/*******************************************************************************
 * Copyright (c) 2012 IT Just working.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     IT Just working - initial API and implementation
 *******************************************************************************/
package com.minres.scviewer.database.text;

import java.nio.charset.CharsetDecoder;
import java.util.Collection;
import java.util.zip.GZIPInputStream

import org.codehaus.groovy.ast.stmt.CatchStatement
import org.mapdb.DB
import org.mapdb.DBMaker

import groovy.io.FileType

import com.minres.scviewer.database.AssociationType
import com.minres.scviewer.database.DataType
import com.minres.scviewer.database.IWaveform
import com.minres.scviewer.database.IWaveformDb
import com.minres.scviewer.database.IWaveformDbLoader
import com.minres.scviewer.database.RelationType
import com.minres.scviewer.database.tx.ITxGenerator

public class TextDbLoader implements IWaveformDbLoader{

	private Long maxTime;

	IWaveformDb db;

	def streams = []

	def relationTypes=[:]

	DB mapDb
	
	public TextDbLoader() {
	}

	@Override
	public Long getMaxTime() {
		return maxTime;
	}

	@Override
	public Collection<IWaveform> getAllWaves() {
		return streams;
	}

	public Map<Long, ITxGenerator> getGeneratorsById() {
		TreeMap<Long, ITxGenerator> res = new TreeMap<Long, ITxGenerator>();
		streams.each{TxStream stream -> stream.generators.each{res.put(it.id, id)} }
		return res;
	}

	static final byte[] x = "scv_tr_stream".bytes

	@Override
	boolean load(IWaveformDb db, File file) throws Exception {
		if(file.isDirectory() || !file.exists()) return false;
		this.db=db
		this.streams=[]
		try {
			def gzipped = isGzipped(file)
			if(isTxfile(gzipped?new GZIPInputStream(new FileInputStream(file)):new FileInputStream(file))){
				def mapDbFile = File.createTempFile("."+file.name, null /*"tmp"*/, null /*file.parentFile*/)
				mapDbFile.delete()
				mapDbFile.deleteOnExit()
				this.mapDb = DBMaker
				.fileDB(mapDbFile)
				.fileMmapEnableIfSupported()
				.fileMmapPreclearDisable()
				.cleanerHackEnable()
				.allocateStartSize(64*1024*1024)
				.allocateIncrement(64*1024*1024)
				.make()
				// NPE here --->
				parseInput(gzipped?new GZIPInputStream(new FileInputStream(file)):new FileInputStream(file))
				streams.each{ TxStream  stream -> stream.getWidth() }
				return true
			}
		} catch (IndexOutOfBoundsException e) {
			return false
		} catch (IllegalArgumentException e) {
			return false
		} catch (NumberFormatException e) {
			return false
		} catch(EOFException e) {
			return true;
		} catch(Exception e) {
			System.out.println("---->>> Exception "+e.toString()+" caught while loading database");
			//System.out.println("---->>> Exception "+e.toString()+" caught while loading database. StackTrace following... ");
			//e.printStackTrace()
		} catch(Error e) {
			System.out.println("---->>> Exception "+e.toString()+" caught while loading database. StackTrace following... ");
			e.printStackTrace()
		}
		return false;
	}

	private static boolean isTxfile(InputStream istream) {
		byte[] buffer = new byte[x.size()]
		def readCnt = istream.read(buffer, 0, x.size())
		istream.close()
		if(readCnt==x.size()){
			for(int i=0; i<x.size(); i++)
				if(buffer[i]!=x[i]) return false
		}
		return true
	}

	private static boolean isGzipped(File f) {
		InputStream is = null;
		try {
			is = new FileInputStream(f);
			byte [] signature = new byte[2];
			int nread = is.read( signature ); //read the gzip signature
			return nread == 2 && signature[ 0 ] == (byte) 0x1f && signature[ 1 ] == (byte) 0x8b;
		} catch (IOException e) {
			return false;
		} finally {
			if(is!=null) is.close()
		}
	}

	private stringToScale(String scale){
		switch(scale.trim()){
			case "fs":return 1L
			case "ps":return 1000L
			case "ns":return 1000000L
			case "us":return 1000000000L
			case "ms":return 1000000000000L
			case "s": return 1000000000000000L
		}
		return 1L
	}
	
	private def parseInput(InputStream inputStream){
		def streamsById = [:]
		def generatorsById = [:]
		def transactionsById = [:]
		TxGenerator generator
		Tx transaction
		boolean endTransaction=false
		def matcher
		BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream, "UTF-8"));
		long lineCnt=0;
		reader.eachLine { line ->
			def tokens = line.split(/\s+/) as ArrayList
			switch(tokens[0]){
				case "scv_tr_stream":
					if ((matcher = line =~ /^scv_tr_stream\s+\(ID (\d+),\s+name\s+"([^"]+)",\s+kind\s+"([^"]+)"\)$/)) {
						def id = Integer.parseInt(matcher[0][1])
						def stream = new TxStream(this, id, matcher[0][2], matcher[0][3])
						streams<<stream
						streamsById[id]=stream
					}
					break;
				case "scv_tr_generator":
					if ((matcher = line =~ /^scv_tr_generator\s+\(ID\s+(\d+),\s+name\s+"([^"]+)",\s+scv_tr_stream\s+(\d+),$/)) {
						def id = Integer.parseInt(matcher[0][1])
						TxStream stream=streamsById[Integer.parseInt(matcher[0][3])] as TxStream
						generator=new TxGenerator(id, stream, matcher[0][2])
						stream.generators<<generator
						generatorsById[id]=generator
					}
					break;
				case "begin_attribute":
					if ((matcher = line =~ /^begin_attribute \(ID (\d+), name "([^"]+)", type "([^"]+)"\)$/)) {
						generator.begin_attrs << TxAttributeType.getAttrType(matcher[0][2], DataType.valueOf(matcher[0][3]), AssociationType.BEGIN)
					}
					break;
				case "end_attribute":
					if ((matcher = line =~ /^end_attribute \(ID (\d+), name "([^"]+)", type "([^"]+)"\)$/)) {
						generator.end_attrs << TxAttributeType.getAttrType(matcher[0][2], DataType.valueOf(matcher[0][3]), AssociationType.END)
					}
					break;
				case ")":
					generator=null
					break
				case "tx_begin"://matcher = line =~ /^tx_begin\s+(\d+)\s+(\d+)\s+(\d+)\s+([munpf]?s)/
					def id = Integer.parseInt(tokens[1])
					TxGenerator gen=generatorsById[Integer.parseInt(tokens[2])]
					transaction = new Tx(id, gen.stream, gen, Long.parseLong(tokens[3])*stringToScale(tokens[4]))
					gen.transactions << transaction
					transactionsById[id]= transaction
					gen.begin_attrs_idx=0;
					maxTime = maxTime>transaction.beginTime?maxTime:transaction.beginTime
					endTransaction=false
					break
				case "tx_end"://matcher = line =~ /^tx_end\s+(\d+)\s+(\d+)\s+(\d+)\s+([munpf]?s)/
					def id = Integer.parseInt(tokens[1])
					transaction = transactionsById[id]
					assert Integer.parseInt(tokens[2])==transaction.generator.id
					transaction.endTime = Long.parseLong(tokens[3])*stringToScale(tokens[4])
					transaction.generator.end_attrs_idx=0;
					maxTime = maxTime>transaction.endTime?maxTime:transaction.endTime
					endTransaction=true
					break
				case "tx_record_attribute"://matcher = line =~ /^tx_record_attribute\s+(\d+)\s+"([^"]+)"\s+(\S+)\s*=\s*(.+)$/
					def id = Integer.parseInt(tokens[1])
					def name = tokens[2][1..-2]
					def type = tokens[3] as DataType
					def remaining = tokens.size()>5?tokens[5..-1].join(' '):""
					transactionsById[id].attributes<<new TxAttribute(name, type, AssociationType.RECORD, remaining)
					break
				case "a"://matcher = line =~ /^a\s+(.+)$/
					if(endTransaction){
						transaction.attributes << new TxAttribute(transaction.generator.end_attrs[transaction.generator.end_attrs_idx], tokens[1])
						transaction.generator.end_attrs_idx++
					} else {
						transaction.attributes << new TxAttribute(transaction.generator.begin_attrs[transaction.generator.begin_attrs_idx], tokens[1])
						transaction.generator.begin_attrs_idx++
					}
					break
				case "tx_relation"://matcher = line =~ /^tx_relation\s+\"(\S+)\"\s+(\d+)\s+(\d+)$/
					Tx tr2= transactionsById[Integer.parseInt(tokens[2])]
					Tx tr1= transactionsById[Integer.parseInt(tokens[3])]
					def relType=tokens[1][1..-2]
					if(!relationTypes.containsKey(relType)) relationTypes[relType]=RelationType.create(relType)
					def rel = new TxRelation(relationTypes[relType], tr1, tr2)
					tr1.outgoingRelations<<rel
					tr2.incomingRelations<<rel
					break
				default:
					println "Don't know what to do with: '$line'"

			}
			lineCnt++
		}
	}

	public Collection<RelationType> getAllRelationTypes(){
		return relationTypes.values();
	}

}