package com.android.download;



import com.android.database.lib.DownLoadTaskBean;
import com.android.util.LogUtils;

import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.io.RandomAccessFile;
import java.net.HttpURLConnection;
import java.net.URL;

public class DownLoadTaskThread implements Runnable {
    private boolean pause;
    private DownLoadTaskBean bean;
    private long currentTotal = 0;
    private DownloadTaskObserver observer;

    public DownLoadTaskThread(DownLoadTaskBean bean, DownloadTaskObserver observer) {
        this.bean = bean;
        this.observer = observer;
    }

    @Override
    public void run() {
        HttpURLConnection urlConnection=null;
        RandomAccessFile randomFile=null;
        InputStream inputStream =null;
        try {
            URL url = new URL(bean.getUrl());
            urlConnection = (HttpURLConnection) url.openConnection();
            urlConnection.setConnectTimeout(20000);      //设置连接超时事件为20秒
            urlConnection.setRequestMethod("GET");      //设置请求方式为GET
            //设置用户端可以接收的媒体类型
            urlConnection.setRequestProperty("Accept", "image/gif, image/jpeg, image/pjpeg, " +
                    "image/pjpeg, application/x-shockwave-flash, application/xaml+xml, " +
                    "application/vnd.ms-xpsdocument, application/x-ms-xbap," +
                    " application/x-ms-application, application/vnd.ms-excel," +
                    " application/vnd.ms-powerpoint, application/msword, */*");

            urlConnection.setRequestProperty("Accept-Language", "zh-CN");  //设置用户语言
            urlConnection.setRequestProperty("Charset", "UTF-8");    //设置客户端编码
            //设置用户代理
            urlConnection.setRequestProperty("User-Agent", "Mozilla/4.0 (compatible; MSIE 8.0; " +
                    "Windows NT 5.2; Trident/4.0; .NET CLR 1.1.4322; .NET CLR 2.0.50727;" +
                    " .NET CLR 3.0.04506.30; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729)");

            File dataFile = new File(bean.getPath(), bean.getFileName());
            if(dataFile.exists()&&dataFile.length()==bean.getTotal()){  //判断该文件已下载无需再下载
                LogUtils.loge("dont need download "+bean.getFileName());
                observer.onFinish(bean, bean.getTaskId(), dataFile.length());
                return;
            }

            //设置文件写入位置
            File file = new File(bean.getPath(), bean.getFileName()+"-tmp");
            if(!file.exists()){
                file.createNewFile();
            }
            currentTotal = file.length();
            LogUtils.loge(bean.getStart() + "start------" + currentTotal  + ">>>>" + bean.getTotal());
            if(currentTotal==bean.getTotal()){
                File targFile = new File(bean.getPath(), bean.getFileName());
                file.renameTo(targFile);//重命名
                Thread.sleep(3000);
                observer.onFinish(bean, bean.getTaskId(), currentTotal);
                file.delete();//删除临时文件
                return;
            }
            //设置下载位置
            urlConnection.setRequestProperty("Range", "bytes=" + currentTotal + "-");

            randomFile = new RandomAccessFile(file, "rwd");
            randomFile.seek(currentTotal);
            urlConnection.connect();
            if (observer != null) {
                observer.onStart(bean, bean.getTaskId());
            }

            //获得文件流
            inputStream = urlConnection.getInputStream();
            byte[] buffer = new byte[1024*10];
            int len;
            long time = System.currentTimeMillis();
            while ( (currentTotal!=bean.getTotal())&&(len = inputStream.read(buffer)) != -1) {

                //写入文件
                randomFile.write(buffer, 0, len);
                currentTotal += len;
                //时间间隔大于500ms再发
                if (System.currentTimeMillis() - time > 500) {
                    time = System.currentTimeMillis();
                    observer.onProgress(bean, bean.getTaskId(), currentTotal);
                }
                //判断是否是暂停状态.保存断点
                if (observer != null && pause) {
                    break;
                }
            }

            urlConnection.disconnect();
            urlConnection=null;
            randomFile.close();
            randomFile=null;
            inputStream.close();
            inputStream=null;

            observer.onProgress(bean, bean.getTaskId(), currentTotal);

            if (observer != null && !pause) {
                if(currentTotal == bean.getTotal()) {
                    LogUtils.loge("下载完成");
                    LogUtils.loge("download Exception===>sleeping before");
                    File targFile = new File(bean.getPath(), bean.getFileName());
                    file.renameTo(targFile);//重命名
                    Thread.sleep(3000);
                    LogUtils.loge("download Exception===>sleeping after");
                    observer.onFinish(bean, bean.getTaskId(), currentTotal);
                    file.delete();//删除临时文件
                }else {
                    LogUtils.loge("下载失败");
                    if (observer != null) {
                        observer.onError(bean, bean.getTaskId(), "下载失败");
                    }
                }
            }
        } catch (Exception e) {
            e.printStackTrace();
            LogUtils.loge("download Exception===>"+e.getMessage());
            if (observer != null) {
                observer.onError(bean, bean.getTaskId(), e.getMessage());
            }
        }finally {
            if(urlConnection!=null) {
                urlConnection.disconnect();
                urlConnection=null;
            }
            try {
                if(randomFile!=null) {
                    randomFile.close();
                    randomFile=null;
                }

            } catch (IOException e) {
                e.printStackTrace();
            }

            try {
                if(inputStream!=null) {
                    inputStream.close();
                    inputStream=null;
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }

    public DownLoadTaskBean getBean() {
        return bean;
    }

    public void setBean(DownLoadTaskBean bean) {
        this.bean = bean;
    }

    public void setPause(boolean pause) {
        this.pause = pause;
    }




    protected static abstract class DownloadTaskObserver {

        protected abstract void onStart(DownLoadTaskBean bean, long taskId);

        protected abstract void onProgress(DownLoadTaskBean bean, long taskId, long progress);

        protected abstract void onFinish(DownLoadTaskBean bean, long taskId, long lastProgress);

        protected abstract void onPause(DownLoadTaskBean bean, long taskId, long currentProgress);

        protected abstract void onError(DownLoadTaskBean bean, long taskId, String erroMsg);
    }
}