from .CFG_Node import *


class CFG:
    def __init__(self, in_node: CFG_Node, out_node: CFG_Node):
        self.in_node = in_node
        self.out_node = out_node

    def to_dot(self) -> str:
        visited = set()
        lines = ["digraph CFG {"]

        # optionale Defaults
        lines.append('  node [fontname="Helvetica"];')

        def node_label(node: CFG_Node) -> str:
            # Basislabel aus dem Knoten
            base = node.dot_label() if hasattr(node, "dot_label") else ""

            # semantisches Label aus AST
            if node.ast_node is not None:
                semantic = str(node.ast_node)
                return f"{base}\\n{semantic}" if base else semantic

            return base

        def node_shape(node: CFG_Node) -> str:
            return node.dot_shape() if hasattr(node, "dot_shape") else "box"

        def visit(node: CFG_Node):
            if node.id in visited:
                return
            visited.add(node.id)

            label = node_label(node)
            shape = node_shape(node)

            lines.append(
                f'  n{node.id} [label="{label}", shape={shape}];'
            )

            for child in sorted(node.children, key=lambda n: n.id):
                lines.append(f"  n{node.id} -> n{child.id};")
                visit(child)

        visit(self.in_node)
        lines.append("}")
        return "\n".join(lines)