namespace STCompiler.Compiler;

using System.Collections.Generic;
using STCompiler.Common;

public abstract class StNode {}
public class ProgramNode:StNode{ public List<VarDecl> Vars=new(); public List<Stmt> Stmts=new(); }
public class VarDecl:StNode{ 
    required public string Name; 
    public VarType Type; 
    public Expr? Init; 
}

public abstract class Stmt:StNode{}
public class AssignStmt:Stmt{ 
    required public string Target;   // Variable name
    public Expr? Index;             // Array index if this is an array assignment
    required public Expr Expr;      // Value to assign
}
public class IfStmt:Stmt{ 
    required public Expr Cond; 
    public List<Stmt> ThenStmts=new(); 
    public List<Stmt> ElseStmts=new(); 
}
public class WhileStmt:Stmt{ 
    required public Expr Cond; 
    public List<Stmt> Body=new(); 
}
public class ForStmt:Stmt{ 
    required public string Var; 
    required public Expr Start; 
    required public Expr End; 
    public Expr Step = new IntExpr(1); 
    public List<Stmt> Body=new(); 
}

public abstract class Expr:StNode {
    public VarType Type; // Speichert den Typ des Ausdrucks
}
public class IntExpr:Expr { 
    public long Value; 
    public IntExpr(long v, VarType type = VarType.DINT) {
        Value = v;
        Type = type;
    } 
}
public class RealExpr:Expr { 
    public double Value; 
    public RealExpr(double v, VarType type = VarType.REAL) {
        Value = v;
        Type = type;
    } 
}
public class VarExpr:Expr { 
    public string Name; 
    public VarExpr(string n, VarType type) {
        Name = n;
        Type = type;
    } 
}
public class BinaryExpr:Expr { 
    public Expr L; 
    public Expr R; 
    public TokType Op; 
    public BinaryExpr(Expr l, TokType op, Expr r) {
        L = l;
        Op = op;
        R = r;
        Type = DetermineResultType(l.Type, r.Type);
    }
    
    private static VarType DetermineResultType(VarType left, VarType right) {
        // Wenn einer der Operanden LREAL ist, ist das Ergebnis LREAL
        if (left == VarType.LREAL || right == VarType.LREAL)
            return VarType.LREAL;
        // Wenn einer der Operanden REAL ist, ist das Ergebnis REAL
        if (left == VarType.REAL || right == VarType.REAL)
            return VarType.REAL;
        // Bei gemischten Integer-Typen nehmen wir den größeren
        if ((int)left > (int)right)
            return left;
        return right;
    }
}
public class ArrayAccessExpr : Expr {
    public string ArrayName;
    public Expr Index;
    
    public ArrayAccessExpr(string name, Expr idx, VarType elementType) {
        ArrayName = name;
        Index = idx;
        Type = elementType;
    }
}