/*
 * Copyright (c) 2008, 2018, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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package com.sun.tools.javac.util;

import java.nio.file.Path;
import java.util.Arrays;
import java.util.Collection;
import java.util.EnumSet;
import java.util.HashMap;
import java.util.Locale;
import java.util.Map;
import java.util.Set;

import javax.tools.JavaFileObject;

import com.sun.tools.javac.api.DiagnosticFormatter;
import com.sun.tools.javac.api.DiagnosticFormatter.Configuration.DiagnosticPart;
import com.sun.tools.javac.api.DiagnosticFormatter.Configuration.MultilineLimit;
import com.sun.tools.javac.api.DiagnosticFormatter.PositionKind;
import com.sun.tools.javac.api.Formattable;
import com.sun.tools.javac.code.Lint.LintCategory;
import com.sun.tools.javac.code.Printer;
import com.sun.tools.javac.code.Source;
import com.sun.tools.javac.code.Symbol;
import com.sun.tools.javac.code.Type;
import com.sun.tools.javac.code.Type.CapturedType;
import com.sun.tools.javac.file.PathFileObject;
import com.sun.tools.javac.jvm.Profile;
import com.sun.tools.javac.jvm.Target;
import com.sun.tools.javac.main.Option;
import com.sun.tools.javac.tree.JCTree.*;
import com.sun.tools.javac.tree.Pretty;

import static com.sun.tools.javac.util.JCDiagnostic.DiagnosticType.*;

This abstract class provides a basic implementation of the functionalities that should be provided
by any formatter used by javac. Among the main features provided by AbstractDiagnosticFormatter are:

 
 Provides a standard implementation of the visitor-like methods defined in the interface DiagnisticFormatter.
 Those implementations are specifically targeting JCDiagnostic objects.
 
 Provides basic support for i18n and a method for executing all locale-dependent conversions
 
 Provides the formatting logic for rendering the arguments of a JCDiagnostic object.

This is NOT part of any supported API.
If you write code that depends on this, you do so at your own risk.
This code and its internal interfaces are subject to change or
deletion without notice.
/**
 * This abstract class provides a basic implementation of the functionalities that should be provided
 * by any formatter used by javac. Among the main features provided by AbstractDiagnosticFormatter are:
 *
 * <ul>
 *  <li> Provides a standard implementation of the visitor-like methods defined in the interface DiagnisticFormatter.
 *  Those implementations are specifically targeting JCDiagnostic objects.
 *  <li> Provides basic support for i18n and a method for executing all locale-dependent conversions
 *  <li> Provides the formatting logic for rendering the arguments of a JCDiagnostic object.
 * </ul>
 *
 * <p><b>This is NOT part of any supported API.
 * If you write code that depends on this, you do so at your own risk.
 * This code and its internal interfaces are subject to change or
 * deletion without notice.</b>
 */
public abstract class AbstractDiagnosticFormatter implements DiagnosticFormatter<JCDiagnostic> {

    
JavacMessages object used by this formatter for i18n.
/**
     * JavacMessages object used by this formatter for i18n.
     */
    protected JavacMessages messages;

    
Configuration object used by this formatter
/**
     * Configuration object used by this formatter
     */
    private SimpleConfiguration config;

    
Current depth level of the disgnostic being formatted
(!= 0 for subdiagnostics)
/**
     * Current depth level of the disgnostic being formatted
     * (!= 0 for subdiagnostics)
     */
    protected int depth = 0;

    
All captured types that have been encountered during diagnostic formatting.
This info is used by the FormatterPrinter in order to print friendly unique
ids for captured types
/**
     * All captured types that have been encountered during diagnostic formatting.
     * This info is used by the FormatterPrinter in order to print friendly unique
     * ids for captured types
     */
    private List<Type> allCaptured = List.nil();

    
Initialize an AbstractDiagnosticFormatter by setting its JavacMessages object.
Params:
messages – /**
     * Initialize an AbstractDiagnosticFormatter by setting its JavacMessages object.
     * @param messages
     */
    protected AbstractDiagnosticFormatter(JavacMessages messages, SimpleConfiguration config) {
        this.messages = messages;
        this.config = config;
    }

    public String formatKind(JCDiagnostic d, Locale l) {
        switch (d.getType()) {
            case FRAGMENT: return "";
            case NOTE:     return localize(l, "compiler.note.note");
            case WARNING:  return localize(l, "compiler.warn.warning");
            case ERROR:    return localize(l, "compiler.err.error");
            default:
                throw new AssertionError("Unknown diagnostic type: " + d.getType());
        }
    }

    @Override
    public String format(JCDiagnostic d, Locale locale) {
        allCaptured = List.nil();
        return formatDiagnostic(d, locale);
    }

    protected abstract String formatDiagnostic(JCDiagnostic d, Locale locale);

    public String formatPosition(JCDiagnostic d, PositionKind pk,Locale l) {
        Assert.check(d.getPosition() != Position.NOPOS);
        return String.valueOf(getPosition(d, pk));
    }
    //where
    private long getPosition(JCDiagnostic d, PositionKind pk) {
        switch (pk) {
            case START: return d.getIntStartPosition();
            case END: return d.getIntEndPosition();
            case LINE: return d.getLineNumber();
            case COLUMN: return d.getColumnNumber();
            case OFFSET: return d.getIntPosition();
            default:
                throw new AssertionError("Unknown diagnostic position: " + pk);
        }
    }

    public String formatSource(JCDiagnostic d, boolean fullname, Locale l) {
        JavaFileObject fo = d.getSource();
        if (fo == null)
            throw new IllegalArgumentException(); // d should have source set
        if (fullname)
            return fo.getName();
        else if (fo instanceof PathFileObject)
            return ((PathFileObject) fo).getShortName();
        else
            return PathFileObject.getSimpleName(fo);
    }

    
Format the arguments of a given diagnostic.
Params:
d – diagnostic whose arguments are to be formatted
l – locale object to be used for i18n
Returns:
a Collection whose elements are the formatted arguments of the diagnostic/**
     * Format the arguments of a given diagnostic.
     *
     * @param d diagnostic whose arguments are to be formatted
     * @param l locale object to be used for i18n
     * @return a Collection whose elements are the formatted arguments of the diagnostic
     */
    protected Collection<String> formatArguments(JCDiagnostic d, Locale l) {
        ListBuffer<String> buf = new ListBuffer<>();
        for (Object o : d.getArgs()) {
           buf.append(formatArgument(d, o, l));
        }
        return buf.toList();
    }

    
Format a single argument of a given diagnostic.
Params:
d – diagnostic whose argument is to be formatted
arg – argument to be formatted
l – locale object to be used for i18n
Returns:
string representation of the diagnostic argument/**
     * Format a single argument of a given diagnostic.
     *
     * @param d diagnostic whose argument is to be formatted
     * @param arg argument to be formatted
     * @param l locale object to be used for i18n
     * @return string representation of the diagnostic argument
     */
    protected String formatArgument(JCDiagnostic d, Object arg, Locale l) {
        if (arg instanceof JCDiagnostic) {
            String s = null;
            depth++;
            try {
                s = formatMessage((JCDiagnostic)arg, l);
            }
            finally {
                depth--;
            }
            return s;
        }
        else if (arg instanceof JCExpression) {
            return expr2String((JCExpression)arg);
        }
        else if (arg instanceof Iterable<?> && !(arg instanceof Path)) {
            return formatIterable(d, (Iterable<?>)arg, l);
        }
        else if (arg instanceof Type) {
            return printer.visit((Type)arg, l);
        }
        else if (arg instanceof Symbol) {
            return printer.visit((Symbol)arg, l);
        }
        else if (arg instanceof JavaFileObject) {
            return ((JavaFileObject)arg).getName();
        }
        else if (arg instanceof Profile) {
            return ((Profile)arg).name;
        }
        else if (arg instanceof Option) {
            return ((Option)arg).primaryName;
        }
        else if (arg instanceof Formattable) {
            return ((Formattable)arg).toString(l, messages);
        }
        else if (arg instanceof Target) {
            return ((Target)arg).name;
        }
        else if (arg instanceof Source) {
            return ((Source)arg).name;
        }
        else if (arg instanceof Tag) {
            return messages.getLocalizedString(l, "compiler.misc.tree.tag." +
                                                  StringUtils.toLowerCase(((Tag) arg).name()));
        }
        else {
            return String.valueOf(arg);
        }
    }
    //where
            private String expr2String(JCExpression tree) {
                switch(tree.getTag()) {
                    case PARENS:
                        return expr2String(((JCParens)tree).expr);
                    case LAMBDA:
                    case REFERENCE:
                    case CONDEXPR:
                        return Pretty.toSimpleString(tree);
                    default:
                        Assert.error("unexpected tree kind " + tree.getKind());
                        return null;
                }
            }

    
Format an iterable argument of a given diagnostic.
Params:
d – diagnostic whose argument is to be formatted
it – iterable argument to be formatted
l – locale object to be used for i18n
Returns:
string representation of the diagnostic iterable argument/**
     * Format an iterable argument of a given diagnostic.
     *
     * @param d diagnostic whose argument is to be formatted
     * @param it iterable argument to be formatted
     * @param l locale object to be used for i18n
     * @return string representation of the diagnostic iterable argument
     */
    protected String formatIterable(JCDiagnostic d, Iterable<?> it, Locale l) {
        StringBuilder sbuf = new StringBuilder();
        String sep = "";
        for (Object o : it) {
            sbuf.append(sep);
            sbuf.append(formatArgument(d, o, l));
            sep = ",";
        }
        return sbuf.toString();
    }

    
Format all the subdiagnostics attached to a given diagnostic.
Params:
d – diagnostic whose subdiagnostics are to be formatted
l – locale object to be used for i18n
Returns:
list of all string representations of the subdiagnostics/**
     * Format all the subdiagnostics attached to a given diagnostic.
     *
     * @param d diagnostic whose subdiagnostics are to be formatted
     * @param l locale object to be used for i18n
     * @return list of all string representations of the subdiagnostics
     */
    protected List<String> formatSubdiagnostics(JCDiagnostic d, Locale l) {
        List<String> subdiagnostics = List.nil();
        int maxDepth = config.getMultilineLimit(MultilineLimit.DEPTH);
        if (maxDepth == -1 || depth < maxDepth) {
            depth++;
            try {
                int maxCount = config.getMultilineLimit(MultilineLimit.LENGTH);
                int count = 0;
                for (JCDiagnostic d2 : d.getSubdiagnostics()) {
                    if (maxCount == -1 || count < maxCount) {
                        subdiagnostics = subdiagnostics.append(formatSubdiagnostic(d, d2, l));
                        count++;
                    }
                    else
                        break;
                }
            }
            finally {
                depth--;
            }
        }
        return subdiagnostics;
    }

    
Format a subdiagnostics attached to a given diagnostic.
Params:
parent – multiline diagnostic whose subdiagnostics is to be formatted
sub – subdiagnostic to be formatted
l – locale object to be used for i18n
Returns:
string representation of the subdiagnostics/**
     * Format a subdiagnostics attached to a given diagnostic.
     *
     * @param parent multiline diagnostic whose subdiagnostics is to be formatted
     * @param sub subdiagnostic to be formatted
     * @param l locale object to be used for i18n
     * @return string representation of the subdiagnostics
     */
    protected String formatSubdiagnostic(JCDiagnostic parent, JCDiagnostic sub, Locale l) {
        return formatMessage(sub, l);
    }

    
Format the faulty source code line and point to the error.
 @param d The diagnostic for which the error line should be printed
/** Format the faulty source code line and point to the error.
     *  @param d The diagnostic for which the error line should be printed
     */
    protected String formatSourceLine(JCDiagnostic d, int nSpaces) {
        StringBuilder buf = new StringBuilder();
        DiagnosticSource source = d.getDiagnosticSource();
        int pos = d.getIntPosition();
        if (d.getIntPosition() == Position.NOPOS)
            throw new AssertionError();
        String line = (source == null ? null : source.getLine(pos));
        if (line == null)
            return "";
        buf.append(indent(line, nSpaces));
        int col = source.getColumnNumber(pos, false);
        if (config.isCaretEnabled()) {
            buf.append("\n");
            for (int i = 0; i < col - 1; i++)  {
                buf.append((line.charAt(i) == '\t') ? "\t" : " ");
            }
            buf.append(indent("^", nSpaces));
        }
        return buf.toString();
    }

    protected String formatLintCategory(JCDiagnostic d, Locale l) {
        LintCategory lc = d.getLintCategory();
        if (lc == null)
            return "";
        return localize(l, "compiler.warn.lintOption", lc.option);
    }

    
Converts a String into a locale-dependent representation accordingly to a given locale.
Params:
l – locale object to be used for i18n
key – locale-independent key used for looking up in a resource file
args – localization arguments
Returns:
a locale-dependent string/**
     * Converts a String into a locale-dependent representation accordingly to a given locale.
     *
     * @param l locale object to be used for i18n
     * @param key locale-independent key used for looking up in a resource file
     * @param args localization arguments
     * @return a locale-dependent string
     */
    protected String localize(Locale l, String key, Object... args) {
        return messages.getLocalizedString(l, key, args);
    }

    public boolean displaySource(JCDiagnostic d) {
        return config.getVisible().contains(DiagnosticPart.SOURCE) &&
                d.getType() != FRAGMENT &&
                d.getIntPosition() != Position.NOPOS;
    }

    public boolean isRaw() {
        return false;
    }

    
Creates a string with a given amount of empty spaces. Useful for
indenting the text of a diagnostic message.
Params:
nSpaces – the amount of spaces to be added to the result string
Returns:
the indentation string/**
     * Creates a string with a given amount of empty spaces. Useful for
     * indenting the text of a diagnostic message.
     *
     * @param nSpaces the amount of spaces to be added to the result string
     * @return the indentation string
     */
    protected String indentString(int nSpaces) {
        String spaces = "                        ";
        if (nSpaces <= spaces.length())
            return spaces.substring(0, nSpaces);
        else {
            StringBuilder buf = new StringBuilder();
            for (int i = 0 ; i < nSpaces ; i++)
                buf.append(" ");
            return buf.toString();
        }
    }

    
Indent a string by prepending a given amount of empty spaces to each line
of the string.
Params:
s – the string to be indented
nSpaces – the amount of spaces that should be prepended to each line
of the string
Returns:
an indented string/**
     * Indent a string by prepending a given amount of empty spaces to each line
     * of the string.
     *
     * @param s the string to be indented
     * @param nSpaces the amount of spaces that should be prepended to each line
     * of the string
     * @return an indented string
     */
    protected String indent(String s, int nSpaces) {
        String indent = indentString(nSpaces);
        StringBuilder buf = new StringBuilder();
        String nl = "";
        for (String line : s.split("\n")) {
            buf.append(nl);
            buf.append(indent + line);
            nl = "\n";
        }
        return buf.toString();
    }

    public SimpleConfiguration getConfiguration() {
        return config;
    }

    static public class SimpleConfiguration implements Configuration {

        protected Map<MultilineLimit, Integer> multilineLimits;
        protected EnumSet<DiagnosticPart> visibleParts;
        protected boolean caretEnabled;

        public SimpleConfiguration(Set<DiagnosticPart> parts) {
            multilineLimits = new HashMap<>();
            setVisible(parts);
            setMultilineLimit(MultilineLimit.DEPTH, -1);
            setMultilineLimit(MultilineLimit.LENGTH, -1);
            setCaretEnabled(true);
        }

        @SuppressWarnings("fallthrough")
        public SimpleConfiguration(Options options, Set<DiagnosticPart> parts) {
            this(parts);
            String showSource = null;
            if ((showSource = options.get("diags.showSource")) != null) {
                if (showSource.equals("true"))
                    setVisiblePart(DiagnosticPart.SOURCE, true);
                else if (showSource.equals("false"))
                    setVisiblePart(DiagnosticPart.SOURCE, false);
            }
            String diagOpts = options.get("diags.formatterOptions");
            if (diagOpts != null) {//override -XDshowSource
                Collection<String> args = Arrays.asList(diagOpts.split(","));
                if (args.contains("short")) {
                    setVisiblePart(DiagnosticPart.DETAILS, false);
                    setVisiblePart(DiagnosticPart.SUBDIAGNOSTICS, false);
                }
                if (args.contains("source"))
                    setVisiblePart(DiagnosticPart.SOURCE, true);
                if (args.contains("-source"))
                    setVisiblePart(DiagnosticPart.SOURCE, false);
            }
            String multiPolicy = null;
            if ((multiPolicy = options.get("diags.multilinePolicy")) != null) {
                if (multiPolicy.equals("disabled"))
                    setVisiblePart(DiagnosticPart.SUBDIAGNOSTICS, false);
                else if (multiPolicy.startsWith("limit:")) {
                    String limitString = multiPolicy.substring("limit:".length());
                    String[] limits = limitString.split(":");
                    try {
                        switch (limits.length) {
                            case 2: {
                                if (!limits[1].equals("*"))
                                    setMultilineLimit(MultilineLimit.DEPTH, Integer.parseInt(limits[1]));
                            }
                            case 1: {
                                if (!limits[0].equals("*"))
                                    setMultilineLimit(MultilineLimit.LENGTH, Integer.parseInt(limits[0]));
                            }
                        }
                    }
                    catch(NumberFormatException ex) {
                        setMultilineLimit(MultilineLimit.DEPTH, -1);
                        setMultilineLimit(MultilineLimit.LENGTH, -1);
                    }
                }
            }
            String showCaret = null;
            if (((showCaret = options.get("diags.showCaret")) != null) &&
                showCaret.equals("false"))
                    setCaretEnabled(false);
            else
                setCaretEnabled(true);
        }

        public int getMultilineLimit(MultilineLimit limit) {
            return multilineLimits.get(limit);
        }

        public EnumSet<DiagnosticPart> getVisible() {
            return EnumSet.copyOf(visibleParts);
        }

        public void setMultilineLimit(MultilineLimit limit, int value) {
            multilineLimits.put(limit, value < -1 ? -1 : value);
        }


        public void setVisible(Set<DiagnosticPart> diagParts) {
            visibleParts = EnumSet.copyOf(diagParts);
        }

        public void setVisiblePart(DiagnosticPart diagParts, boolean enabled) {
            if (enabled)
                visibleParts.add(diagParts);
            else
                visibleParts.remove(diagParts);
        }

        
Shows a '^' sign under the source line displayed by the formatter
(if applicable).
Params:
caretEnabled – if true enables caret/**
         * Shows a '^' sign under the source line displayed by the formatter
         * (if applicable).
         *
         * @param caretEnabled if true enables caret
         */
        public void setCaretEnabled(boolean caretEnabled) {
            this.caretEnabled = caretEnabled;
        }

        
Tells whether the caret display is active or not.
Returns:
true if the caret is enabled/**
         * Tells whether the caret display is active or not.
         *
         * @return true if the caret is enabled
         */
        public boolean isCaretEnabled() {
            return caretEnabled;
        }
    }

    public Printer getPrinter() {
        return printer;
    }

    public void setPrinter(Printer printer) {
        this.printer = printer;
    }

    
An enhanced printer for formatting types/symbols used by
AbstractDiagnosticFormatter. Provides alternate numbering of captured
types (they are numbered starting from 1 on each new diagnostic, instead
of relying on the underlying hashcode() method which generates unstable
output). Also detects cycles in wildcard messages (e.g. if the wildcard
type referred by a given captured type C contains C itself) which might
lead to infinite loops.
/**
     * An enhanced printer for formatting types/symbols used by
     * AbstractDiagnosticFormatter. Provides alternate numbering of captured
     * types (they are numbered starting from 1 on each new diagnostic, instead
     * of relying on the underlying hashcode() method which generates unstable
     * output). Also detects cycles in wildcard messages (e.g. if the wildcard
     * type referred by a given captured type C contains C itself) which might
     * lead to infinite loops.
     */
    protected Printer printer = new Printer() {

        @Override
        protected String localize(Locale locale, String key, Object... args) {
            return AbstractDiagnosticFormatter.this.localize(locale, key, args);
        }
        @Override
        protected String capturedVarId(CapturedType t, Locale locale) {
            return "" + (allCaptured.indexOf(t) + 1);
        }
        @Override
        public String visitCapturedType(CapturedType t, Locale locale) {
            if (!allCaptured.contains(t)) {
                allCaptured = allCaptured.append(t);
            }
            return super.visitCapturedType(t, locale);
        }
    };
}