/*
  *  Copyright (C) 2022 github.com/REAndroid
  *
  *  Licensed under the Apache License, Version 2.0 (the "License");
  *  you may not use this file except in compliance with the License.
  *  You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
package com.reandroid.archive;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.zip.CRC32;
import java.util.zip.ZipEntry;

public abstract class InputSource {
    private final String name;
    private String alias;
    private long mCrc;
    private long mLength;
    private int method = ZipEntry.DEFLATED;
    private int sort;
    public InputSource(String name){
        this.name = name;
        this.alias = InputSourceUtil.sanitize(name);
    }
    public int getSort() {
        return sort;
    }
    public void setSort(int sort) {
        this.sort = sort;
    }
    public int getMethod() {
        return method;
    }
    public void setMethod(int method) {
        this.method = method;
    }

    public String getAlias(){
        if(alias!=null){
            return alias;
        }
        return getName();
    }
    public void setAlias(String alias) {
        this.alias = alias;
    }
    public void close(InputStream inputStream) throws IOException {
        inputStream.close();
    }
    public long write(OutputStream outputStream) throws IOException {
        return write(outputStream, openStream());
    }
    private long write(OutputStream outputStream, InputStream inputStream) throws IOException {
        long result=0;
        byte[] buffer=new byte[10240];
        int len;
        while ((len=inputStream.read(buffer))>0){
            outputStream.write(buffer, 0, len);
            result+=len;
        }
        close(inputStream);
        return result;
    }
    public String getName(){
        return name;
    }
    public long getLength() throws IOException{
        if(mLength==0){
            calculateCrc();
        }
        return mLength;
    }
    public long getCrc() throws IOException{
        if(mCrc==0){
            calculateCrc();
        }
        return mCrc;
    }
    public abstract InputStream openStream() throws IOException;
    @Override
    public boolean equals(Object o) {
        if (this == o) {
            return true;
        }
        if (!(o instanceof InputSource)) {
            return false;
        }
        InputSource that = (InputSource) o;
        return getName().equals(that.getName());
    }
    @Override
    public int hashCode() {
        return getName().hashCode();
    }
    @Override
    public String toString(){
        return getClass().getSimpleName()+": "+getName();
    }
    private void calculateCrc() throws IOException {
        InputStream inputStream=openStream();
        long length=0;
        CRC32 crc = new CRC32();
        int bytesRead;
        byte[] buffer = new byte[1024*64];
        while((bytesRead = inputStream.read(buffer)) != -1) {
            crc.update(buffer, 0, bytesRead);
            length+=bytesRead;
        }
        close(inputStream);
        mCrc=crc.getValue();
        mLength=length;
    }
}