package fr.celticinfo.lox

/**
 * The ExprVisitor interface is used to visit the different types of expressions that can be parsed by the Parser.
 */
interface ExprVisitor<R> {
    fun visitAssign(expr: Assign): R
    fun visitBinary(expr: Binary): R
    fun visitCall(expr: Call): R
    fun visitGet(expr: Get): R
    fun visitGrouping(expr: Grouping): R
    fun visitLiteral(expr: Literal): R
    fun visitLogical(expr: Logical): R
    fun visitSet(expr: Set): R
    fun visitSuper(expr: Super): R
    fun visitThis(expr: This): R
    fun visitUnary(expr: Unary): R
    fun visitVariable(expr: Variable): R
}

/**
 * The Expr class represents the different types of expressions that can be parsed by the Parser.
 */
sealed class Expr {
    abstract fun <R> accept(visitor: ExprVisitor<R>): R
}

data class Assign(
    val name: Token,
    val value: Expr
) : Expr() {
    override fun <R> accept(visitor: ExprVisitor<R>): R {
        return visitor.visitAssign(this)
    }
}

data class Binary(
    val left: Expr, val operator: Token, val right: Expr
) : Expr() {
    override fun <R> accept(visitor: ExprVisitor<R>): R {
        return visitor.visitBinary(this)
    }
}

data class Call(
    val callee: Expr,
    val paren: Token,
    val arguments: List<Expr>
) : Expr() {
    override fun <R> accept(visitor: ExprVisitor<R>): R {
        return visitor.visitCall(this)
    }
}

data class Get(
    val obj: Expr,
    val name: Token
) : Expr() {
    override fun <R> accept(visitor: ExprVisitor<R>): R {
        return visitor.visitGet(this)
    }
}

data class Grouping(
    val expression: Expr
) : Expr() {
    override fun <R> accept(visitor: ExprVisitor<R>): R {
        return visitor.visitGrouping(this)
    }
}

data class Literal(
    val value: Any?
) : Expr() {
    override fun <R> accept(visitor: ExprVisitor<R>): R {
        return visitor.visitLiteral(this)
    }
}

data class Logical(
    val left: Expr,
    val operator: Token,
    val right: Expr
) : Expr() {
    override fun <R> accept(visitor: ExprVisitor<R>): R {
        return visitor.visitLogical(this)
    }
}

data class Set(
    val obj: Expr,
    val name: Token,
    val value: Expr
) : Expr() {
    override fun <R> accept(visitor: ExprVisitor<R>): R {
        return visitor.visitSet(this)
    }
}

data class Super(
    val keyword: Token,
    val method: Token
) : Expr() {
    override fun <R> accept(visitor: ExprVisitor<R>): R {
        return visitor.visitSuper(this)
    }
}

data class This(
    val keyword: Token
) : Expr() {
    override fun <R> accept(visitor: ExprVisitor<R>): R {
        return visitor.visitThis(this)
    }
}

data class Unary(
    val operator: Token, val right: Expr
) : Expr() {
    override fun <R> accept(visitor: ExprVisitor<R>): R {
        return visitor.visitUnary(this)
    }
}

data class Variable(
    val name: Token
) : Expr() {
    override fun <R> accept(visitor: ExprVisitor<R>): R {
        return visitor.visitVariable(this)
    }
}