/*
 * DigilibRequest.java
 *
 * lightweight class carrying all parameters for a request to digilib
 *

 Digital Image Library servlet components

 Copyright (C) 2001, 2002 Robert Casties (robcast@mail.berlios.de),
 Christian Luginbuehl

 This program is free software; you can redistribute  it and/or modify it
 under  the terms of  the GNU General  Public License as published by the
 Free Software Foundation;  either version 2 of the  License, or (at your
 option) any later version.
 
 Please read license.txt for the full details. A copy of the GPL
 may be found at http://www.gnu.org/copyleft/lgpl.html

 You should have received a copy of the GNU General Public License
 along with this program; if not, write to the Free Software
 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA

 * Created on 27. August 2002, 19:43
 */

package digilib.servlet;

import java.io.UnsupportedEncodingException;
import java.net.URLDecoder;
import java.util.Enumeration;
import java.util.StringTokenizer;

import javax.servlet.ServletRequest;
import javax.servlet.http.HttpServletRequest;

import digilib.image.DocuImage;
import digilib.io.FileOps;
import digilib.util.OptionsSet;
import digilib.util.Parameter;

/**
 * Class holding the parameters of a digilib user request. The parameters are
 * mostly named like the servlet parameters: <br>
 * request_path: url of the page/document. <br>
 * fn: url of the page/document. <br>
 * pn: page number. <br>
 * dw: width of result window in pixels. <br>
 * dh: height of result window in pixels. <br>
 * wx: left edge of image area (float from 0 to 1). <br>
 * wy: top edge of image area (float from 0 to 1). <br>
 * ww: width of image area(float from 0 to 1). <br>
 * wh: height of image area(float from 0 to 1). <br>
 * ws: scale factor. <br>
 * mo: special options like 'fit' for gifs. <br>
 * mk: list of marks. <br>
 * pt: total number of pages (generated by sevlet). <br>
 * baseURL: base URL (from http:// to below /servlet). <br>
 * ...et alii
 * 
 * @author casties
 * 
 */
public class DigilibServletRequest extends DigilibRequest {

    protected DocuImage image; // internal DocuImage instance for this request

    protected HttpServletRequest servletRequest; // internal ServletRequest

    /**
     * Creates a new instance of DigilibRequest with parameters from a
     * ServletRequest. All undefined parameters are set to default values.
     * 
     * @param request
     */
    public DigilibServletRequest(HttpServletRequest request) {
        setWithRequest(request);
        initOptions();
    }

    /**
     * set up parameters.
     * 
     */
    protected void initParams() {
        /*
         * Definition of parameters and default values. Parameter of type 's'
         * are for the servlet.
         */

        // url of the page/document (second part)
        newParameter("fn", "", null, 's');
        // page number
        newParameter("pn", new Integer(1), null, 's');
        // width of client in pixels
        newParameter("dw", new Integer(0), null, 's');
        // height of client in pixels
        newParameter("dh", new Integer(0), null, 's');
        // left edge of image (float from 0 to 1)
        newParameter("wx", new Float(0), null, 's');
        // top edge in image (float from 0 to 1)
        newParameter("wy", new Float(0), null, 's');
        // width of image (float from 0 to 1)
        newParameter("ww", new Float(1), null, 's');
        // height of image (float from 0 to 1)
        newParameter("wh", new Float(1), null, 's');
        // scale factor
        newParameter("ws", new Float(1), null, 's');
        // special options like 'fit' for gifs
        newParameter("mo", this.options, null, 's');
        // rotation angle (degree)
        newParameter("rot", new Float(0), null, 's');
        // contrast enhancement factor
        newParameter("cont", new Float(0), null, 's');
        // brightness enhancement factor
        newParameter("brgt", new Float(0), null, 's');
        // color multiplicative factors
        newParameter("rgbm", "0/0/0", null, 's');
        // color additive factors
        newParameter("rgba", "0/0/0", null, 's');
        // display dpi resolution (total)
        newParameter("ddpi", new Float(0), null, 's');
        // display dpi X resolution
        newParameter("ddpix", new Float(0), null, 's');
        // display dpi Y resolution
        newParameter("ddpiy", new Float(0), null, 's');
        // scale factor for mo=ascale
        newParameter("scale", new Float(1), null, 's');
        // color conversion operation
        newParameter("colop", "", null, 's');

        /*
         * Parameters of type 'i' are not exchanged between client and server,
         * but are for the servlets or JSPs internal use.
         */

        // url of the page/document (first part, may be empty)
        newParameter("request.path", "", null, 'i');
        // base URL (from http:// to below /servlet)
        newParameter("base.url", null, null, 'i');
        // DocuImage instance for this request
        newParameter("docu.image", image, null, 'i');
        image = null;
        // HttpServletRequest for this request
        newParameter("servlet.request", servletRequest, null, 'i');
        servletRequest = null;

        /*
         * Parameters of type 'c' are for the clients use
         */

        // "real" filename
        newParameter("img.fn", "", null, 'c');
        // image dpi x
        newParameter("img.dpix", new Integer(0), null, 'c');
        // image dpi y
        newParameter("img.dpiy", new Integer(0), null, 'c');
        // hires image size x
        newParameter("img.pix_x", new Integer(0), null, 'c');
        // hires image size y
        newParameter("img.pix_y", new Integer(0), null, 'c');
        // total number of pages
        newParameter("pt", new Integer(0), null, 'c');
        // marks
        newParameter("mk", "", null, 'c');
    }

    /*
     * (non-Javadoc)
     * 
     * @see digilib.servlet.ParameterMap#initOptions()
     */
    @Override
    protected void initOptions() {
        options = (OptionsSet) getValue("mo");
    }

    /**
     * Populate the request object with data from a ServletRequest.
     * 
     * 
     * @param request
     */
    public void setWithRequest(HttpServletRequest request) {
        servletRequest = request;
        // decide if it's old-style or new-style
        String qs = ((HttpServletRequest) request).getQueryString();
        if (qs != null) {
            if (qs.indexOf("&amp;") > -1) {
                // &amp; separator
                setWithParamString(qs, "&amp;");
            } else if (qs.indexOf(";") > -1) {
                // ; separator
                setWithParamString(qs, ";");
            } else if (request.getParameter("fn") != null || request.getParameter("dw") != null
                    || request.getParameter("dh") != null) {
                // standard '&' parameters
                setWithParamRequest(request);
            } else {
                setWithOldString(qs);
            }
        }
        setValue("servlet.request", request);
        // add path from request
        setValue("request.path", ((HttpServletRequest) request).getPathInfo());
        // set the baseURL
        setBaseURL((HttpServletRequest) request);
    }

    /**
     * Populate a request from a string in the old "++++" parameter form.
     * 
     * @param queryString
     *            String with paramters in the old "+++" form.
     */
    public void setWithOldString(String queryString) {
        if (queryString == null) {
            return;
        }
        // enable the passing of delimiter to get empty parameters
        StringTokenizer query = new StringTokenizer(queryString, "+", true);
        String token;
        // first parameter FN
        if (query.hasMoreTokens()) {
            token = query.nextToken();
            if (!token.equals("+")) {
                setValueFromString("fn", token);
                if (query.hasMoreTokens()) {
                    query.nextToken();
                }
            }
        }
        // second parameter PN
        if (query.hasMoreTokens()) {
            token = query.nextToken();
            if (!token.equals("+")) {
                setValueFromString("pn", token);
                if (query.hasMoreTokens()) {
                    query.nextToken();
                }
            }
        }
        // third parameter WS
        if (query.hasMoreTokens()) {
            token = query.nextToken();
            if (!token.equals("+")) {
                setValueFromString("ws", token);
                if (query.hasMoreTokens()) {
                    query.nextToken();
                }
            }
        }
        // fourth parameter MO
        if (query.hasMoreTokens()) {
            token = query.nextToken();
            if (!token.equals("+")) {
                setValueFromString("mo", token);
                if (query.hasMoreTokens()) {
                    query.nextToken();
                }
            }
        }
        // fifth parameter MK
        if (query.hasMoreTokens()) {
            token = query.nextToken();
            if (!token.equals("+")) {
                setValueFromString("mk", token);
                if (query.hasMoreTokens()) {
                    query.nextToken();
                }
            }
        }
        // sixth parameter WX
        if (query.hasMoreTokens()) {
            token = query.nextToken();
            if (!token.equals("+")) {
                setValueFromString("wx", token);
                if (query.hasMoreTokens()) {
                    query.nextToken();
                }
            }
        }
        // seventh parameter WY
        if (query.hasMoreTokens()) {
            token = query.nextToken();
            if (!token.equals("+")) {
                setValueFromString("wy", token);
                if (query.hasMoreTokens()) {
                    query.nextToken();
                }
            }
        }
        // eigth parameter WW
        if (query.hasMoreTokens()) {
            token = query.nextToken();
            if (!token.equals("+")) {
                setValueFromString("ww", token);
                if (query.hasMoreTokens()) {
                    query.nextToken();
                }
            }
        }
        // ninth parameter WH
        if (query.hasMoreTokens()) {
            token = query.nextToken();
            if (!token.equals("+")) {
                setValueFromString("wh", token);
                if (query.hasMoreTokens()) {
                    query.nextToken();
                }
            }
        }
    }

    /**
     * Return the request parameters as a String in the parameter form
     * 'fn=/icons&amp;pn=1'. Empty (undefined) fields are not included.
     * 
     * @return String of request parameters in parameter form.
     */
    public String getAsString() {
        return getAsString(0);
    }

    /**
     * Return the request parameters of a given type type as a String in the
     * parameter form 'fn=/icons&amp;pn=1'. Empty (undefined) fields are not
     * included.
     * 
     * @return String of request parameters in parameter form.
     */
    public String getAsString(int type) {
        StringBuffer s = new StringBuffer(50);
        // go through all values
        for (Parameter p : params.values()) {
            if ((type > 0) && (p.getType() != type)) {
                // skip the wrong types
                continue;
            }
            String name = p.getName();
            /*
             * handling special cases
             */
            // request_path adds to fn
            if (name.equals("fn")) {
                s.append("&fn=" + getAsString("request.path") + getAsString("fn"));
                continue;
            }
            /*
             * the rest is sent with its name
             */
            // parameters that are not set or internal are not sent
            if ((!p.hasValue()) || (p.getType() == 'i')) {
                continue;
            }
            s.append("&" + name + "=" + p.getAsString());
        }
        // kill first "&"
        s.deleteCharAt(0);
        return s.toString();
    }

    /**
     * Returns request parameters in old '++++' form.
     * 
     * @return String with parameters in old '++++' form.
     */
    public String getAsOldString() {
        StringBuffer s = new StringBuffer(50);
        s.append(getAsString("request.path"));
        s.append(getAsString("fn"));
        s.append("+" + getAsString("pn"));
        s.append("+" + getAsString("ws"));
        s.append("+" + getAsString("mo"));
        s.append("+" + getAsString("mk"));
        s.append("+" + getAsString("wx"));
        s.append("+" + getAsString("wy"));
        s.append("+" + getAsString("ww"));
        s.append("+" + getAsString("wh"));
        return s.toString();
    }

    /**
     * Set request parameters from javax.servlet.ServletRequest. Uses the
     * Requests getParameter methods for 'fn=foo' style parameters.
     * 
     * @param request
     *            ServletRequest to get parameters from.
     */
    // @SuppressWarnings("unchecked") // ServletRequest.getParameterNames()
    // returns naked Enumeration
    public void setWithParamRequest(ServletRequest request) {
        setValue("servlet.request", request);
        // go through all request parameters
        for (Enumeration<String> i = request.getParameterNames(); i.hasMoreElements();) {
            String name = (String) i.nextElement();
            // is this a known parameter?
            if (params.containsKey(name)) {
                Parameter p = (Parameter) this.get(name);
                // internal parameters are not set
                if (p.getType() == 'i') {
                    continue;
                }
                p.setValueFromString(request.getParameter(name));
                continue;
            }
            // unknown parameters are just added with type 'r'
            newParameter(name, null, request.getParameter(name), 'r');
        }
        // add path from request
        setValue("request.path", ((HttpServletRequest) request).getPathInfo());
    }

    /**
     * Set request parameters from query string. Uses the separator string qs to
     * get 'fn=foo' style parameters.
     * 
     * @param qs
     *            query string
     * @param sep
     *            parameter-separator string
     */
    public void setWithParamString(String qs, String sep) {
        // go through all request parameters
        String[] qa = qs.split(sep);
        for (int i = 0; i < qa.length; i++) {
            // split names and values on "="
            String[] nv = qa[i].split("=");
            try {
                String name = URLDecoder.decode(nv[0], "UTF-8");
                String val = URLDecoder.decode(nv[1], "UTF-8");
                // is this a known parameter?
                if (params.containsKey(name)) {
                    Parameter p = (Parameter) this.get(name);
                    // internal parameters are not set
                    if (p.getType() == 'i') {
                        continue;
                    }
                    p.setValueFromString(val);
                    continue;
                }
                // unknown parameters are just added with type 'r'
                newParameter(name, null, val, 'r');
            } catch (UnsupportedEncodingException e) {
                // this shouldn't happen anyway
                e.printStackTrace();
            }
        }
    }

    /**
     * Test if option string <code>opt</code> is set. Checks if the substring
     * <code>opt</code> is contained in the options string <code>param</code>.
     * Deprecated! use hasOption(String opt) for "mo"-options.
     * 
     * @param opt
     *            Option string to be tested.
     * @return boolean
     */
    public boolean hasOption(String param, String opt) {
        String s = getAsString(param);
        if (s != null) {
            StringTokenizer i = new StringTokenizer(s, ",");
            while (i.hasMoreTokens()) {
                if (i.nextToken().equals(opt)) {
                    return true;
                }
            }
        }
        return false;
    }

    /**
     * The image file path to be accessed.
     * 
     * The mage file path is assembled from the servlets RequestPath and
     * Parameter fn and normalized.
     * 
     * @return String the effective filepath.
     */
    public String getFilePath() {
        String s = getAsString("request.path");
        s += getAsString("fn");
        return FileOps.normalName(s);
    }

    /* Property getter and setter */

    /**
     * Set the requests base URL parameter from a
     * javax.sevlet.http.HttpServletRequest.
     * 
     * @param request
     *            HttpServletRequest to set the base URL.
     */
    public void setBaseURL(javax.servlet.http.HttpServletRequest request) {
        String baseURL = null;
        // calculate base URL string from request (minus last part)
        String s = request.getRequestURL().toString();
        int eop = s.lastIndexOf("/");
        if (eop > 0) {
            baseURL = s.substring(0, eop);
        } else {
            // fall back
            baseURL = "http://" + request.getServerName() + "/docuserver/digitallibrary";
        }
        setValue("base.url", baseURL);
    }

    /**
     * Returns the image.
     * 
     * @return DocuImage
     */
    public DocuImage getImage() {
        return image;
    }

    /**
     * Sets the image.
     * 
     * @param image
     *            The image to set
     */
    public void setImage(DocuImage image) {
        this.image = image;
        setValue("docu.image", image);
    }

    /**
     * @return
     */
    public HttpServletRequest getServletRequest() {
        return servletRequest;
    }

}