1/*
2 * Copyright (C) 2013 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package com.android.inputmethod.keyboard.internal;
18
19import com.android.inputmethod.latin.Constants;
20
21import android.text.TextUtils;
22
23/**
24 * The string parser of codesArray specification for <GridRows />. The attribute codesArray is an
25 * array of string.
26 * Each element of the array defines a key label by specifying a code point as a hexadecimal string.
27 * A key label may consist of multiple code points separated by comma.
28 * Each element of the array optionally can have an output text definition after vertical bar
29 * marker. An output text may consist of multiple code points separated by comma.
30 * The format of the codesArray element should be:
31 * <pre>
32 *   codePointInHex[,codePoint2InHex]*(|outputTextCodePointInHex[,outputTextCodePoint2InHex]*)?
33 * </pre>
34 */
35// TODO: Write unit tests for this class.
36public final class CodesArrayParser {
37    // Constants for parsing.
38    private static final char COMMA = ',';
39    private static final String VERTICAL_BAR_STRING = "\\|";
40    private static final String COMMA_STRING = ",";
41    private static final int BASE_HEX = 16;
42
43    private CodesArrayParser() {
44     // This utility class is not publicly instantiable.
45    }
46
47    private static String getLabelSpec(final String codesArraySpec) {
48        final String[] strs = codesArraySpec.split(VERTICAL_BAR_STRING, -1);
49        if (strs.length <= 1) {
50            return codesArraySpec;
51        }
52        return strs[0];
53    }
54
55    public static String parseLabel(final String codesArraySpec) {
56        final String labelSpec = getLabelSpec(codesArraySpec);
57        final StringBuilder sb = new StringBuilder();
58        for (final String codeInHex : labelSpec.split(COMMA_STRING)) {
59            final int codePoint = Integer.parseInt(codeInHex, BASE_HEX);
60            sb.appendCodePoint(codePoint);
61        }
62        return sb.toString();
63    }
64
65    private static String getCodeSpec(final String codesArraySpec) {
66        final String[] strs = codesArraySpec.split(VERTICAL_BAR_STRING, -1);
67        if (strs.length <= 1) {
68            return codesArraySpec;
69        }
70        return TextUtils.isEmpty(strs[1]) ? strs[0] : strs[1];
71    }
72
73    // codesArraySpec consists of:
74    // <label>|<code0>,<code1>,...|<minSupportSdkVersion>
75    public static int getMinSupportSdkVersion(final String codesArraySpec) {
76        final String[] strs = codesArraySpec.split(VERTICAL_BAR_STRING, -1);
77        if (strs.length <= 2) {
78            return 0;
79        }
80        try {
81            return Integer.parseInt(strs[2]);
82        } catch (NumberFormatException e) {
83            return 0;
84        }
85    }
86
87    public static int parseCode(final String codesArraySpec) {
88        final String codeSpec = getCodeSpec(codesArraySpec);
89        if (codeSpec.indexOf(COMMA) < 0) {
90            return Integer.parseInt(codeSpec, BASE_HEX);
91        }
92        return Constants.CODE_OUTPUT_TEXT;
93    }
94
95    public static String parseOutputText(final String codesArraySpec) {
96        final String codeSpec = getCodeSpec(codesArraySpec);
97        if (codeSpec.indexOf(COMMA) < 0) {
98            return null;
99        }
100        final StringBuilder sb = new StringBuilder();
101        for (final String codeInHex : codeSpec.split(COMMA_STRING)) {
102            final int codePoint = Integer.parseInt(codeInHex, BASE_HEX);
103            sb.appendCodePoint(codePoint);
104        }
105        return sb.toString();
106    }
107}
108