import triplayacc as yacc
import triplalex as lex
import syntax

from pathlib import Path
from graphviz import Source
import matplotlib.pyplot as plt
import matplotlib.image as mpimg
import os

import matplotlib
matplotlib.use("TkAgg")

def render_ast_from_string(dot_string: str):
    # Set DPI for PNG
    os.environ["GV_FILE_DPI"] = "300"

    src = Source(dot_string, format="png", engine="dot")
    png_path = src.render(cleanup=True)

    img = mpimg.imread(png_path)

    fig = plt.figure(figsize=(12, 12))
    fig.canvas.manager.window.wm_title("TRIPLA AST Viewer")

    plt.imshow(img)
    plt.axis("off")
    plt.show()

def pretty_print(node, indent=0):
    prefix = " " * indent
    print(f"{prefix}{type(node).__name__}:")

    for key, value in node.__dict__.items():
        if isinstance(value, syntax.EXPRESSION):
            pretty_print(value, indent + 4)

        elif isinstance(value, list):
            print(f"{prefix}  {key}: [")
            for element in value:
                if isinstance(element, syntax.EXPRESSION):
                    pretty_print(element, indent + 4)
                else:
                    print(" " * (indent + 4) + str(element))
            print(f"{prefix}  ]")

        else:
            print(f"{prefix}  {key}: {value}")

def export_dot_file(dot_string: str, filename: str):
    try:
        Path(filename).write_text(dot_string, encoding="utf-8")
        print(f"Saved DOT file as: {filename}")
    except Exception as e:
        print(f"Could not save DOT file: {e}")

def __prompt_choice(prompt: str, options: list) -> int:
    print(prompt)
    for i, opt in enumerate(options, 1):
        print(f"  {i}. {opt}")

    while True:
        try:
            s = input(f"Enter choice (1-{len(options)}): ").strip()
            idx = int(s) - 1
            if 0 <= idx < len(options):
                return idx
        except Exception:
            pass
        print(f"Invalid. Enter a number between 1-{len(options)}.")

def __prompt_yesno(question: str, default="y"):
    s = input(f"{question} (y/n) [{default}]: ").strip().lower()
    if not s:
        s = default
    return s.startswith("y")

def __search_programs():
    base = Path(__file__).parent / "triplaprograms"
    if not base.exists():
        return []
    return sorted([f for f in base.glob("*.tripla")])

if __name__ == "__main__":
    print("\nTRIPLA Parser Tool")

    while True:
        choice = __prompt_choice("\nSelect action:", ["Parse .tripla", "Exit"])

        if choice == 1:
            print("\nBye Bye.")
            break

        programs = __search_programs()
        if not programs:
            print("\nNo .tripla files found.")
            continue

        idx = __prompt_choice("\nSelect program to parse:", [p.name for p in programs])
        path = programs[idx]

        source = path.read_text()
        ast = yacc.parser.parse(source)

        # Pretty print
        if __prompt_yesno("\nPretty-print AST?"):
            print("")
            pretty_print(ast)

        # Export DOT
        dot_str = ast.to_dot()
        if __prompt_yesno("Export AST as .dot file?"):
            default = f"{path.stem}.dot"
            out = input(f"Filename [{default}]: ").strip()
            if not out:
                out = default
            export_dot_file(dot_str, out)

        # Display AST diagram
        if __prompt_yesno("Display AST diagram?"):
            render_ast_from_string(dot_str)
            print("Rendered AST diagram.")