sascha@372: package de.intevation.flys.artifacts.services.meta;
sascha@372: 
sascha@972: import java.util.regex.Pattern;
sascha@372: import java.util.regex.Matcher;
sascha@372: 
sascha@372: import java.util.ArrayList;
sascha@372: import java.util.List;
sascha@372: import java.util.HashMap;
sascha@372: import java.util.Map;
sascha@372: 
sascha@372: import org.w3c.dom.Document;
sascha@372: import org.w3c.dom.NodeList;
sascha@372: import org.w3c.dom.Node;
sascha@372: import org.w3c.dom.Element;
sascha@372: 
sascha@957: import javax.xml.xpath.XPath;
sascha@957: import javax.xml.xpath.XPathFactory;
sascha@957: import javax.xml.xpath.XPathExpressionException;
sascha@957: import javax.xml.xpath.XPathConstants;
sascha@957: 
sascha@372: import java.sql.SQLException;
sascha@372: import java.sql.Connection;
sascha@372: 
sascha@372: import de.intevation.artifacts.common.utils.XMLUtils;
sascha@372: 
sascha@372: import org.apache.log4j.Logger;
sascha@372: 
sascha@372: public class Builder
sascha@372: {
sascha@372:     private static Logger log = Logger.getLogger(Builder.class);
sascha@372: 
sascha@972:     public static final Pattern STRIP_LINE_INDENT =
sascha@972:         Pattern.compile("\\s*\\r?\\n\\s*");
sascha@972: 
sascha@372:     public static final String DC_NAMESPACE_URI =
sascha@372:         "http://www.intevation.org/2011/Datacage";
sascha@372: 
sascha@957:     private static final Document EVAL_DOCUMENT =
sascha@957:         XMLUtils.newDocument();
sascha@957: 
sascha@957:     private static final XPathFactory XPATH_FACTORY =
sascha@957:         XPathFactory.newInstance();
sascha@957: 
sascha@415:     protected Document template;
sascha@372: 
sascha@973:     protected Map<String, CompiledStatement> compiledStatements;
sascha@973: 
sascha@963: 
sascha@372:     public class BuildHelper
sascha@372:     {
sascha@973:         protected Node                                    output;
sascha@973:         protected Document                                owner;
sascha@973:         protected StackFrames                             frames;
sascha@973:         protected Connection                              connection;
sascha@973:         protected Map<String, CompiledStatement.Instance> statements;
sascha@372: 
sascha@415:         public BuildHelper(
sascha@963:             Node                output,
sascha@415:             Connection          connection,
sascha@415:             Map<String, Object> parameters
sascha@415:         ) {
sascha@372:             this.output     = output;
sascha@372:             this.connection = connection;
sascha@415:             frames          = new StackFrames(parameters);
sascha@973:             statements      = new HashMap<String, CompiledStatement.Instance>();
sascha@963:             owner           = getOwnerDocument(output);
sascha@372:         }
sascha@372: 
sascha@372:         public void build(List<Node> elements) throws SQLException {
sascha@372:             try {
sascha@372:                 for (Node current: elements) {
sascha@372:                     build(output, current);
sascha@372:                 }
sascha@372:             }
sascha@372:             finally {
sascha@973:                 closeStatements();
sascha@372:             }
sascha@372:         }
sascha@372: 
sascha@973:         protected void closeStatements() {
sascha@973:             for (CompiledStatement.Instance csi: statements.values()) {
sascha@973:                 csi.close();
sascha@973:             }
sascha@973:             statements.clear();
sascha@973:         }
sascha@973: 
sascha@372:         protected void context(Node parent, Element current)
sascha@372:         throws SQLException
sascha@372:         {
sascha@372:             NodeList elements = current.getElementsByTagNameNS(
sascha@372:                 DC_NAMESPACE_URI, "elements");
sascha@372: 
sascha@372:             if (elements.getLength() < 1) {
sascha@372:                 log.warn("no elements found -> ignore");
sascha@372:                 return;
sascha@372:             }
sascha@372: 
sascha@372:             NodeList subs = elements.item(0).getChildNodes();
sascha@372:             int S = subs.getLength();
sascha@372: 
sascha@372:             if (S < 1) {
sascha@372:                 log.warn("elements is empty -> ignore");
sascha@372:                 return;
sascha@372:             }
sascha@372: 
sascha@372:             NodeList stmntNode = current.getElementsByTagNameNS(
sascha@372:                 DC_NAMESPACE_URI, "statement");
sascha@372: 
sascha@372:             if (stmntNode.getLength() < 1) {
sascha@372:                 log.warn("dc:context: too less statements");
sascha@372:                 return;
sascha@372:             }
sascha@372: 
sascha@372:             String stmntText = stmntNode.item(0).getTextContent();
sascha@372: 
sascha@973:             CompiledStatement.Instance csi = statements.get(stmntText);
sascha@973: 
sascha@973:             if (csi == null) {
sascha@973:                 CompiledStatement cs = compiledStatements.get(stmntText);
sascha@973:                 csi = cs.new Instance();
sascha@973:                 statements.put(stmntText, csi);
sascha@372:             }
sascha@372: 
sascha@973:             ResultData rd = csi.execute(connection, frames);
sascha@372: 
sascha@372:             String [] columns = rd.getColumnLabels();
sascha@372: 
sascha@372: 
sascha@372:             for (Object [] row: rd.getRows()) {
sascha@372:                 frames.enter();
sascha@372:                 try {
sascha@372:                     frames.put(columns, row);
sascha@372:                     for (int i = 0; i < S; ++i) {
sascha@372:                         build(parent, subs.item(i));
sascha@372:                     }
sascha@372:                 }
sascha@372:                 finally {
sascha@372:                     frames.leave();
sascha@372:                 }
sascha@372:             }
sascha@372:         }
sascha@372: 
sascha@372:         protected void element(Node parent, Element current)
sascha@372:         throws SQLException
sascha@372:         {
sascha@372:             String attr = expand(current.getAttribute("name"));
sascha@372: 
sascha@372:             if (log.isDebugEnabled()) {
sascha@372:                 log.debug("dc:element -> '" + attr + "'");
sascha@372:             }
sascha@372: 
sascha@372:             if (attr.length() == 0) {
sascha@372:                 log.warn("no name attribute found");
sascha@372:                 return;
sascha@372:             }
sascha@372: 
sascha@963:             Element element = owner.createElement(attr);
sascha@372: 
sascha@372:             NodeList children = current.getChildNodes();
sascha@372:             for (int i = 0, N = children.getLength(); i < N; ++i) {
sascha@372:                 build(element, children.item(i));
sascha@372:             }
sascha@372: 
sascha@372:             parent.appendChild(element);
sascha@372:         }
sascha@372: 
sascha@372:         protected void text(Node parent, Element current)
sascha@372:         throws SQLException
sascha@372:         {
sascha@372:             log.debug("dc:text");
sascha@372:             String value = expand(current.getTextContent());
sascha@963:             parent.appendChild(owner.createTextNode(value));
sascha@372:         }
sascha@372: 
sascha@372: 
sascha@372:         protected void attribute(Node parent, Element current) {
sascha@372: 
sascha@372:             if (parent.getNodeType() != Node.ELEMENT_NODE) {
sascha@372:                 log.warn("need element here");
sascha@372:                 return;
sascha@372:             }
sascha@372: 
sascha@372:             String name  = expand(current.getAttribute("name"));
sascha@372:             String value = expand(current.getAttribute("value"));
sascha@372: 
sascha@372:             Element element = (Element)parent;
sascha@372: 
sascha@372:             element.setAttribute(name, value);
sascha@372:         }
sascha@372: 
sascha@962:         protected void callMacro(Node parent, Element current)
sascha@962:         throws SQLException
sascha@962:         {
sascha@962:             String name = current.getAttribute("name");
sascha@962: 
sascha@962:             if (name.length() == 0) {
sascha@962:                 log.warn("missing 'name' attribute in 'call-macro'");
sascha@962:                 return;
sascha@962:             }
sascha@962: 
sascha@962:             NodeList macros = template.getElementsByTagNameNS(
sascha@962:                 DC_NAMESPACE_URI, "macro");
sascha@962: 
sascha@962:             for (int i = 0, N = macros.getLength(); i < N; ++i) {
sascha@962:                 Element macro = (Element)macros.item(i);
sascha@962:                 if (name.equals(macro.getAttribute("name"))) {
sascha@962:                     NodeList subs = macro.getChildNodes();
sascha@962:                     for (int j = 0, M = subs.getLength(); j < M; ++j) {
sascha@962:                         build(parent, subs.item(j));
sascha@962:                     }
sascha@962:                     return;
sascha@962:                 }
sascha@962:             }
sascha@962: 
sascha@962:             log.warn("no macro '" + name + "' found.");
sascha@962:         }
sascha@962: 
sascha@961:         protected void ifClause(Node parent, Element current)
sascha@961:         throws SQLException
sascha@961:         {
sascha@961:             String test = current.getAttribute("test");
sascha@961: 
sascha@961:             if (test.length() == 0) {
sascha@961:                 log.warn("missing 'test' attribute in 'if'");
sascha@961:                 return;
sascha@961:             }
sascha@961: 
sascha@961:             Boolean result = evaluateXPath(test);
sascha@961: 
sascha@961:             if (result != null && result.booleanValue()) {
sascha@961:                 NodeList subs = current.getChildNodes();
sascha@961:                 for (int i = 0, N = subs.getLength(); i < N; ++i) {
sascha@961:                     build(parent, subs.item(i));
sascha@961:                 }
sascha@961:             }
sascha@961:         }
sascha@961: 
sascha@957:         protected void choose(Node parent, Element current)
sascha@957:         throws SQLException
sascha@957:         {
sascha@957:             Node branch = null;
sascha@957: 
sascha@957:             NodeList children = current.getChildNodes();
sascha@957:             for (int i = 0, N = children.getLength(); i < N; ++i) {
sascha@957:                 Node child = children.item(i);
sascha@957:                 String ns = child.getNamespaceURI();
sascha@957:                 if (ns == null
sascha@957:                 || !ns.equals(DC_NAMESPACE_URI)
sascha@957:                 || child.getNodeType() != Node.ELEMENT_NODE
sascha@957:                 ) {
sascha@957:                     continue;
sascha@957:                 }
sascha@957:                 String name = child.getLocalName();
sascha@957:                 if ("when".equals(name)) {
sascha@957:                     Element when = (Element)child;
sascha@957:                     String test = when.getAttribute("test");
sascha@957:                     if (test.length() == 0) {
sascha@957:                         log.warn("no 'test' attribute found for when");
sascha@957:                         continue;
sascha@957:                     }
sascha@957: 
sascha@959:                     Boolean result = evaluateXPath(test);
sascha@959:                     if (result != null && result.booleanValue()) {
sascha@959:                         branch = child;
sascha@959:                         break;
sascha@959:                     }
sascha@957: 
sascha@957:                     continue;
sascha@957:                 }
sascha@957:                 else if ("otherwise".equals(name)) {
sascha@957:                     branch = child;
sascha@957:                     // No break here.
sascha@957:                 }
sascha@957:             }
sascha@957: 
sascha@957:             if (branch != null) {
sascha@957:                 NodeList subs = branch.getChildNodes();
sascha@957:                 for (int i = 0, N = subs.getLength(); i < N; ++i) {
sascha@957:                     build(parent, subs.item(i));
sascha@957:                 }
sascha@957:             }
sascha@957:         }
sascha@957: 
sascha@959:         protected Boolean evaluateXPath(String expr) {
sascha@976: 
sascha@976:             if (log.isDebugEnabled()) {
sascha@976:                 log.debug("evaluate: '" + expr + "'");
sascha@976:             }
sascha@976: 
sascha@959:             try {
sascha@959:                 XPath xpath = XPATH_FACTORY.newXPath();
sascha@959:                 xpath.setXPathVariableResolver(frames);
sascha@959:                 xpath.setXPathFunctionResolver(FunctionResolver.FUNCTIONS);
sascha@959:                 Object result = xpath.evaluate(
sascha@959:                     expr, EVAL_DOCUMENT, XPathConstants.BOOLEAN);
sascha@959: 
sascha@959:                 return result instanceof Boolean
sascha@959:                     ? (Boolean)result
sascha@959:                     : null;
sascha@959:             }
sascha@959:             catch (XPathExpressionException xfce) {
sascha@959:                 log.error(xfce);
sascha@959:             }
sascha@959:             return null;
sascha@959:         }
sascha@959: 
sascha@415:         protected void convert(Node parent, Element current) {
sascha@415: 
sascha@415:             String variable = expand(current.getAttribute("var"));
sascha@415:             String type     = expand(current.getAttribute("type"));
sascha@415: 
sascha@415:             if (frames.containsKey(variable)) {
sascha@415:                 Object object = TypeConverter.convert(
sascha@415:                     frames.get(variable),
sascha@415:                     type);
sascha@415:                 frames.put(variable, object);
sascha@415:             }
sascha@415:         }
sascha@415: 
sascha@372:         protected String expand(String s) {
sascha@372:             Matcher m = CompiledStatement.VAR.matcher(s);
sascha@372: 
sascha@372:             StringBuffer sb = new StringBuffer();
sascha@372:             while (m.find()) {
sascha@372:                 String key = m.group(1);
sascha@372:                 Object value = frames.get(key);
sascha@372:                 m.appendReplacement(sb, value != null ? value.toString() : "");
sascha@372:             }
sascha@372:             m.appendTail(sb);
sascha@372:             return sb.toString();
sascha@372:         }
sascha@372: 
sascha@742:         protected void build(Node parent, Node current)
sascha@372:         throws SQLException
sascha@372:         {
sascha@372:             String ns = current.getNamespaceURI();
sascha@372:             if (ns != null && ns.equals(DC_NAMESPACE_URI)) {
sascha@372:                 if (current.getNodeType() != Node.ELEMENT_NODE) {
sascha@372:                     log.warn("need elements here");
sascha@372:                 }
sascha@372:                 else {
sascha@372:                     String localName = current.getLocalName();
sascha@972:                     if ("attribute".equals(localName)) {
sascha@972:                         attribute(parent, (Element)current);
sascha@972:                     }
sascha@972:                     else if ("context".equals(localName)) {
sascha@372:                         context(parent, (Element)current);
sascha@372:                     }
sascha@972:                     else if ("if".equals(localName)) {
sascha@972:                         ifClause(parent, (Element)current);
sascha@972:                     }
sascha@957:                     else if ("choose".equals(localName)) {
sascha@957:                         choose(parent, (Element)current);
sascha@957:                     }
sascha@972:                     else if ("call-macro".equals(localName)) {
sascha@972:                         callMacro(parent, (Element)current);
sascha@961:                     }
sascha@972:                     else if ("macro".equals(localName)) {
sascha@972:                         // simply ignore the definition.
sascha@372:                     }
sascha@372:                     else if ("element".equals(localName)) {
sascha@372:                         element(parent, (Element)current);
sascha@372:                     }
sascha@372:                     else if ("text".equals(localName)) {
sascha@372:                         text(parent, (Element)current);
sascha@372:                     }
sascha@415:                     else if ("convert".equals(localName)) {
sascha@415:                         convert(parent, (Element)current);
sascha@415:                     }
sascha@372:                     else {
sascha@372:                         log.warn("unknown '" + localName + "' -> ignore");
sascha@372:                     }
sascha@372:                 }
sascha@372:                 return;
sascha@372:             }
sascha@372: 
sascha@410:             if (current.getNodeType() == Node.TEXT_NODE) {
sascha@410:                 String txt = current.getNodeValue();
sascha@410:                 if (txt != null && txt.trim().length() == 0) {
sascha@410:                     return;
sascha@410:                 }
sascha@410:             }
sascha@410: 
sascha@963:             Node copy = owner.importNode(current, false);
sascha@372: 
sascha@372:             NodeList children = current.getChildNodes();
sascha@372:             for (int i = 0, N = children.getLength(); i < N; ++i) {
sascha@372:                 build(copy, children.item(i));
sascha@372:             }
sascha@372:             parent.appendChild(copy);
sascha@372:         }
sascha@372:     } // class BuildHelper
sascha@372: 
sascha@372: 
sascha@372:     public Builder() {
sascha@973:         compiledStatements = new HashMap<String, CompiledStatement>();
sascha@372:     }
sascha@372: 
sascha@372:     public Builder(Document template) {
sascha@973:         this();
sascha@372:         this.template = template;
sascha@973:         compileStatements();
sascha@973:     }
sascha@973: 
sascha@973:     protected void compileStatements() {
sascha@973: 
sascha@973:         NodeList nodes = template.getElementsByTagNameNS(
sascha@973:             DC_NAMESPACE_URI, "statement");
sascha@973: 
sascha@973:         for (int i = 0, N = nodes.getLength(); i < N; ++i) {
sascha@973:             Element stmntElement = (Element)nodes.item(i);
sascha@973:             String stmnt = trimStatement(stmntElement.getTextContent());
sascha@973:             if (stmnt == null || stmnt.length() == 0) {
sascha@973:                 throw new IllegalArgumentException("found empty statement");
sascha@973:             }
sascha@973:             CompiledStatement cs = new CompiledStatement(stmnt);
sascha@973:             // for faster lookup store a shortend string into the template
sascha@973:             stmnt = "s" + i;
sascha@973:             stmntElement.setTextContent(stmnt);
sascha@973:             compiledStatements.put(stmnt, cs);
sascha@973:         }
sascha@372:     }
sascha@372: 
sascha@963:     protected static List<Node> rootsToList(NodeList roots) {
sascha@372: 
sascha@372:         List<Node> elements = new ArrayList<Node>();
sascha@372: 
sascha@372:         for (int i = 0, N = roots.getLength(); i < N; ++i) {
sascha@372:             NodeList rootChildren = roots.item(i).getChildNodes();
sascha@372:             for (int j = 0, M = rootChildren.getLength(); j < M; ++j) {
sascha@372:                 Node child = rootChildren.item(j);
sascha@372:                 if (child.getNodeType() == Node.ELEMENT_NODE) {
sascha@372:                     elements.add(child);
sascha@372:                 }
sascha@372:             }
sascha@372:         }
sascha@372: 
sascha@963:         return elements;
sascha@963:     }
sascha@963: 
sascha@972:     protected static final String trimStatement(String stmnt) {
sascha@973:         if (stmnt == null) return null;
sascha@972:         //XXX: Maybe a bit to radical for multiline strings?
sascha@972:         return STRIP_LINE_INDENT.matcher(stmnt.trim()).replaceAll(" ");
sascha@972:     }
sascha@972: 
sascha@972:     protected static Document getOwnerDocument(Node node) {
sascha@972:         Document document = node.getOwnerDocument();
sascha@972:         return document != null ? document : (Document)node;
sascha@972:     }
sascha@972: 
sascha@963:     public void build(
sascha@963:         Connection          connection,
sascha@963:         Node                output,
sascha@963:         Map<String, Object> parameters
sascha@963:     )
sascha@963:     throws SQLException
sascha@963:     {
sascha@963:         BuildHelper helper = new BuildHelper(output, connection, parameters);
sascha@963: 
sascha@963:         NodeList roots = template.getElementsByTagNameNS(
sascha@963:             DC_NAMESPACE_URI, "template");
sascha@963: 
sascha@963:         helper.build(rootsToList(roots));
sascha@372:     }
sascha@372: }
sascha@372: // vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8 :