package application.parsing;

import java.text.ParseException;
import java.util.Calendar;
import java.util.GregorianCalendar;
import java.util.HashMap;

import org.xml.sax.Attributes;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.DefaultHandler;

import application.enums.BiologicalSex;
import application.enums.BloodType;
import application.enums.EntryType;
import application.enums.SkinType;
import application.helpers.Utils;
import application.res.Text;

/**
 * This class is in charge of reading in the data of the file and getting an overview of the data.
 * @author Bianca
 *
 */
public class ReadHandler extends DefaultHandler
{
	/** The date the health data was exported**/
	private String exportDate;
	/** the biological sex given in the health data **/
	private BiologicalSex bSex;
	/** the blood type given in the health data **/
	private BloodType bloodType;
	/** the skin type given in the health data **/
	private SkinType skinType;
	/** the region code given in the health data **/
	private String regionCode;
	/** the date of birth as a string given in the health data**/
	private String dateOfBirthString;
	/** the date of birth saved in a calendar**/
	private Calendar dateOfBirth;
	/** contains as a key the name of tags (e.g EntryTypes) and as value the number of occurrences**/
	private HashMap<String, Integer> names=new HashMap<>();
	/** contains as a key the name of the sub workout and as value the number of occurrences **/
	private HashMap<String, Integer> subWorkouts=new HashMap<>();
	/** contains as a key the name of the sub records and as value the number of occurrences **/
	private HashMap<String, Integer> subRecords=new HashMap<>();
	/** keeps track of the tag layer. With every new element we increase the layer by one**/
	private int overallLayer=0;
	
	@Override
	public void startElement(String uri, String localName, String qName, Attributes attributes) throws SAXException 
	{
		//increase layer
		if(overallLayer>0)
		{
			overallLayer++;
		}
		
		if (qName.equalsIgnoreCase(Text.TAG_NAME_HEALTH_DATA)) 
		{	//outermost tag (overallLayer==0)
			overallLayer++;
			regionCode=attributes.getValue(Text.TAG_ATTR_REGION_CODE);
		} 
		else if (qName.equalsIgnoreCase(EntryType.EXPORT_DATE.getValue())) 
		{
			exportDate=attributes.getValue(Text.TAG_ATTR_EXPORT_DATE);
		} 
		else if (qName.equalsIgnoreCase(Text.TAG_NAME_ME_INFO)) 
		{
			bSex = BiologicalSex.getValue(attributes.getValue(Text.TAG_ATTR_BIOLOGICAL_SEX));
			dateOfBirthString = attributes.getValue(Text.TAG_ATTR_DATE_OF_BIRTH);
			bloodType = BloodType.getValue(attributes.getValue(Text.TAG_ATTR_BLOOD_TYPE));
			skinType = SkinType.getValue(attributes.getValue(Text.TAG_ATTR_SKIN_TYPE));
			if(dateOfBirthString!=null&&!dateOfBirthString.equals(""))
			{
				try
				{
					dateOfBirth=new GregorianCalendar();
					dateOfBirth.setTime(Utils.formatDateOfBirth.parse(dateOfBirthString));
				} catch (ParseException e)
				{
					dateOfBirth=null;
					//do nth if parsing error
				}
			}
		} 
		else if (qName.equalsIgnoreCase(EntryType.RECORD.getValue())) 
		{
			String subRecord=attributes.getValue(Text.TAG_ATTR_RECORD_TYPE);
			Integer j = subRecords.get(subRecord);
			if (j == null)
			{
				j = 0;
			}
			subRecords.put(subRecord, ++j);
		} 
		else if (qName.equalsIgnoreCase(EntryType.WORKOUT.getValue())) 
		{
			String subWorkout=attributes.getValue(Text.TAG_ATTR_WORKOUT_TYPE);
			Integer j = subWorkouts.get(subWorkout);
			if (j == null)
			{
				j = 0;
			}
			subWorkouts.put(subWorkout, ++j);
		}
				
		if(overallLayer==2) //layer 2 means direct descendants of the document root (HealthData-tag)
		{
			Integer v=names.get(qName);
			if (v==null)
			{
				v=0;
			}
			
			names.put(qName, ++v);
		}
	}

	@Override
	public void endElement(String uri, String localName, String qName) throws SAXException 
	{
		//decrease layer
		if(overallLayer>0)
		{
			overallLayer--;
		}
	}
	
	/**
	 * Returns the selected value from ME or ExportDate.
	 * 
	 * @param type Value to find the info for.
	 * @return Found value if it was a valid entry of ME or the export Date,
	 *         {@code null} otherwise
	 */
	public String getMeInfo(EntryType type)
	{
		if (type.equals(EntryType.BIOLOGICAL_SEX))
		{
			return bSex.getReadableValue();
		} else if (type.equals(EntryType.DATE_OF_BIRTH))
		{
			return getDateOfBirth();
		}
		if (type.equals(EntryType.BLOOD_TYPE))
		{
			return bloodType.getReadableValue();
		}
		if (type.equals(EntryType.SKIN_TYPE))
		{
			return skinType.getReadableValue();
		}
		return null;
	}

	/**
	 * Returns the day the health data was exported
	 * @return the described value.
	 */
	public String getExportDate()
	{
		return exportDate;
	}

	/**
	 * Returns the region code given in the file.
	 * @return the described value.
	 */
	public String getRegionCode()
	{
		return regionCode;
	}

	/**
	 * Finds out how many Entries of the given EntryTypes can be found in the
	 * document
	 * 
	 * @param type EntryType to find the count to
	 * @return 0 if there are none, otherwise the correct number of entries
	 */
	public int getTypeNumber(EntryType type)
	{
		if (names.get(type.getValue()) == null)
		{
			return 0;
		}
		return names.get(type.getValue());
	}
	
	/**
	 * Returns the year of birth if the data was given in the file. Otherwise returns -1.
	 * @return the described value.
	 */
	public int getDateOfBirthYear()
	{
		if(dateOfBirth!=null)
		{
			return dateOfBirth.get(Calendar.YEAR);
		}
		return -1;
	}
	
	/**
	 * Returns the month of birth if the data was given in the file. Otherwise returns -1.
	 * @return the described value.
	 */
	public int getDateOfBirthMonth()
	{
		if(dateOfBirth!=null)
		{
			return dateOfBirth.get(Calendar.MONTH)+1;
		}
		return -1;
	}
	
	/**
	 * Returns the day of birth if the data was given in the file. Otherwise returns -1.
	 * @return the described value.
	 */
	public int getDateOfBirthDay()
	{
		if(dateOfBirth!=null)
		{
			return dateOfBirth.get(Calendar.DAY_OF_MONTH);
		}
		return -1;
	}

	/**
	 * Returns the SubWorkouts with their respective occurrences
	 * @return The described value
	 */
	public HashMap<String, Integer> getSubWorkouts()
	{
		return subWorkouts;
	}

	/**
	 * Returns the SubRecords with their respective occurrences
	 * @return The described value
	 */
	public HashMap<String, Integer> getSubRecords()
	{
		return subRecords;
	}

	/**
	 * Returns the date of birth as the String read in the file
	 * @return The described value.
	 */
	public String getDateOfBirth()
	{
		return dateOfBirthString;
	}
	
	/**
	 * Returns the date of birth split into 3 parts (day, month, year)
	 * @return the described value
	 */
	public HashMap<String, Integer> getSplitDateOfBirth()
	{
		HashMap<String, Integer> res= new HashMap<>();
		if(getDateOfBirthDay()>0)
		{
			res.put(Text.DAY, getDateOfBirthDay());
		}
		if(getDateOfBirthMonth()>0)
		{
			res.put(Text.MONTH, getDateOfBirthMonth());
		}
		if(getDateOfBirthYear()>0)
		{
			res.put(Text.YEAR, getDateOfBirthYear());
		}
		return res;
	}

	/**
	 * Returns the biological sex as given in the file
	 * @return the described value
	 */
	public BiologicalSex getBSex()
	{
		return bSex;
	}
}