FormInstanceXmlParser.java

package org.commcare.xml;

import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;
import java.util.Hashtable;

import javax.crypto.Cipher;
import javax.crypto.CipherOutputStream;
import javax.crypto.NoSuchPaddingException;
import javax.crypto.SecretKey;

import org.commcare.android.database.SqlStorage;
import org.commcare.android.database.user.models.FormRecord;
import org.commcare.android.logic.GlobalConstants;
import org.commcare.android.util.FileUtil;
import org.commcare.android.util.SessionUnavailableException;
import org.commcare.dalvik.application.CommCareApplication;
import org.commcare.dalvik.odk.provider.InstanceProviderAPI;
import org.commcare.dalvik.odk.provider.InstanceProviderAPI.InstanceColumns;
import org.commcare.data.xml.TransactionParser;
import org.commcare.xml.util.InvalidStructureException;
import org.javarosa.core.services.storage.IStorageUtilityIndexed;
import org.javarosa.core.services.storage.StorageFullException;
import org.kxml2.io.KXmlParser;
import org.kxml2.io.KXmlSerializer;
import org.kxml2.kdom.Document;
import org.kxml2.kdom.Element;
import org.kxml2.kdom.Node;
import org.xmlpull.v1.XmlPullParserException;

import android.content.ContentValues;
import android.content.Context;
import android.net.Uri;

/**
 * @author ctsims
 *
 */
public class FormInstanceXmlParser extends TransactionParser<FormRecord> {

    Context c;
    IStorageUtilityIndexed<FormRecord> storage;
    Hashtable<String, String> namespaces;
    int counter = 0;
    Cipher encrypter;
    
    private String destination;
    
    public FormInstanceXmlParser(KXmlParser parser, Context c, Hashtable<String, String> namespaces, String destination) {
        super(parser, null, null);
        this.c = c;
        this.namespaces = namespaces;
        this.destination = destination;
    }
    
    /*
     * (non-Javadoc)
     * @see org.commcare.data.xml.TransactionParser#parses(java.lang.String, java.lang.String)
     */
    @Override
    public boolean parses(String name, String namespace) {
        if(namespaces.containsKey(namespace)) {
            return true;
        }
        return false;
    }


    public FormRecord parse() throws InvalidStructureException, IOException, XmlPullParserException, SessionUnavailableException {
        String xmlns = parser.getNamespace();
        //Parse this subdocument into a dom
        Element element = new Element();
        element.setName(parser.getName());
        element.setNamespace(parser.getNamespace());
        element.parse(this.parser);
        
        //Consume the end tag.
        //this.parser.next();
        
        //create an actual document out of it.
        Document document = new Document();
        document.addChild(Node.ELEMENT, element);    
        
        KXmlSerializer serializer = new KXmlSerializer();
    
        SecretKey key = CommCareApplication._().createNewSymetricKey();
        
        
        String filePath = getFileDestination(namespaces.get(xmlns), destination);
        
        //Register this instance for inspection
        ContentValues values = new ContentValues();
        values.put(InstanceColumns.DISPLAY_NAME, "Historical Form");
        values.put(InstanceColumns.SUBMISSION_URI, "");
        values.put(InstanceColumns.INSTANCE_FILE_PATH, filePath);
        values.put(InstanceColumns.JR_FORM_ID, xmlns);
        values.put(InstanceColumns.STATUS, InstanceProviderAPI.STATUS_COMPLETE);
        values.put(InstanceColumns.CAN_EDIT_WHEN_COMPLETE, false);
        
        Uri instanceRecord = c.getContentResolver().insert(InstanceColumns.CONTENT_URI,values);

        
        FormRecord r = new FormRecord(instanceRecord.toString(), FormRecord.STATUS_UNINDEXED, xmlns, key.getEncoded(),null, new Date(0));
        IStorageUtilityIndexed<FormRecord> storage =  storage();
        
        OutputStream o = new FileOutputStream(filePath);
        CipherOutputStream cos = null;
        BufferedOutputStream bos = null;
        
        try {
            if(encrypter == null) {
                encrypter = Cipher.getInstance(key.getAlgorithm());
            }

            encrypter.init(Cipher.ENCRYPT_MODE, key);
            cos = new CipherOutputStream(o, encrypter);
            bos = new BufferedOutputStream(cos,1024*256);
            
        
            serializer.setOutput(bos, "UTF-8");
        
            document.write(serializer);
        
            storage.write(r);
            
        } catch (StorageFullException e) {
            throw new IOException(e.getMessage());
        } 
        //There's nothing we can do about any of these in code, failfast.
        catch (NoSuchAlgorithmException e) {
            throw new RuntimeException(e.getMessage());
        } catch (NoSuchPaddingException e) {
            throw new RuntimeException(e.getMessage());
        } catch (InvalidKeyException e) {
            throw new RuntimeException(e.getMessage());
        } finally {
            //since bos might not have even been created.
            if(bos != null) {
                bos.close();
            } else {
                o.close();
            }
        }
        return r;
    }
    
    public IStorageUtilityIndexed<FormRecord> storage() throws SessionUnavailableException{
        if(storage == null) {
            storage =  CommCareApplication._().getUserStorage(FormRecord.class);
        } 
        return storage;
    }
    
    private String getFileDestination(String formPath, String instancePath) {
        // Create new answer folder.
        String time = new SimpleDateFormat("yyyy-MM-dd_HH-mm-ss").format(Calendar.getInstance().getTime()) + counter;
        String file = formPath.substring(formPath.lastIndexOf('/') + 1, formPath.lastIndexOf('.'));
        counter++;
        
        String path = instancePath + file + "_" + time;
        if (FileUtil.createFolder(path)) {
            return new File(path + "/" + file + "_" + time + ".xml").getAbsolutePath();
        }
        throw new RuntimeException("Couldn't create folder needed to save form instance");
    }

    /*
     * (non-Javadoc)
     * @see org.commcare.data.xml.TransactionParser#commit(java.lang.Object)
     */
    @Override
    public void commit(FormRecord parsed) throws IOException {
        //This is unused.
    }
}