package writer2latex.xhtml.content;

import java.util.Iterator;
import java.util.LinkedList;

import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;

import pro.litvinovg.xml.Debug;
import writer2latex.office.XMLString;
import writer2latex.xhtml.Converter;
import writer2latex.xhtml.XhtmlConfig;

import static writer2latex.util.Misc.*;

//LinkedList<String>   stringList = new LinkedList<String>();
public class Separator {

	private static final String NONE = "none";
	private static final String SECTIONS = "sections";
	private static final String DIV = "div";
	private int splitLevel = 0;
	private boolean alignSplitToPages;
	private int lastSplitPageNum = 1;
	private Integer pageNumber = null;
	private String breakStyle = null;

	private static LinkedList<Integer> greenstoneStack = new LinkedList<Integer>();
	private int[] headingPath;
	private static boolean pageOpened = false;
	// headings none
	private static boolean greenstoneSeparation;
	private static boolean rdfSeparation = false;
	// sections div none
	private static boolean pagination;
	private static Converter converter = null;
	private Node prevPageContainer = null;
	private PageContainer pageContainer = null;

	public Separator(XhtmlConfig config, Converter converter) {
		this.converter = converter;
		greenstoneSeparation = config.getGreenstoneSeparation();
		pagination = config.pagination();
		splitLevel = config.getXhtmlSplitLevel();
		alignSplitToPages = config.getAlignSplitsToPages();
		breakStyle = config.getPageBreakStyle();
		pageContainer = converter.pageContainer;
		rdfSeparation = converter.isRDF;
		headingPath = new int[10];
	}

	public Node processOutlineLevel(Node currentNode, Node hnode, int pageNum) {

		// Get outline level
		String sLevel = getAttribute(currentNode, XMLString.TEXT_OUTLINE_LEVEL);
		// System.out.println(sLevel);
		if (sLevel == null || sLevel.isEmpty()) {
			return hnode;
		}
		String title = getTitle(currentNode).trim();
		if (title == null || title.isEmpty()) {
			return hnode;
		}
		// System.out.println(sLevel + "after title");

		int curLevel = Integer.parseInt(sLevel);

		
		if (noSplitNeeded(pageNum, curLevel)) { 
			 System.out.println(sLevel + "no split needed");

			return hnode;
		}
		 
		if (isSplitTime(curLevel, pageNum)) {
			prevPageContainer = hnode;
		}

		if (pageOpened) {
			hnode = closePage(hnode);
		}

		if (greenstoneSeparation) {
			closeCommentHeadings(hnode, curLevel);
		}

		updateHeadingPath(curLevel);

		if (isSplitTime(curLevel, pageNum)) {
			hnode = splitFiles(hnode);
			lastSplitPageNum = pageNum;
		}
		if (greenstoneSeparation) {
			openCommentHeading(hnode, title);
			addToCommentStack(sLevel);
		}

		if (pagination) {
			hnode = openPage(hnode, pageNum);
		}

		return hnode;
	}

	private boolean noSplitNeeded(int pageNum, int curLevel) {
		return !greenstoneSeparation && !isSplitTime(curLevel,pageNum);
	}

	private void addToCommentStack(String sLevel) {
		greenstoneStack.offerFirst(Integer.parseInt(sLevel));
	}

	private void updateHeadingPath(int level) {
		if (level == 0) {
			return;
		}
		for (int i = 9; i > level - 1; i--) {
			headingPath[i] = 0;
		}
		headingPath[level - 1]++;
	}

	private Node splitFiles(Node hnode) {
		String path = "";
		for (int i = 0; i < 10; i++) {
			path = path + " " + headingPath[i];
		}
		hnode = converter.nextOutFile();
		((Element) hnode).setAttribute("path", path.trim());
		return hnode;
	}

	private boolean isSplitTime(int curLevel, int pageNum) {
		if ((rdfSeparation || splitLevel >= curLevel ) && converter.outFileHasContent()) {
			if (alignSplitToPages) {
				if (lastSplitPageNum != pageNum) {
					return true;
				}	
			} else {
				return true;
			}
		}
		return false;
	}

	public Node processPageBreak(Node currentNode, Node hnode, Integer pageNum) {
		if (!pagination) {
			return hnode;
		}
		if (pageOpened) {
			hnode = closePage(hnode);
		}
		hnode = openPage(hnode, pageNum);

		return hnode;
	}

	public boolean isPageOpened() {
		return pageOpened;
	}

	/**
	 * Opens main document section heading tag
	 */
	public Node startDocument(Node hnode, String title, int pageNum) {
		if (!greenstoneSeparation && !pagination) {
			return hnode;
		}
		if (greenstoneSeparation) {
			// Create global section
			openCommentHeading(hnode, title);
		}
		hnode = openPage(hnode, pageNum);

		return hnode;
	}

	// Method to close open tags at the end of the document
	public Node endDocument(Node hnode) {
		if (!greenstoneSeparation && !pagination) {
			return hnode;
		}
		if (pageOpened) {
			hnode = closePage(hnode);
		}
		if (greenstoneSeparation) {
			closeCommentHeadings(hnode, 0);
			// Close global section
			addCloseComment(hnode);
		}

		return hnode;
	}

	private Node openPageDiv(Node node, int curPageNum) {
		if (node == null) {
			System.out.println("Error: node is null on openPageDiv");
			return node;
		}
		if (prevPageContainer != null && alignSplitToPages) {
			alignFilesByHeadings(node, curPageNum);
		}
		breakPage(node, curPageNum);
		Document doc = node.getOwnerDocument();
		Element openBlock = (Element) doc.createElement(DIV);
		openBlock.setAttribute("class", "pageNum");
		openBlock.setAttribute("page", Integer.toString(curPageNum));
		// insert open section comment before header node
		node.appendChild((Node) openBlock);
		node = openBlock;
		return openBlock;
	}

	private void breakPage(Node node, int curPageNum) {
		if (pageNumber != null && pageNumber != curPageNum) {
			Document doc = node.getOwnerDocument();
			Element pageBreak = (Element) doc.createElement(DIV);
			pageBreak.setAttribute("class", "pageBreak");
			if (breakStyleIsSet()) {
				applyBreakStyle(pageBreak);
			}
			node.appendChild(pageBreak);
		}
		pageNumber = curPageNum;
	}

	private void applyBreakStyle(Element pageBreak) {
		pageBreak.setAttribute("style", breakStyle);
	}

	public boolean breakStyleIsSet() {
		if (breakStyle == null || breakStyle.isEmpty()) {
			return false;
		} else {
			return true;
		}
	}

	private void alignFilesByHeadings(Node node, int pageNum) {
		Document newdoc = node.getOwnerDocument();
		Node prevPage = prevPageContainer.getParentNode();
		String prevPageNum = getAttribute(prevPage, "page");
		if (prevPageNum != null && prevPageNum.equals(Integer.toString(pageNum))) {
			if (isElement(prevPage, DIV)) {
				Node importedNode = newdoc.importNode(prevPage, true);
				node.appendChild(importedNode);
				Node prevDoc = prevPage.getParentNode();
				if (prevDoc != null) {
					prevDoc.removeChild(prevPage);
				}
			}
		}
		// no more arrange needed till next file separation
		prevPageContainer = null;

	}

	private static Node exitPageDiv(Node node) {

		while (!isRoot(node) && !isElement(node, DIV)) {
			node = node.getParentNode();
		}
		Node result = node.getParentNode();
		if (node.getChildNodes().getLength() == 1) {
			if (node.getFirstChild().getChildNodes().getLength() == 0) {
				result.removeChild(node);
			}
		}

		return result;
	}

	public static String getTitle(Node currentNode) {
		Node content = currentNode.cloneNode(true);
		String title = null;
		NodeList lineBreaks = ((Element) content).getElementsByTagName(XMLString.TEXT_LINE_BREAK);
		NodeList textTabs = ((Element) content).getElementsByTagName(XMLString.TEXT_TAB);

		replaceWithSpaces(lineBreaks);
		replaceWithSpaces(textTabs);
		deleteNotesIn(content);
		title = content.getTextContent();
		return title;
	}

	private static void deleteNotesIn(Node content) {
		NodeList notes = ((Element) content).getElementsByTagName(XMLString.TEXT_NOTE);
		int j = 0;
		while (j < notes.getLength()) {
			Node note = notes.item(j);
			note.getParentNode().removeChild(note);
		}
	}

	private static void replaceWithSpaces(NodeList contentNodes) {
		int i = 0;
		while (i < contentNodes.getLength()) {
			Node node = contentNodes.item(i);
			Document doc = node.getOwnerDocument();
			Node testSpace = doc.createTextNode(" ");
			node.getParentNode().insertBefore(testSpace, node);
			node.getParentNode().removeChild(node);
			i++;
		}
	}

	private static void openCommentHeading(Node hnode, String title) {
		Document doc = hnode.getOwnerDocument();
		Node openSection = doc.createComment(openHeadingCommentText(title));
		// insert open section comment before header node
		hnode.appendChild(openSection);
	}

	private static void addCloseComment(Node node) {
		Document doc = node.getOwnerDocument();
		Node closeSection = doc.createComment("</Section>");
		// insert open section comment before header node
		node.appendChild(closeSection);
	}

	private static void closeCommentHeadings(Node hnode, int nLevel) {
		if (greenstoneStack.isEmpty()) {
			return;
		}
		// Close all sections with level less than current
		while (nLevel <= greenstoneStack.peek()) {
			addCloseComment(hnode);
			greenstoneStack.poll();
			if (greenstoneStack.isEmpty()) {
				break;
			}
		}
	}

	public Node closePage(Node hnode) {
		if (pageOpened == false) {
			return hnode;
		}
		hnode = exitPageContainer(hnode);
		if (pagination) {
			hnode = exitPageDiv(hnode);
		}
		pageOpened = false;
		return hnode;
	}

	public Node openPage(Node hnode, Integer pageNum) {
		if (pageOpened == true || !pagination) {
			return hnode;
		}
		hnode = openPageDiv(hnode, pageNum);
		pageOpened = true;
		hnode = enterPageContainer(hnode);
		return hnode;
	}

	private Node exitPageContainer(Node hnode) {
		String className = ((Element) hnode).getAttribute("class");
		if (!className.equals("pageContainer")) {
			System.out.println("Can't exit not my container!");
			Debug.printNode(hnode);
			Debug.printStackTrace();
			System.exit(1);
		}
		Element parentNode = (Element) hnode.getParentNode();
		return parentNode;
	}

	private Node enterPageContainer(Node hnode) {
		if (hnode == null) {
			System.out.println("Enter page container error. hnode is null");
			Debug.printStackTrace();
			System.exit(1);
		}
		Element container = converter.createElement("div");
		container.setAttribute("class", "pageContainer");
		if (!pageContainer.getCurrentStyle().isEmpty()) {
			container.setAttribute("style", pageContainer.getCurrentStyle());
		}
		hnode.appendChild(container);
		return container;
	}

	private static String openHeadingCommentText(String title) {
		String comment = "<Section>\n<Description>\n<Metadata name=\"Title\">" + title + "</Metadata>\n</Description>";
		return comment;
	}

	private static String openPageCommentText(Integer pageNum) {
		String comment = "<Section>\n<Description>\n<Metadata name=\"Title\">" + pageNum + "</Metadata>\n<Metadata name=\"Page\">" + pageNum + "</Metadata>\n</Description>";
		return comment;
	}

}