AST.py

#  Authors:  Ariana Matcheama, Jessica Douthit, Deanna M. Wilborne
#  College:  Berea College
#  Purpose:  AST Class
#           Copyright (2023) Deanna M. Wilborne

from anytree import NodeMixin, RenderTree
from Common import Common
from sys import platform

if platform != "win32":
    import curses.ascii as ca


# noinspection SpellCheckingInspection
class AST(NodeMixin):
    version = "2024-04-29"

    #     name: is the node name - this is used by anything that processes the AST after created, like an
    #           emitter
    #    value: is a dictionary - this dictionary contains annotations that can be useful for both
    #           compilation and emitting of machine code from an AST
    #               type - data type if applicable
    #   struct: is a dictionary - this dictionary contains annotations that can be useful for structural
    #           aspects of the AST
    #               term - node is a terminal node (False) otherwise True (set by grammar)
    #   parent: optional but can be used to link to the parent node
    # children: represents the children the node is connected to - children go in a list
    #     line: the line number the AST node was created from
    #    index: ?? TODO: figure out purpose (it is likely the starting character in the source file by character #)
    def __init__(self, name: str, value: {} = None, struct: {} = None, parent=None,
                 children: [] = None, line: int = None, index: int = None) -> None:
        self.name = name
        self.parent = parent

        if value is None:
            self.value = {'type': None}
        else:
            self.value = value

        if struct is None:
            self.struct = {'term': False}
        else:
            self.struct = struct

        # 2023-04-16, DWM, line and index is based on:
        # https://my.eng.utah.edu/~cs3100/lectures/l14/ply-3.4/doc/ply.html#ply_nn33
        self.line = line
        self.index = index

        if children is not None:
            self.children = children

    # 2023-04-24, DMW, substitute control characters in value attibutes of type string
    def safe_value(self) -> str:
        output = ""
        for char in self.value:
            output += ca.unctrl(char)
        return output

    # 2023-04-24, DMW, provide ability to print node details
    def __str__(self) -> str:
        output_str = "{" + " name='{}'".format(self.name)
        if self.value is not None:
            if platform != "win32":
                if Common.object_type(self.value) == "str":
                    output_str += ", value='{}'".format(self.safe_value())
                else:
                    output_str += ", value='{}'".format(self.value)
            else:
                output_str += ", value='{}'".format(self.value)
        if self.parent is not None:
            output_str += ", parent='{}'".format(self.parent.name)
        if self.children is not None:
            if len(self.children) != 0:
                children = ""
                for child in self.children:
                    if children != "":
                        children += ", '{}'".format(child.name)
                    else:
                        children = "[ '{}'".format(child.name)
                children += " ]"
                output_str += ", children={}".format(children)
        if self.line is not None:
            output_str += ", line={}".format(self.line)
        if self.index is not None:
            output_str += ", index={}".format(self.index)
        output_str += " }"
        return output_str

    # 2024-02-12, DMW, added class static method
    @staticmethod
    def render_tree(tree) -> None:
        # 2024-04-27, DMW, added the follow error checking
        if tree is None:
            print("AST.render_tree(): There is no tree to render.")
            return

        for pre, fill, node in RenderTree(tree):
            if node is None:
                print("RENDER_TREE: Invalid Node Object")
                continue
            # print("node value={}".format(node.value))
            if node.value is None:
                node_info = node.name
            else:
                node_info = node.name + "(" + str(node.value) + ")"
            pre_text = str(pre).replace("\t", "    ")
            ast_row = "%s%s" % (pre_text, node_info)
            ast_row = ast_row.replace("\t", "    ")
            # print("%s%s" % (pre, node_info))
            print(ast_row)

    # 2024-04-23, DMW, created the following class that allows emitting the
    # AST as a multiline string that can be included in the output from an emitter
    @staticmethod
    def render_tree_str(tree, prefix_str: str = "") -> str:
        output = ""
        for pre, fill, node in RenderTree(tree):
            # print("node value={}".format(node.value))
            if node.value is None:
                node_info = node.name
            else:
                node_info = node.name + "(" + str(node.value) + ")"
            pre_text = str(pre).replace("\t", "    ")
            ast_row = "%s%s" % (pre_text, node_info)
            ast_row = ast_row.replace("\t", "    ")
            # print("%s%s" % (pre, node_info))
            # print(ast_row)
            output += prefix_str + ast_row + "\n"
        return output


# limited functional testing
# 2023-04-24, DMW, updated to use test() to prevent pycharm warnings about shadowing "child"
if __name__ == "__main__":
    def test():
        child2 = AST("child2", value="2")
        child3a = AST("child3a", value="3a")
        child3b = AST("child3b", value="3b")
        child3 = AST("child3", value="3", children=[child3a, child3b])
        child = AST("child", children=[child2, child3])
        root = AST("root", value="\ntest\n", children=[child])
        AST.render_tree(root)

    test()