1/*
2 * Copyright (C) 2015 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 android.databinding.tool.expr;
18
19import android.databinding.tool.reflection.ModelAnalyzer;
20import android.databinding.tool.reflection.ModelClass;
21import android.databinding.tool.solver.ExecutionPath;
22import android.databinding.tool.writer.KCode;
23
24import com.google.common.collect.Lists;
25
26import java.util.ArrayList;
27import java.util.List;
28
29public class BracketExpr extends Expr {
30
31    public enum BracketAccessor {
32        ARRAY,
33        LIST,
34        MAP,
35    }
36
37    private BracketAccessor mAccessor;
38
39    BracketExpr(Expr target, Expr arg) {
40        super(target, arg);
41    }
42
43    @Override
44    protected ModelClass resolveType(ModelAnalyzer modelAnalyzer) {
45        ModelClass targetType = getTarget().getResolvedType();
46        if (targetType.isArray()) {
47            mAccessor = BracketAccessor.ARRAY;
48        } else if (targetType.isList()) {
49            mAccessor = BracketAccessor.LIST;
50        } else if (targetType.isMap()) {
51            mAccessor = BracketAccessor.MAP;
52        } else {
53            throw new IllegalArgumentException("Cannot determine variable type used in [] " +
54                    "expression. Cast the value to List, Map, " +
55                    "or array. Type detected: " + targetType.toJavaCode());
56        }
57        return targetType.getComponentType();
58    }
59
60    @Override
61    public List<ExecutionPath> toExecutionPath(List<ExecutionPath> paths) {
62        final List<ExecutionPath> targetPaths = getTarget().toExecutionPath(paths);
63        // after this, we need a null check.
64        List<ExecutionPath> result = new ArrayList<ExecutionPath>();
65        if (getTarget() instanceof StaticIdentifierExpr) {
66            result.addAll(toExecutionPathInOrder(paths, getTarget()));
67        } else {
68            for (ExecutionPath path : targetPaths) {
69                Expr cmp = getModel().comparison("!=", getTarget(),
70                        getModel().symbol("null", Object.class));
71                path.addPath(cmp);
72                final ExecutionPath subPath = path.addBranch(cmp, true);
73                if (subPath != null) {
74                    final List<ExecutionPath> argPath = getArg().toExecutionPath(subPath);
75                    result.addAll(addJustMeToExecutionPath(argPath));
76                }
77            }
78        }
79        return result;
80    }
81
82    @Override
83    protected List<Dependency> constructDependencies() {
84        final List<Dependency> dependencies = constructDynamicChildrenDependencies();
85        for (Dependency dependency : dependencies) {
86            if (dependency.getOther() == getTarget()) {
87                dependency.setMandatory(true);
88            }
89        }
90        return dependencies;
91    }
92
93    protected String computeUniqueKey() {
94        final String targetKey = getTarget().computeUniqueKey();
95        return join(targetKey, "$", getArg().computeUniqueKey(), "$");
96    }
97
98    @Override
99    public String getInvertibleError() {
100        return null;
101    }
102
103    public Expr getTarget() {
104        return getChildren().get(0);
105    }
106
107    public Expr getArg() {
108        return getChildren().get(1);
109    }
110
111    public BracketAccessor getAccessor() {
112        return mAccessor;
113    }
114
115    public boolean argCastsInteger() {
116        return mAccessor != BracketAccessor.MAP && getArg().getResolvedType().isObject();
117    }
118
119    @Override
120    protected KCode generateCode() {
121        String cast = argCastsInteger() ? "(Integer) " : "";
122        switch (getAccessor()) {
123            case ARRAY: {
124                return new KCode().
125                        app("getFromArray(", getTarget().toCode()).
126                        app(", ").
127                        app(cast, getArg().toCode()).app(")");
128            }
129            case LIST: {
130                ModelClass listType = ModelAnalyzer.getInstance().findClass(java.util.List.class).
131                        erasure();
132                ModelClass targetType = getTarget().getResolvedType().erasure();
133                if (listType.isAssignableFrom(targetType)) {
134                    return new KCode().
135                            app("getFromList(", getTarget().toCode()).
136                            app(", ").
137                            app(cast, getArg().toCode()).
138                            app(")");
139                } else {
140                    return new KCode().
141                            app("", getTarget().toCode()).
142                            app(".get(").
143                            app(cast, getArg().toCode()).
144                            app(")");
145                }
146            }
147            case MAP:
148                return new KCode().
149                        app("", getTarget().toCode()).
150                        app(".get(", getArg().toCode()).
151                        app(")");
152        }
153        throw new IllegalStateException("Invalid BracketAccessor type");
154    }
155
156    @Override
157    public Expr generateInverse(ExprModel model, Expr value, String bindingClassName) {
158        Expr arg = getArg().cloneToModel(model);
159        arg = argCastsInteger()
160                ? model.castExpr("int", model.castExpr("Integer", arg))
161                : arg;
162        StaticIdentifierExpr viewDataBinding =
163                model.staticIdentifier(ModelAnalyzer.VIEW_DATA_BINDING);
164        viewDataBinding.setUserDefinedType(ModelAnalyzer.VIEW_DATA_BINDING);
165        ModelClass targetType = getTarget().getResolvedType();
166        if ((targetType.isList() || targetType.isMap()) &&
167                value.getResolvedType().isPrimitive()) {
168            ModelClass boxed = value.getResolvedType().box();
169            value = model.castExpr(boxed.toJavaCode(), value);
170        }
171        List<Expr> args = Lists.newArrayList(getTarget().cloneToModel(model), arg, value);
172        MethodCallExpr setter = model.methodCall(viewDataBinding, "setTo", args);
173        setter.setAllowProtected();
174        return setter;
175    }
176
177    @Override
178    public Expr cloneToModel(ExprModel model) {
179        return model.bracketExpr(getTarget().cloneToModel(model), getArg().cloneToModel(model));
180    }
181
182    @Override
183    public String toString() {
184        return getTarget().toString() + '[' + getArg() + ']';
185    }
186}
187