/* 
@ITMillApache2LicenseForJavaFiles@
 */

package com.itmill.toolkit.terminal;

import java.io.InputStream;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;

/**
 * Downloadable stream.
 * 
 * @author IT Mill Ltd.
 * @version
 * @VERSION@
 * @since 3.0
 */
public class DownloadStream {

    /**
     * Maximum cache time.
     */
    public static final long MAX_CACHETIME = Long.MAX_VALUE;

    /**
     * Default cache time.
     */
    public static final long DEFAULT_CACHETIME = 1000 * 60 * 60 * 24;

    private InputStream stream;

    private String contentType;

    private String fileName;

    private Map params;

    private long cacheTime = DEFAULT_CACHETIME;

    private int bufferSize = 0;

    /**
     * Creates a new instance of DownloadStream.
     */
    public DownloadStream(InputStream stream, String contentType,
            String fileName) {
        setStream(stream);
        setContentType(contentType);
        setFileName(fileName);
    }

    /**
     * Gets downloadable stream.
     * 
     * @return output stream.
     */
    public InputStream getStream() {
        return stream;
    }

    /**
     * Sets the stream.
     * 
     * @param stream
     *                The stream to set
     */
    public void setStream(InputStream stream) {
        this.stream = stream;
    }

    /**
     * Gets stream content type.
     * 
     * @return type of the stream content.
     */
    public String getContentType() {
        return contentType;
    }

    /**
     * Sets stream content type.
     * 
     * @param contentType
     *                the contentType to set
     */
    public void setContentType(String contentType) {
        this.contentType = contentType;
    }

    /**
     * Returns the file name.
     * 
     * @return the name of the file.
     */
    public String getFileName() {
        return fileName;
    }

    /**
     * Sets the file name.
     * 
     * @param fileName
     *                the file name to set.
     */
    public void setFileName(String fileName) {
        this.fileName = fileName;
    }

    /**
     * Sets a paramater for download stream. Parameters are optional information
     * about the downloadable stream and their meaning depends on the used
     * adapter. For example in WebAdapter they are interpreted as HTTP response
     * headers.
     * 
     * If the parameters by this name exists, the old value is replaced.
     * 
     * @param name
     *                the Name of the parameter to set.
     * @param value
     *                the Value of the parameter to set.
     */
    public void setParameter(String name, String value) {
        if (params == null) {
            params = new HashMap();
        }
        params.put(name, value);
    }

    /**
     * Gets a paramater for download stream. Parameters are optional information
     * about the downloadable stream and their meaning depends on the used
     * adapter. For example in WebAdapter they are interpreted as HTTP response
     * headers.
     * 
     * @param name
     *                the Name of the parameter to set.
     * @return Value of the parameter or null if the parameter does not exist.
     */
    public String getParameter(String name) {
        if (params != null) {
            return (String) params.get(name);
        }
        return null;
    }

    /**
     * Gets the names of the parameters.
     * 
     * @return Iterator of names or null if no parameters are set.
     */
    public Iterator getParameterNames() {
        if (params != null) {
            return params.keySet().iterator();
        }
        return null;
    }

    /**
     * Gets length of cache expiration time. This gives the adapter the
     * possibility cache streams sent to the client. The caching may be made in
     * adapter or at the client if the client supports caching. Default is
     * <code>DEFAULT_CACHETIME</code>.
     * 
     * @return Cache time in milliseconds
     */
    public long getCacheTime() {
        return cacheTime;
    }

    /**
     * Sets length of cache expiration time. This gives the adapter the
     * possibility cache streams sent to the client. The caching may be made in
     * adapter or at the client if the client supports caching. Zero or negavive
     * value disbales the caching of this stream.
     * 
     * @param cacheTime
     *                the cache time in milliseconds.
     */
    public void setCacheTime(long cacheTime) {
        this.cacheTime = cacheTime;
    }

    /**
     * Gets the size of the download buffer.
     * 
     * @return int The size of the buffer in bytes.
     */
    public int getBufferSize() {
        return bufferSize;
    }

    /**
     * Sets the size of the download buffer.
     * 
     * @param bufferSize
     *                the size of the buffer in bytes.
     */
    public void setBufferSize(int bufferSize) {
        this.bufferSize = bufferSize;
    }

}