#/usr/bin/python3

"""
Маленький скрипт для сборки бинарных файликов для потока-симулятора из +- человекочитаемого текста
"""

import argparse
import sys
import struct
import re

time_suffixes = {
        "": 1,
        "ms": 1,
        "s":  1000,
        }
size_suffiexes = {
        "": 1,
        "kb": 2 ** 10,
        "Mb": 2 ** 20,
        "Gb": 2 ** 30
        }

operations = {
        "exit":             0x00,
        "reserve_region":   0x01,
        "pass_block":       0x02,
        "non_save_block":   0x03,
        "free_region":      0x04,
        "return_block":     0x05,
        "lock_block":       0x06,
        "unlock_block":     0x07,
        "mess_region":      0x08
        }

access = {
        "page_noaccess":          0x01,
        "page_readonly":          0x02,
        "r":                      0x02,
        "page_readwrite":         0x04,
        "rw":                     0x04,
        "page_execute":           0x10,
        "e":                      0x10,
        "page_execute_read":      0x20,
        "re":                     0x20,
        "page_execute_readwrite": 0x40,
        "rwe":                    0x40
        }

def main():
    parser = argparse.ArgumentParser(prog="simasm")
    parser.add_argument("--file", "-f", type=str, help="file with program")
    parser.add_argument("--output", "-o", type=str, help="file to store program")
    args = parser.parse_args()

    program = ""
    if args.file:
        with open(args.file, "r", encoding="utf-8") as f:
            program = f.read()
    else:
        program = sys.stdin.read()

    program = re.sub("#.*$", "", program, flags=re.M)
    program = " ".join(program.split())
    lines = list(filter(lambda s: s!="", program.split(";")))
    binary = bytearray()
    for line in lines:
        words = line.split()
        if len(words) != 5:
            print("wrong line")
            sys.exit(1)
        # timestamp
        m = re.match(r"(\d+)(\w*)", words[0])
        assert m
        time_offset = int(m.group(1)) * time_suffixes[m.group(2)]

        region_in = words[1]
        region = 0
        if region_in.startswith("0x"):
            region = int(region_in, 16)
        else:
            region = int(region_in)

        operation = operations[words[2]]
        
        m = re.match(r"(\d+)(\w*)", words[3])
        assert m
        size = int(m.group(1)) * size_suffiexes[m.group(2)]

        pg_access = access[words[4]]

        binary += struct.pack("QQQQQ", time_offset, operation, region, size, pg_access)
        
    if args.output:
        with open(args.output, "wb") as f:
            f.write(binary)
    else:
        print(binary.hex())

if __name__ == "__main__":
    main()