import sys
import os
import io
import argparse
from itertools import chain

def key_value_pair(line):
    key, value = line.split("=", 1)
    try:
        value = int(value)
    except:
        pass
    return key, value


def get_indent(str):
    # get indent length
    index = 0
    for i in str:
        if i == " ":
            index += 1
        else:
            break
    return index

def print_line(line):
    global python_indent
    global generate_code_indent
    if line.strip()[0] == "}" or line.strip()[0] == ")":
       python_indent = -1
    split_str = line.split("@")
    if line.strip()[0] != "@" and len(split_str) == 1:
        if get_indent(line) != python_indent and python_indent != -1:
            pass
        else:
            result = ["print(", line, ", file=OUT_STREAM)"]
            python_indent = -1
            if "{" in line or "asm volatile(" in line:
                generate_code_indent = get_indent(line)
            if line.strip().startswith("}") and "{" not in line:
                generate_code_indent -= 4
            if (len(line) == 1 and line[0] == "}"):
                # modify next fun generate_code_indent
                generate_code_indent = -4
            return "\"".join(result)

    if line.strip()[0] == '@':
        # get python indent and first generate_code_indent
        if python_indent == -1:
            generate_code_indent = get_indent(line) - 4
            python_indent = get_indent(line)
        result = split_str[0][python_indent:] + split_str[1]
        return result
    else:
        index = get_indent(split_str[0])
        result = [split_str[0][python_indent:index] + "print("]
        Prefix = " " * (generate_code_indent + 4) + split_str[0].lstrip()
        Suffix = " %("
        for str in split_str[1:]:
            second = str.find("}")
            Suffix += str[1:second] + ', '
            str = str.replace(str[0:second + 1], "%d")
            Prefix += str
        result.append(Prefix)
        result.append(Suffix + "), file=OUT_STREAM)")
        return "\"".join(result)

def generate_code(template_file, exec_globals):
    if sys.version_info > (3, 0):
        output_stream = io.StringIO()
    else:
        output_stream = io.BytesIO()
    with open(template_file, 'r') as f:
        generate_code_lines = []
        for line in f:
            line = line.replace("\n", "")
            if len(line.strip()) != 0 and line.strip()[0] != "@":
                line = line.replace("\"", "\\\"")
            line = line.replace("%", "%%")
            if "print" in line:
                line = line.replace("%%", "%")
            if not len(line):
                generate_code_lines.append("print(" + "\"" + line + "\"" + ", file=OUT_STREAM)")
            else:
                str = print_line(line)
                if "%(" not in str:
                    str = str.replace("%%[", "%[")
                generate_code_lines.append(str)
        # print('\n'.join(generate_code_lines))
        c = compile('\n'.join(generate_code_lines), '', 'exec')
        exec_globals["OUT_STREAM"] = output_stream
        exec(c, exec_globals)
    return output_stream.getvalue()

generate_code_indent = -4
python_indent = -1

parser = argparse.ArgumentParser(description="MSLite NNACL Code Generator")
parser.add_argument("-I", dest="Template_File", nargs=1, help="template file to generate code")
parser.add_argument("-A", dest="defines", metavar="KEY=VALUE", nargs="*", type=key_value_pair, action="append", help="Custom Parameters")
parser.add_argument("-O", dest="Output_File", nargs=1, help="generate code output file path")

if __name__ == "__main__":
  parameters = parser.parse_args(sys.argv[1:])
  exec_globals = dict(chain(*parameters.defines))

  generate_code_str = generate_code(parameters.Template_File[0], exec_globals)
  if os.path.exists(parameters.Output_File[0]):
      os.remove(parameters.Output_File[0])

  saveDir = os.path.dirname(parameters.Output_File[0])
  if not os.path.exists(saveDir):
      print(saveDir)
      os.mkdir(saveDir)
  with open(parameters.Output_File[0], "w", encoding='utf-8') as output_file:
      output_file.write(generate_code_str)