9 files changed, 378 insertions, 0 deletions
diff --git a/main/core/parser/Parser.java b/main/core/parser/Parser.java
new file mode 100644
index 0000000..af62f7e
--- /dev/null
+++ b/main/core/parser/Parser.java
@@ -0,0 +1,171 @@
+package com.jantuomi.interpreter.main.core.parser;
+
+import com.jantuomi.interpreter.main.core.parser.ast.*;
+import com.jantuomi.interpreter.main.core.tokenizer.token.Token;
+import com.jantuomi.interpreter.main.utils.Counter;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * Created by jan on 11.6.2016.
+ */
+public class Parser {
+    private static final Parser instance = new Parser();
+
+    private List<Token> tokens;
+    private List<ASTNode> statementSequence;
+
+    public static Parser getInstance() {
+        return instance;
+    }
+
+    private Parser() {
+
+    }
+
+    public List<ASTNode> parse(List<Token> tokens) {
+        this.tokens = tokens;
+        this.statementSequence = new ArrayList<>();
+
+        Counter c = new Counter();
+        while (c.getValue() < tokens.size()) {
+            AssignmentNode asn = expectAssignmentRoutine(c);
+            if (asn != null) {
+                statementSequence.add(asn);
+                continue;
+            }
+            AdditionNode adn = expectAdditionRoutine(c);
+            if (adn != null) {
+                statementSequence.add(adn);
+                continue;
+            }
+        }
+
+        return statementSequence;
+    }
+
+    public AssignmentNode expectAssignmentRoutine(Counter c) {
+        Counter d = c.clone();
+
+        SymbolNode lhs = expectLHS(d);
+        if (lhs == null) {
+            return null;
+        }
+        boolean isAssign = expectAssignmentAndAdvance(d);
+        if (!isAssign) {
+            return null;
+        }
+        ExpressionNode rhs = expectRHS(d);
+        if (rhs == null) {
+            return null;
+        }
+
+        AssignmentNode an = new AssignmentNode(lhs, rhs);
+        c.setValue(d.getValue());
+        return an;
+    }
+
+    public SymbolNode expectLHS(Counter c) {
+        SymbolNode sn = parseSymbolAndAdvance(c);
+        if (sn != null) {
+            return sn;
+        }
+        return null;
+    }
+
+    public ExpressionNode expectRHS(Counter c) {
+        ExpressionNode en = expectExpression(c);
+        if (en != null) {
+            return en;
+        }
+        return null;
+    }
+
+    private ExpressionNode expectExpression(Counter c) {
+        Counter d = c.clone();
+
+        AdditionNode an = expectAdditionRoutine(d);
+        if (an != null) {
+            c.setValue(d.getValue());
+            return an;
+        }
+        IntegerLiteralNode in = parseIntegerLiteralAndAdvance(d);
+        if (in != null) {
+            c.setValue(d.getValue());
+            return in;
+        }
+        SymbolNode sn = parseSymbolAndAdvance(d);
+        if (sn != null) {
+            c.setValue(d.getValue());
+            return sn;
+        }
+
+        return null;
+    }
+
+    private AdditionNode expectAdditionRoutine(Counter c) {
+        Counter d = c.clone();
+
+        ExpressionNode lhs = expectLHS(d);
+        if (lhs == null) {
+            return null;
+        }
+        boolean isAddition = expectAdditionAndAdvance(d);
+        if (!isAddition) {
+            return null;
+        }
+        ExpressionNode rhs = expectRHS(d);
+        if (rhs == null) {
+            return null;
+        }
+
+        AdditionNode an = new AdditionNode(lhs, rhs);
+        c.setValue(d.getValue());
+        return an;
+    }
+
+    private boolean expectAdditionAndAdvance(Counter c) {
+        if (tokens.get(c.getValue()).is(Token.Type.AdditionToken)) {
+            c.advance();
+            return true;
+        } else {
+            return false;
+        }
+    }
+
+    private IntegerLiteralNode parseIntegerLiteralAndAdvance(Counter c) {
+        if (tokens.get(c.getValue()).is(Token.Type.IntegerLiteralToken)) {
+            IntegerLiteralNode in = new IntegerLiteralNode(tokens.get(c.getValue()));
+            c.advance();
+            return in;
+        } else {
+            return null;
+        }
+    }
+
+    public boolean expectAssignmentAndAdvance(Counter c) {
+        if (tokens.get(c.getValue()).is(Token.Type.AssignmentToken)) {
+            c.advance();
+            return true;
+        } else {
+            return false;
+        }
+    }
+
+    public SymbolNode parseSymbolAndAdvance(Counter c) {
+        if (tokens.get(c.getValue()).is(Token.Type.SymbolToken)) {
+            SymbolNode sn = new SymbolNode(tokens.get(c.getValue()));
+            c.advance();
+            return sn;
+        } else {
+            return null;
+        }
+    }
+
+    public void printTree(ASTNode e) {
+        System.out.println("### Tree begin ###");
+        e.print(0);
+        System.out.println("### Tree end ###");
+    }
+}
diff --git a/main/core/parser/ast/ASTNode.java b/main/core/parser/ast/ASTNode.java
new file mode 100644
index 0000000..106ff75
--- /dev/null
+++ b/main/core/parser/ast/ASTNode.java
@@ -0,0 +1,33 @@
+package com.jantuomi.interpreter.main.core.parser.ast;
+
+import com.jantuomi.interpreter.main.core.parser.datatype.DataContainer;
+import com.jantuomi.interpreter.main.core.tokenizer.token.Token;
+
+import java.util.List;
+
+/**
+ * Created by jan on 11.6.2016.
+ */
+abstract public class ASTNode {
+
+    public abstract DataContainer evaluate();
+
+    protected Token source;
+
+    public ASTNode(Token token) {
+        this.source = token;
+    }
+
+    abstract List<ASTNode> getChildren();
+
+    public void print(int indent) {
+        for (int i = 0; i < indent; i++) {
+            System.out.print("\t");
+        }
+
+        System.out.println(source.toString());
+        for (ASTNode node : getChildren()) {
+            node.print(indent + 1);
+        }
+    }
+}
diff --git a/main/core/parser/ast/AdditionNode.java b/main/core/parser/ast/AdditionNode.java
new file mode 100644
index 0000000..3117e41
--- /dev/null
+++ b/main/core/parser/ast/AdditionNode.java
@@ -0,0 +1,34 @@
+package com.jantuomi.interpreter.main.core.parser.ast;
+
+import com.jantuomi.interpreter.main.core.parser.datatype.DataContainer;
+import com.jantuomi.interpreter.main.core.tokenizer.token.Token;
+
+import java.util.Arrays;
+import java.util.List;
+
+
+/**
+ * Created by jan on 13.6.2016.
+ */
+public class AdditionNode extends ExpressionNode {
+
+    private ExpressionNode lhs;
+    private ExpressionNode rhs;
+
+    public AdditionNode(ExpressionNode lhs, ExpressionNode rhs) {
+        super(new Token(Token.Type.AdditionToken));
+
+        this.lhs = lhs;
+        this.rhs = rhs;
+    }
+
+    @Override
+    public List<ASTNode> getChildren() {
+        return Arrays.asList(lhs, rhs);
+    }
+
+    @Override
+    public DataContainer evaluate() {
+        return null;
+    }
+}
diff --git a/main/core/parser/ast/AssignmentNode.java b/main/core/parser/ast/AssignmentNode.java
new file mode 100644
index 0000000..8d8f8bc
--- /dev/null
+++ b/main/core/parser/ast/AssignmentNode.java
@@ -0,0 +1,36 @@
+package com.jantuomi.interpreter.main.core.parser.ast;
+
+import com.jantuomi.interpreter.main.core.parser.datatype.DataContainer;
+import com.jantuomi.interpreter.main.core.runtime.State;
+import com.jantuomi.interpreter.main.core.tokenizer.token.Token;
+
+import java.util.Arrays;
+import java.util.List;
+
+/**
+ * Created by jan on 11.6.2016.
+ */
+public class AssignmentNode extends ASTNode {
+
+    private SymbolNode lhs;
+    private ExpressionNode rhs;
+
+    public AssignmentNode(SymbolNode lhs, ExpressionNode rhs) {
+        super(new Token(Token.Type.AssignmentToken));
+
+        this.lhs = lhs;
+        this.rhs = rhs;
+    }
+
+    @Override
+    public DataContainer evaluate() {
+        DataContainer value = rhs.evaluate();
+        State.getInstance().setSymbolValue(lhs.getSymbol(), value);
+        return value;
+    }
+
+    @Override
+    List<ASTNode> getChildren() {
+        return Arrays.asList(lhs, rhs);
+    }
+}
diff --git a/main/core/parser/ast/ExpressionNode.java b/main/core/parser/ast/ExpressionNode.java
new file mode 100644
index 0000000..ac1a190
--- /dev/null
+++ b/main/core/parser/ast/ExpressionNode.java
@@ -0,0 +1,12 @@
+package com.jantuomi.interpreter.main.core.parser.ast;
+
+import com.jantuomi.interpreter.main.core.tokenizer.token.Token;
+
+/**
+ * Created by jan on 11.6.2016.
+ */
+abstract public class ExpressionNode extends ASTNode {
+    public ExpressionNode(Token token) {
+        super(token);
+    }
+}
diff --git a/main/core/parser/ast/IntegerLiteralNode.java b/main/core/parser/ast/IntegerLiteralNode.java
new file mode 100644
index 0000000..b68adf0
--- /dev/null
+++ b/main/core/parser/ast/IntegerLiteralNode.java
@@ -0,0 +1,30 @@
+package com.jantuomi.interpreter.main.core.parser.ast;
+
+import com.jantuomi.interpreter.main.core.parser.datatype.DataContainer;
+import com.jantuomi.interpreter.main.core.tokenizer.token.Token;
+
+import java.util.Arrays;
+import java.util.List;
+
+/**
+ * Created by jan on 13.6.2016.
+ */
+public class IntegerLiteralNode extends ExpressionNode {
+
+    private int data;
+
+    public IntegerLiteralNode(Token token) {
+        super(token);
+        this.data = Integer.parseInt(token.getText());
+    }
+
+    @Override
+    List<ASTNode> getChildren() {
+        return Arrays.asList();
+    }
+
+    @Override
+    public DataContainer evaluate() {
+        return null;
+    }
+}
diff --git a/main/core/parser/ast/SymbolNode.java b/main/core/parser/ast/SymbolNode.java
new file mode 100644
index 0000000..1457851
--- /dev/null
+++ b/main/core/parser/ast/SymbolNode.java
@@ -0,0 +1,35 @@
+package com.jantuomi.interpreter.main.core.parser.ast;
+
+import com.jantuomi.interpreter.main.core.parser.datatype.DataContainer;
+import com.jantuomi.interpreter.main.core.runtime.State;
+import com.jantuomi.interpreter.main.core.tokenizer.token.Token;
+
+import java.util.Arrays;
+import java.util.List;
+
+/**
+ * Created by jan on 11.6.2016.
+ */
+public class SymbolNode extends ExpressionNode {
+    private String symbol;
+
+    public SymbolNode(Token token) {
+        super(token);
+
+        this.symbol = token.getText();
+    }
+
+    @Override
+    List<ASTNode> getChildren() {
+        return Arrays.asList();
+    }
+
+    public String getSymbol() {
+        return symbol;
+    }
+
+    @Override
+    public DataContainer evaluate() {
+        return State.getInstance().getSymbolValue(symbol);
+    }
+}
diff --git a/main/core/parser/datatype/DataContainer.java b/main/core/parser/datatype/DataContainer.java
new file mode 100644
index 0000000..48e72a3
--- /dev/null
+++ b/main/core/parser/datatype/DataContainer.java
@@ -0,0 +1,17 @@
+package com.jantuomi.interpreter.main.core.parser.datatype;
+
+
+/**
+ * Created by jan on 11.6.2016.
+ */
+abstract public class DataContainer<T> {
+    public T getData() {
+        return data;
+    }
+
+    public void setData(T data) {
+        this.data = data;
+    }
+
+    private T data;
+}
diff --git a/main/core/parser/datatype/IntegerDataContainer.java b/main/core/parser/datatype/IntegerDataContainer.java
new file mode 100644
index 0000000..c5b9fb0
--- /dev/null
+++ b/main/core/parser/datatype/IntegerDataContainer.java
@@ -0,0 +1,10 @@
+package com.jantuomi.interpreter.main.core.parser.datatype;
+
+/**
+ * Created by jan on 11.6.2016.
+ */
+public class IntegerDataContainer extends DataContainer<Integer> {
+    public IntegerDataContainer(Integer data) {
+        this.setData(data);
+    }
+}