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


# ------------------------------------------------------------
# Utility: rendering DOT → PNG → matplotlib
# ------------------------------------------------------------

def render_ast(dotfile: str, outfile: str = "ast.png"):
    with open(dotfile) as f:
        dot_data = f.read()

    src = Source(dot_data)
    src.render(outfile.replace(".png", ""), format="png", cleanup=True)

    # Show via matplotlib only
    img = mpimg.imread(outfile)
    plt.imshow(img)
    plt.axis("off")
    plt.show()


# ------------------------------------------------------------
# Pretty print AST
# ------------------------------------------------------------

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

    for key, value in node.__dict__.items():
        if key == "pp":
            continue
        if isinstance(value, list):
            print(f"{prefix}  {key}: [")
            for v in value:
                if isinstance(v, syntax.EXPRESSION):
                    pretty_print(v, indent + 4)
                else:
                    print(" " * (indent + 4) + str(v))
            print(f"{prefix}  ]")
        elif isinstance(value, syntax.EXPRESSION):
            print(f"{prefix}  {key}:")
            pretty_print(value, indent + 4)
        else:
            print(f"{prefix}  {key}: {value}")

# Ask for a choice input
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 and {len(options)}.")

# Ask for a yes/no input
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")

# Ask for a value input
def prompt_value(prompt: str, default: str):
    s = input(f"{prompt} [{default}]: ").strip()
    return s if s else default

# Search for known .tripla files
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 program", "Exit"])

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

        else:
            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_name = prompt_value("\nSave DOT as", "ast.dot")
            if not dot_name.endswith(".dot"):
                dot_name += ".dot"
            ast.to_dot(ast, dot_name)

            # Show graph
            if prompt_yesno("Display AST diagram?"):
                render_ast(dot_name, "ast.png")
                print("Rendered AST to ast.png")

            print("\nDone.")