/*******************************************************************************
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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 org.apache.ofbiz.common;

import java.awt.Color;
import java.awt.Font;
import java.awt.FontMetrics;
import java.awt.Graphics2D;
import java.awt.geom.AffineTransform;
import java.awt.image.BufferedImage;
import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.LineNumberReader;
import java.io.UnsupportedEncodingException;
import java.io.Writer;
import java.net.URL;
import java.util.HashMap;
import java.util.Map;

import javax.imageio.ImageIO;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import org.apache.commons.lang.RandomStringUtils;
import org.apache.commons.lang.StringUtils;
import org.apache.ofbiz.base.lang.JSON;
import org.apache.ofbiz.base.location.FlexibleLocation;
import org.apache.ofbiz.base.util.Debug;
import org.apache.ofbiz.base.util.UtilGenerics;
import org.apache.ofbiz.base.util.UtilHttp;
import org.apache.ofbiz.base.util.UtilProperties;
import org.apache.ofbiz.base.util.UtilValidate;
import org.apache.ofbiz.base.util.string.FlexibleStringExpander;
import org.apache.ofbiz.entity.Delegator;
import org.apache.ofbiz.entity.GenericEntityException;
import org.apache.ofbiz.entity.GenericValue;
import org.apache.ofbiz.entity.util.EntityUtilProperties;
import org.apache.ofbiz.webapp.control.JWTManager;
import org.apache.ofbiz.webapp.control.LoginWorker;
import org.apache.ofbiz.widget.model.ModelWidget;
import org.apache.ofbiz.widget.model.ScriptLinkHelper;
import org.apache.ofbiz.widget.model.ThemeFactory;
import org.apache.ofbiz.widget.renderer.VisualTheme;

/**
 * Common Services
 */
public class CommonEvents {

    private static final String MODULE = CommonEvents.class.getName();

    // Attributes removed for security reason; _ERROR_MESSAGE_ and _ERROR_MESSAGE_LIST are kept
    private static final String[] IGNOREATTRS = new String[] {
        "javax.servlet.request.key_size",
        "_CONTEXT_ROOT_",
        "_FORWARDED_FROM_SERVLET_",
        "javax.servlet.request.ssl_session",
        "javax.servlet.request.ssl_session_id",
        "multiPartMap",
        "javax.servlet.request.cipher_suite",
        "targetRequestUri",
        "_SERVER_ROOT_URL_",
        "_CONTROL_PATH_",
        "thisRequestUri",
        "org.apache.tomcat.util.net.secure_protocol_version",
        "userLogin",
        "impersonateLogin",
        "requestMapMap" // requestMapMap is used by CSRFUtil
    };

    /**
     * Simple event to set the users per-session locale setting. The user's locale setting should be passed as a
     * "newLocale" request parameter.
     */
    public static String setSessionLocale(HttpServletRequest request, HttpServletResponse response) {
        String localeString = request.getParameter("newLocale");
        if (UtilValidate.isNotEmpty(localeString)) {
            UtilHttp.setLocale(request, localeString);

            // update the UserLogin object
            GenericValue userLogin = (GenericValue) request.getSession().getAttribute("userLogin");
            if (userLogin == null) {
                userLogin = (GenericValue) request.getSession().getAttribute("autoUserLogin");
            }

            if (userLogin != null) {
                GenericValue ulUpdate = GenericValue.create(userLogin);
                ulUpdate.set("lastLocale", localeString);
                try {
                    ulUpdate.store();
                    userLogin.refreshFromCache();
                } catch (GenericEntityException e) {
                    Debug.logWarning(e, MODULE);
                }
            }
        }
        return "success";
    }

    /** Simple event to set the user's per-session time zone setting. */
    public static String setSessionTimeZone(HttpServletRequest request, HttpServletResponse response) {
        String tzString = request.getParameter("tzId");
        if (UtilValidate.isNotEmpty(tzString)) {
            UtilHttp.setTimeZone(request, tzString);

            // update the UserLogin object
            GenericValue userLogin = (GenericValue) request.getSession().getAttribute("userLogin");
            if (userLogin == null) {
                userLogin = (GenericValue) request.getSession().getAttribute("autoUserLogin");
            }

            if (userLogin != null) {
                GenericValue ulUpdate = GenericValue.create(userLogin);
                ulUpdate.set("lastTimeZone", tzString);
                try {
                    ulUpdate.store();
                    userLogin.refreshFromCache();
                } catch (GenericEntityException e) {
                    Debug.logWarning(e, MODULE);
                }
            }
        }
        return "success";
    }

    /** Simple event to set the user's per-session theme setting. */
    public static String setSessionTheme(HttpServletRequest request, HttpServletResponse response) {
        String visualThemeId = request.getParameter("userPrefValue");
        if (UtilValidate.isNotEmpty(visualThemeId)) {
            VisualTheme visualTheme = ThemeFactory.getVisualThemeFromId(visualThemeId);
            if (visualTheme != null) {
                UtilHttp.setVisualTheme(request, visualTheme);
            }
        }
        return "success";
    }

    /** Simple event to set the users per-session currency uom value */
    public static String setSessionCurrencyUom(HttpServletRequest request, HttpServletResponse response) {
        String currencyUom = request.getParameter("currencyUom");
        if (UtilValidate.isNotEmpty(currencyUom)) {
            // update the session
            UtilHttp.setCurrencyUom(request.getSession(), currencyUom);

            // update the UserLogin object
            GenericValue userLogin = (GenericValue) request.getSession().getAttribute("userLogin");
            if (userLogin == null) {
                userLogin = (GenericValue) request.getSession().getAttribute("autoUserLogin");
            }

            if (userLogin != null) {
                GenericValue ulUpdate = GenericValue.create(userLogin);
                ulUpdate.set("lastCurrencyUom", currencyUom);
                try {
                    ulUpdate.store();
                    userLogin.refreshFromCache();
                } catch (GenericEntityException e) {
                    Debug.logWarning(e, MODULE);
                }
            }
        }
        return "success";
    }

    public static String jsResponseFromRequest(HttpServletRequest request, HttpServletResponse response) {

        String fileName = request.getParameter("name");
        String script = ScriptLinkHelper.getScriptFromCache(request.getSession(), fileName);

        // return the JS String
        Writer out;
        try {

            // set the JS content type
            response.setContentType("application/javascript");
            // script.length is not reliable for unicode characters
            response.setContentLength(script.getBytes("UTF8").length);
            // return 404 if script is empty
            if (UtilValidate.isEmpty(script)) {
                response.setStatus(HttpServletResponse.SC_NOT_FOUND);
            }

            out = response.getWriter();
            out.write(script);
            out.flush();
        } catch (IOException e) {
            Debug.logError(e, MODULE);
            return "error";
        }
        return "success";
    }

    public static String jsonResponseFromRequestAttributes(HttpServletRequest request, HttpServletResponse response) {
        // pull out the service response from the request attribute

        Map<String, Object> attrMap = UtilHttp.getJSONAttributeMap(request);

        for (String ignoreAttr : IGNOREATTRS) {
            if (attrMap.containsKey(ignoreAttr)) {
                attrMap.remove(ignoreAttr);
            }
        }
        try {
            JSON json = JSON.from(attrMap);
            writeJSONtoResponse(json, request, response);
        } catch (IOException e) {
            return "error";
        }
        return "success";
    }

    private static void writeJSONtoResponse(JSON json, HttpServletRequest request, HttpServletResponse response)
            throws UnsupportedEncodingException {
        String jsonStr = json.toString();
        String httpMethod = request.getMethod();

        // This was added for security reason (OFBIZ-5409), you might need to remove the "//" prefix when handling the
        // JSON response
        // Though normally you simply have to access the data you want, so should not be annoyed by the "//" prefix
        if ("GET".equalsIgnoreCase(httpMethod)) {
            Debug.logWarning("for security reason (OFBIZ-5409) the '//' prefix was added handling the JSON response.  "
                    + "Normally you simply have to access the data you want, so should not be annoyed by the '//' prefix."
                    + "You might need to remove it if you use Ajax GET responses (not recommended)."
                    + "In case, the util.js scrpt is there to help you."
                    + "This can be customized in general.properties with the http.json.xssi.prefix property", MODULE);
            Delegator delegator = (Delegator) request.getAttribute("delegator");
            String xssiPrefix = EntityUtilProperties.getPropertyValue("general", "http.json.xssi.prefix", delegator);
            jsonStr = xssiPrefix + jsonStr;
        }

        // set the JSON content type
        response.setContentType("application/json");
        // jsonStr.length is not reliable for unicode characters
        response.setContentLength(jsonStr.getBytes("UTF8").length);

        // Set default security headers
        UtilHttp.setResponseBrowserDefaultSecurityHeaders(response, null);
        // return the JSON String
        Writer out;
        try {
            out = response.getWriter();
            out.write(jsonStr);
            out.flush();
        } catch (IOException e) {
            Debug.logError(e, MODULE);
        }
    }

    public static String getCaptcha(HttpServletRequest request, HttpServletResponse response) {
        try {
            Delegator delegator = (Delegator) request.getAttribute("delegator");
            final String captchaSizeConfigName = StringUtils.defaultIfEmpty(request.getParameter("captchaSize"),
                    "default");
            final String captchaSizeConfig = EntityUtilProperties.getPropertyValue("captcha",
                    "captcha." + captchaSizeConfigName, delegator);
            final String[] captchaSizeConfigs = captchaSizeConfig.split("\\|");
            // this is used to uniquely identify in the user session the attribute where the captcha code
            // for the last captcha for the form is stored
            final String captchaCodeId = StringUtils.defaultIfEmpty(request.getParameter("captchaCodeId"), "");

            final int fontSize = Integer.parseInt(captchaSizeConfigs[0]);
            final int height = Integer.parseInt(captchaSizeConfigs[1]);
            final int width = Integer.parseInt(captchaSizeConfigs[2]);
            final int charsToPrint = UtilProperties.getPropertyAsInteger("captcha", "captcha.code_length", 6);
            final char[] availableChars = EntityUtilProperties
                    .getPropertyValue("captcha", "captcha.characters", delegator).toCharArray();

            // It is possible to pass the font size, image width and height with the request as well
            Color backgroundColor = Color.gray;
            Color borderColor = Color.DARK_GRAY;
            Color textColor = Color.ORANGE;
            Color circleColor = new Color(160, 160, 160);
            Font textFont = new Font("Arial", Font.PLAIN, fontSize);
            int circlesToDraw = 6;
            float horizMargin = 20.0f;
            double rotationRange = 0.7; // in radians
            BufferedImage bufferedImage = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);

            Graphics2D g = (Graphics2D) bufferedImage.getGraphics();

            g.setColor(backgroundColor);
            g.fillRect(0, 0, width, height);

            // Generating some circles for background noise
            g.setColor(circleColor);
            for (int i = 0; i < circlesToDraw; i++) {
                int circleRadius = (int) (Math.random() * height / 2.0);
                int circleX = (int) (Math.random() * width - circleRadius);
                int circleY = (int) (Math.random() * height - circleRadius);
                g.drawOval(circleX, circleY, circleRadius * 2, circleRadius * 2);
            }
            g.setColor(textColor);
            g.setFont(textFont);

            FontMetrics fontMetrics = g.getFontMetrics();
            int maxAdvance = fontMetrics.getMaxAdvance();
            int fontHeight = fontMetrics.getHeight();

            String captchaCode = RandomStringUtils.random(6, availableChars);

            float spaceForLetters = -horizMargin * 2 + width;
            float spacePerChar = spaceForLetters / (charsToPrint - 1.0f);

            for (int i = 0; i < captchaCode.length(); i++) {

                // this is a separate canvas used for the character so that
                // we can rotate it independently
                int charWidth = fontMetrics.charWidth(captchaCode.charAt(i));
                int charDim = Math.max(maxAdvance, fontHeight);
                int halfCharDim = (charDim / 2);

                BufferedImage charImage = new BufferedImage(charDim, charDim, BufferedImage.TYPE_INT_ARGB);
                Graphics2D charGraphics = charImage.createGraphics();
                charGraphics.translate(halfCharDim, halfCharDim);
                double angle = (Math.random() - 0.5) * rotationRange;
                charGraphics.transform(AffineTransform.getRotateInstance(angle));
                charGraphics.translate(-halfCharDim, -halfCharDim);
                charGraphics.setColor(textColor);
                charGraphics.setFont(textFont);

                int charX = (int) (0.5 * charDim - 0.5 * charWidth);
                charGraphics.drawString("" + captchaCode.charAt(i), charX, (charDim - fontMetrics.getAscent()) / 2 + fontMetrics.getAscent());

                float x = horizMargin + spacePerChar * (i) - charDim / 2.0f;
                int y = ((height - charDim) / 2);

                g.drawImage(charImage, (int) x, y, charDim, charDim, null, null);

                charGraphics.dispose();
            }
            // Drawing the image border
            g.setColor(borderColor);
            g.drawRect(0, 0, width - 1, height - 1);
            g.dispose();
            response.setContentType("image/jpeg");
            ImageIO.write(bufferedImage, "jpg", response.getOutputStream());
            HttpSession session = request.getSession();
            Map<String, String> captchaCodeMap = UtilGenerics.cast(session.getAttribute("_CAPTCHA_CODE_"));
            if (captchaCodeMap == null) {
                captchaCodeMap = new HashMap<>();
                session.setAttribute("_CAPTCHA_CODE_", captchaCodeMap);
            }
            captchaCodeMap.put(captchaCodeId, captchaCode);
        } catch (IOException | IllegalArgumentException | IllegalStateException ioe) {
            Debug.logError(ioe.getMessage(), MODULE);
        }
        return "success";
    }

    public static String loadJWT(HttpServletRequest request, HttpServletResponse response)
            throws UnsupportedEncodingException {
        Delegator delegator = (Delegator) request.getAttribute("delegator");
        Map<String, String> types = new HashMap<>();
        String securedUserLoginId = LoginWorker.getSecuredUserLoginId(request);
        if (securedUserLoginId != null) {
            types.put("userLoginId", securedUserLoginId);
            // 30 seconds seems plenty enough OOTB to compensate for possible time difference
            // If you cross issue with this value you should use the same NTP server for both sides
            // Custom projects might want set a lower value for security reason
            int ttlSeconds = (int) Long.parseLong(EntityUtilProperties.getPropertyValue("security",
                    "security.jwt.token.expireTime", "30", delegator));
            String token = JWTManager.createJwt(delegator, types, ttlSeconds);
            writeJSONtoResponse(JSON.from(token), request, response);
        } else {
            Debug.logWarning("No securedUserLoginId cookie was found for this application", MODULE);
        }
        return "success";
    }

    /**
     * Open the source file. Only when widget.dev.namedBorder=SOURCE
     * @param request
     * @param response
     * @return
     */
    public static String openSourceFile(HttpServletRequest request, HttpServletResponse response) {
        ModelWidget.NamedBorderType namedBorderType = ModelWidget.widgetNamedBorderType();
        if (namedBorderType == ModelWidget.NamedBorderType.SOURCE) {
            String sourceLocation = request.getParameter("sourceLocation");
            if (UtilValidate.isNotEmpty(sourceLocation) && sourceLocation.startsWith("component:")) {
                try {
                    // find absolute path of file
                    URL sourceFileUrl = null;
                    String fragment = "";
                    if (sourceLocation.contains("#")) {
                        int indexOfHash = sourceLocation.indexOf("#");
                        sourceFileUrl = FlexibleLocation.resolveLocation(sourceLocation.substring(0, indexOfHash));
                        fragment = sourceLocation.substring(indexOfHash + 1);
                    } else {
                        sourceFileUrl = FlexibleLocation.resolveLocation(sourceLocation);
                    }
                    String platformSpecificPath = sourceFileUrl.getFile();
                    // ensure file separator in location is correct
                    if (!platformSpecificPath.contains(File.separator) && "\\".equals(File.separator)) {
                        platformSpecificPath = platformSpecificPath.replace("/", "\\");
                    }
                    // get line number
                    int lineNumber = 1;
                    if (UtilValidate.isNotEmpty(fragment)) {
                        try (LineNumberReader lnr = new LineNumberReader(new FileReader(platformSpecificPath))) {
                            String line;
                            while ((line = lnr.readLine()) != null) {
                                if (line.matches(".*name=\"" + fragment + "\".*")) {
                                    lineNumber = lnr.getLineNumber();
                                    break;
                                }
                            }
                        } catch (IOException e) {
                            Debug.logError(e, MODULE);
                        }
                    }
                    // prepare content map for string expansion
                    Map<String, Object> sourceMap = new HashMap<>();
                    sourceMap.put("sourceLocation", platformSpecificPath);
                    sourceMap.put("lineNumber", lineNumber);
                    // get command to run
                    String cmdTemplate = UtilProperties.getPropertyValue("widget", "widget.dev.cmd.openSourceFile");
                    String cmd = (String) FlexibleStringExpander.getInstance(cmdTemplate).expand(sourceMap);
                    // run command
                    Debug.logInfo("Run command: " + cmd, MODULE);
                    Process process = Runtime.getRuntime().exec(cmd);
                    // print result
                    BufferedReader reader = new BufferedReader(new InputStreamReader(process.getInputStream()));
                    String line = "";
                    while ((line = reader.readLine()) != null) {
                        Debug.logInfo(line, MODULE);
                    }
                    return "success";
                } catch (IOException e) {
                    Debug.logError(e, MODULE);
                }
            }
        }
        return "error";
    }

}
