#! /usr/bin/python3

import os
import sys
import getopt

from fx92.parser import Parser
from fx92.lexer import UrlLexer, TextLexer
from fx92.printer import print_ast
from fx92.drawing import Window, InterruptException
from fx92.interpreter import Context
from fx92.keyseq import print_key_sequence

#---
# Main program
#---

usage_string = """
usage: {} [-s|-u] <file> [options...]

If "-" is specified as input, stdin is read.

Input mode (default is -s):
  -s  Input file is an ASCII script ("GOTO 12, 35")
  -u  Input file is a wes.casio.com URL ("https://...F908313200333500")

Output options:
  --quiet         Do not show the SDL window
  --save=<file>   Save a copy of the screen output in a bitmap file
  --scale=<n>     Window scale up (default 4, max 16)
  --stream=<dir>  Capture rendering in real time, outputs a series of bitmaps
  --keyseq        Output key sequence for Aditya02's hardware mod
""".format(sys.argv[0]).strip()

def usage(exitcode=None):
    print(usage_string, file=sys.stderr)

    if exitcode is not None:
        sys.exit(exitcode)

def main():
    # Read command-line arguments
    try:
        opts, args = getopt.gnu_getopt(sys.argv[1:], "hus",
            ["help", "quiet", "keyseq", "save=", "scale=", "debug=", "stream="])
        opts = dict(opts)

        if len(sys.argv) == 1 or "-h" in opts or "--help" in opts:
            usage(0)

        if "-u" in opts and "-s" in opts:
            raise getopt.GetoptError("-s (script input) and -u (URL input) "
                "are exclusive")

        if len(args) < 1:
            usage(1)
        if len(args) > 1:
            raise getopt.GetoptError("only one input file can be specified")

    except getopt.GetoptError as e:
        print("error:", e, file=sys.stderr)
        print("Try '{} --help' for details.".format(sys.argv[0]), file=sys.stderr)
        sys.exit(1)

    # Other parameters
    quiet = "--quiet" in opts
    out = opts.get("--save", None)
    debug = opts.get("--debug", None)
    stream = opts.get("--stream", False)
    keyseq = opts.get("--keyseq", None)

    scale = int(opts.get("--scale", "4"))
    if scale < 1:
        scale = 1
    if scale > 16:
        scale = 16

    # Read the input program
    file = args[0]
    if file == "-":
        program = sys.stdin.read()
    else:
        with open(file, "r") as fp:
            program = fp.read()

    # URL mode
    if "-u" in opts:
        lexer = UrlLexer(program)
    # Default, script mode
    else:
        lexer = TextLexer(program)

    # Lexer debug mode, just print the token stream
    if debug == "lexer":
        lexer.dump()
        return 0

    parser = Parser(lexer)
    ast = parser.parse_program()
    ast = ast.simplify()

    # Parser debug mode, print the AST
    if debug == "parser":
        print_ast(ast, lang="ast")
        return 0

    # Key sequence mode, print a key sequence
    if keyseq is not None:
        print_key_sequence(ast)
        return 0

    # Create the folder for streaming capture
    if stream:
        try:
            os.mkdir(stream)
        except FileExistsError:
            print("error: folder {} already exists, avoiding overwrite".format(
                stream))
            return 1

    with Window(width=192, height=47, scale=scale, quiet=quiet,
        stream=stream) as w:
        ctx = Context(w)
        try:
            ctx.run(ast)
            if out is not None:
                w.save(out)
            w.wait()
        except InterruptException:
            print("[interpreter] Interrupted.", file=sys.stderr)

    return 0

if __name__ == "__main__":
    sys.exit(main())