.pervNode != null)
            {
                this.pervNode.nextNode = this.nextNode;
                this.pervNode.setNeedUpload();
            }
            else
            if(this.parentNode != null)
            {
                this.parentNode.childLevel = this.nextNode;
                this.parentNode.setNeedUpload();
            }
            this.parentNode = null;
            this.nextNode = null;
            this.pervNode = null;
            this.setNeedUpload();
        }
    }
    
    /**
     * instert a {@link #node} after this node
     * @param node node to instert/
     */
    public boolean insertNext(BasicNode node)
    {
        synchronized(this)
        {
            if(node != null && node.vaildity() && this.vaildity())
            {
                if(!node.subTreeContains(this))
                {
                    //remove from its level
                    node.dropFromLevel();
                    //cache
                    BasicNode nextNode = this.nextNode;
                    //replace next
                    this.nextNode = node;
                    node.nextNode = nextNode;
                    //replace perv
                    node.pervNode = this;
                    //set to same parent node
                    node.parentNode = this.parentNode;
                    //check if exiet
                    if(nextNode != null)
                    {
                        nextNode.pervNode = node;
                        nextNode.setNeedUpload();
                    }
    
                    this.setNeedUpload();
                    return true;
                }
            }
            return false;
        }
    }

    /**
     * instert a {@link #node} before this node
     * @param node node to instert
     */
    public boolean insertPerv(BasicNode node)
    {
        synchronized(this)
        {
            if(node != null && node.vaildity() && this.vaildity())
            {
                if(!node.subTreeContains(this))
                {
                    //remove from its level
                    node.dropFromLevel();
                    //cache
                    BasicNode pervNode = this.pervNode;
                    //replace next
                    this.pervNode = node;
                    node.pervNode = pervNode;
                    //replace last
                    node.nextNode = this;
                    //set to same parent node
                    node.parentNode = this.parentNode;
                    //check if exiet
                    if(pervNode != null)
                    {
                        pervNode.nextNode = node;
                        pervNode.setNeedUpload();
                    }
                    else //remove if parrentNode exiet
                    if(this.parentNode != null)
                    {
                        this.parentNode.childLevel = node;
                        this.parentNode.setNeedUpload();
                    }
    
                    this.setNeedUpload();
                    return true;
                }
            }
            return false;
        }
    }

    /**
     * replace current pos of its level
     * @param node node for replace
     */
    public boolean replaceBy(BasicNode node)
    {
        synchronized(this)
        {
            if(!vaildity()) return false;
            if(node != null && node.vaildity())
            {
                if(!node.subTreeContains(this))
                {                
                    node.dropFromLevel();
                    node.parentNode = this.parentNode;
                    node.nextNode = this.nextNode;
                    node.pervNode = this.pervNode;
                    this.dropFromLevel();
                    if(node.nextNode != null)
                    {
                        node.nextNode.pervNode = node;
                    }
                    if(node.pervNode != null)
                    {
                        node.pervNode.nextNode = node;
                    }
                    else
                    if(node.parentNode != null)
                    {
                        node.parentNode.childLevel = node;
                        node.parentNode.setNeedUpload();
                    }
                    return true;
                }
            }
            else
            {
                this.dropFromLevel();
                return true;
            }
            return false;
        }
    }


    public boolean exchangeWith(BasicNode node)
    {
        synchronized(this)
        {
            if(!vaildity()) return false;
            if(node != null && node.vaildity())
            {
                if(!node.subTreeContains(this) && !this.subTreeContains(node))
                {
                    //cache
                    BasicNode next = node.nextNode;
                    BasicNode perv = node.pervNode;
                    BasicNode parent = node.parentNode;
                    
                    if(next == this)
                    {
                        next = this.pervNode;
                        this.pervNode = this;
                    }
                    if(perv == this)
                    {
                        perv = this.nextNode;
                        this.nextNode = this;
                    }
                    //set node to this
                    node.nextNode = this.nextNode;
                    node.pervNode = this.pervNode;
                    node.parentNode = this.parentNode;
                    node.setNeedUpload();
                    //check near by node update
                    if(node.nextNode != null)
                    {
                        node.nextNode.pervNode = node;
                        node.nextNode.setNeedUpload();
                    }
                    if(node.pervNode != null)
                    {
                        node.pervNode.nextNode = node;
                        node.pervNode.setNeedUpload();
                    }
                    else
                    if(node.parentNode != null)
                    {
                        node.parentNode.childLevel = node;
                        node.parentNode.setNeedUpload();
                    }
    
                    //set this to next
                    this.nextNode = next;
                    this.pervNode = perv;
                    this.parentNode = parent;
                    this.setNeedUpload();
                    //check near by node update
                    if(this.nextNode != null)
                    {
                        this.nextNode.pervNode = this;
                        this.nextNode.setNeedUpload();
                    }
                    if(this.pervNode != null)
                    {
                        this.pervNode.nextNode = this;
                        this.pervNode.setNeedUpload();
                    }
                    else
                    if(this.parentNode != null)
                    {
                        this.parentNode.childLevel = this;
                        this.parentNode.setNeedUpload();
                    }
                    return true;
                }
            }
            else
            {
                this.dropFromLevel();
                return true;
            }
            return false;
        }
    }
    
    /**
     * Level's start
     */
    public BasicNode startOfNodeLevel()
    {
        BasicNode node = this;
        while(node.pervNode != null)
        {
            node = node.pervNode;
        }
        return node;
    }
    
    /**
     * Level's end
     */
    public BasicNode endOfNodeLevel()
    {
        BasicNode node = this;
        while(node.nextNode != null)
        {
            node = node.nextNode;
        }
        return node;
    }
    
    /**
     * get root of node tree
     * @return node of the minimum level
     */
    public BasicNode rootNode()
    {
        BasicNode node = this;
        while(node.parentNode != null)
        {
            node = node.parentNode;
        }
        return node;
    }

    /**
     * replace child level to {@link #childLevel}
     * @param childLevel target
     * @return if success , return droped node else null
     */
    public BasicNode setChildLevel(BasicNode childLevel)
    {
        //is use as level, so we need to 
        if(childLevel != null && vaildity() && childLevel.vaildity())
        {
            //save usage
            childLevel = childLevel.startOfNodeLevel();
            if(childLevel.subTreeContains(this.startOfNodeLevel())) return null;
            BasicNode result = this.childLevel;
            if(childLevel != null)
            {
                for(BasicNode node : childLevel)
                {
                    node.parentNode = this;
                }
            }
            if(this.childLevel != null)
            {
                for(BasicNode node : this.childLevel)
                {
                    node.parentNode = null;
                }
            }
            this.childLevel = childLevel;
            return result;
        }
        return null;
    }

    /**
     * check if level contains {@ling #node}
     * @param node node for check
     * @return {@value true} mean contains {@value false} mean not contains
     */
    public boolean levelContains(BasicNode node)
    {
        if(node != null)
        {
            if(node.parentNode != null && this.parentNode != null)
            {
                return node.parentNode == this.parentNode;
            }
            else
            {
                BasicNode cache1 = node;
                BasicNode cache2 = this;
                do
                {
                    //check 2 node's perv node at same time
                    if(cache1.equals(this) || cache2.equals(node))
                        return true;
                    if(cache1.pervNode != null)
                        cache1 = cache1.pervNode;
                    if(cache2.pervNode != null)
                        cache2 = cache2.pervNode;
                }
                while(cache2.pervNode != null || cache1.pervNode != null);
                return cache1 == cache2;
            }
        }
        return false;
    }

    /**
     * check if node tree has node
     * @param node node for check
     * @return {@value true} mean contains {@value false} mean not contains
     */
    public boolean treeContains(BasicNode node)
    {
        if(node != null)
        {
            return node.rootNode().levelContains(this.rootNode());
        }
        return false;
    }

    /**
     * check if this node is a sub node of the node
     * @param node node for check
     * @return if this node is a sub node of the node, it will return true 
     */
    public boolean subTreeContains(BasicNode node)
    {
        if(node != null)
        {
            do
            {
                if(node.equals(this))
                {
                    return true;
                }
                node = node.parentNode;
            }
            while(node != null);
        }
        return false;
    }


    public long getLayout()
    {
        long result = 0;
        BasicNode node =this.getParentNode();
        while(node != null)
        {
            node = node.getParentNode();
            ++result;
        }
        return result;
    }
    

    @Override
    public String toString() 
    {
        String result = this.getId() + "{ ";
        for(BasicNode node : this)
        {
            result += node.getId();
            if(node.getChildLevel() != null) result += "+";
            if(node.nextNode != null) result += " , ";
        }
        return result + " }";
    }

    public void deleteNode() throws IOException
    {
        this.setId(-1l);
    }

    /**
     * check level
     * @param levelA value a
     * @param levelB value b
     * @return if is same level,it will return true
     */
    public static boolean levelEqul(BasicNode levelA,BasicNode levelB)
    {
        return levelA.startOfNodeLevel().id == levelB.startOfNodeLevel().id;
    }

    @Override
    public boolean equals(Object o) {
        // TODO Auto-generated method stub
        BasicNode other = (BasicNode)o;
        if(other != null) return other.id == this.id;
        else return super.equals(o);
    }

    /**
     * check all loaded node and upload data
     * @throws IOException no sql mapper
     */
    public static void Commit() throws IOException
    {
        synchronized(NeedUpload)
        {
            for (BasicNode basicNode : NeedUpload)
            {
                basicNode.uploadNode();
            }
            NodeDao.getCurrentMapper().commit();
            NeedUpload.clear();
        }
    }


    public static BasicNode TryGetNotCommitNodeById(long id)
    {
        synchronized(NeedUpload)
        {
            for (BasicNode basicNode : NeedUpload)
            {
                if(basicNode.getId() == id)
                {
                    return basicNode;
                }
            }
            return null;
        }
    }

    /**
     * Iterator of {@link #BasicNode}
     */
    class NodeIterator implements Iterator<BasicNode>
    {
        BasicNode next;
        private NodeIterator(BasicNode node)
        {
            next = node;
        }

        @Override
        public boolean hasNext() {
            return next != null;
        }
        
        @Override
        public BasicNode next() {
            BasicNode next = this.next;
            this.next = next.nextNode;
            return next;
        }
    }

}