/*

 * Copyright (c) 2016, 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

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

package com.sun.tools.jdeprscan;

import java.io.BufferedReader;

import java.io.IOException;

import java.nio.file.Files;

import java.nio.file.Paths;

import java.util.ArrayList;

import java.util.Arrays;

import java.util.Formatter;

import java.util.HashMap;

import java.util.List;

import java.util.Locale;

import java.util.Map;

import java.util.Set;

import javax.lang.model.element.ElementKind;

/**

 * A database of deprecations (APIs declared to be deprecated),

 * loaded from a JDK or from a class library.

 */

public class DeprDB {

    /**

     * Deprecated types.

     * A map from deprecated type names to DeprData values.

     * Types include classes, interfaces, enums, and annotation types.

     */

    final Map<String, DeprData> types = new HashMap<>();

    /**

     * Deprecated methods. Key is type name, value is map from method

     * signatures in the form "methodname(parms)ret" to DeprData value.

     */

    final Map<String, Map<String, DeprData>> methods = new HashMap<>();

    /**

     * Deprecated fields. Key is type name, value is map from field name

     * to forRemoval value.

     */

    final Map<String, Map<String, DeprData>> fields = new HashMap<>();

    /**

     * Set of valid ElementKind strings.

     */

    static final Set<String> validElementKinds =

        Set.of(Arrays.stream(ElementKind.values())

                     .map(ElementKind::toString)

                     .toArray(String[]::new));

    private DeprDB() { }

    public static List<DeprData> loadFromFile(String filename) throws IOException {

        List<DeprData> list = new ArrayList<>();

        exit:

        try (final BufferedReader br = Files.newBufferedReader(Paths.get(filename))) {

            String line = br.readLine();

            if (line == null || !line.equals("#jdepr1")) {

                System.out.printf("ERROR: invalid first line %s%n", line);

                break exit;

            }

            while ((line = br.readLine()) != null) {

                if (line.startsWith("#")) {

                    continue;

                }

                List<String> tokens = CSV.split(line);

                if (tokens.size() != 5) {

                    System.out.printf("ERROR: %s%n", line);

                    continue;

                }

                // kind,typeName,descOrName,since,forRemoval

                String kindStr = tokens.get(0);

                String type = tokens.get(1);

                String detail = tokens.get(2);

                String since = tokens.get(3);

                boolean forRemoval = Boolean.parseBoolean(tokens.get(4));

                ElementKind kind;

                if (validElementKinds.contains(kindStr)) {

                    kind = ElementKind.valueOf(kindStr);

                } else {

                    System.out.printf("ERROR: invalid element kind %s%n", kindStr);

                    continue;

                }

                DeprData data = new DeprData(kind, /*TypeElement*/null, type, detail, since, forRemoval);

                list.add(data);

            }

        }

        return list;

    }

    public static DeprDB loadFromList(List<DeprData> deprList) {

        DeprDB db = new DeprDB();

        for (DeprData dd : deprList) {

            switch (dd.kind) {

                case CLASS:

                case INTERFACE:

                case ENUM:

                case ANNOTATION_TYPE:

                    db.types.put(dd.typeName, dd);

                    break;

                case METHOD:

                case CONSTRUCTOR:

                    db.methods.computeIfAbsent(dd.typeName, k -> new HashMap<>())

                              .put(dd.nameSig, dd);

                    break;

                case ENUM_CONSTANT:

                case FIELD:

                    db.fields.computeIfAbsent(dd.typeName, k -> new HashMap<>())

                             .put(dd.nameSig, dd);

                    break;

            }

        }

        return db;

    }

    @Override

    public String toString() {

        StringBuilder sb = new StringBuilder();

        Formatter f = new Formatter(sb, Locale.US);

        f.format("=== Types ===%n");

        f.format("%s%n", types.toString());

        f.format("=== Methods ===%n");

        f.format("%s%n", methods.toString());

        f.format("=== Fields ===%n");

        f.format("%s%n", fields.toString());

        return sb.toString();

    }

    public DeprData getTypeDeprecated(String typeName) {

        return types.get(typeName);

    }

    public DeprData getMethodDeprecated(String typeName, String methodName, String type) {

        Map<String, DeprData> m = methods.get(typeName);

        if (m == null) {

            return null;

        }

        return m.get(methodName + type);

    }

    public DeprData getFieldDeprecated(String typeName, String fieldName) {

        Map<String, DeprData> f = fields.get(typeName);

        if (f == null) {

            return null;

        }

        return f.get(fieldName);

    }

}