sizes = ["64", "32", "16", "8"]
types =      ["S64", "U64", "F64"]
print_sign = ["%lld", "%llu", "%f"]
operations = [
  ["+", "ADD"], ["-", "SUB"], ["/", "DIV"], ["*", "MUL"], ["%", "MOD"],
  [">>", "SHR"], ["<<", "SHL"], ["&", "BITAND"], ["|", "BITOR"], ["^", "BITXOR"],
  ["~", "BITNOT"], ["==", "EQ"], ["!=", "NEQ"], [">", "GT"], ["<", "LT"], ["||", "OR"],
  [">=", "GTE"], ["<=", "LTE"]
]

def should_skip(T, op):
  if T == "F64":
    if op != "DIV" and op != "SUB" and op != "ADD" and op != "MUL" and op != "EQ" and op != "NEQ"\
    and op != "GT" and op != "LT" and op != "GTE" and op != "LTE":
      return True

def update_file(filename, comment_name, data_to_write):
  begin = f"""//
// *Begin* of {comment_name} generated using code_generating_script.py
//
"""
  end = f"""
//
// *End* of {comment_name} generated using code_generating_script.py
//"""

  with open(filename, 'r+') as file:
    data = file.read()
    file.seek(0)

    begin_index = data.find(begin)
    end_index = data.find(end)
    if begin_index == -1 or end_index == -1:
      print(f"Error: Couldn't find comment: {comment_name}")
      exit(0)

    end_index += len(end)

    with open('backup', 'a') as backup:
      backup.write(f"\n*** FILE = {filename} NAME = {comment_name} ***")
      backup.write(f"\n*** FILE = {filename} NAME = {comment_name} ***")
      backup.write(f"\n*** FILE = {filename} NAME = {comment_name} ***")
      backup.write(data)

    a_part = data[0:begin_index]
    b_part = data[begin_index:end_index]
    c_part = data[end_index:len(data)]

    data_to_write = begin + data_to_write + end

    file.write(a_part + data_to_write + c_part)
    file.truncate()



if True:
  result = ""
  enum_members = []
  enum_members.append("BC_END_OF_INSTRUCTIONS")
  enum_members.append("BC_POP_STACK")
  enum_members.append("BC_PUSH_STACK")
  enum_members.append("BC_LOAD_CONSTANT")
  enum_members.append("BC_STORE_CONSTANT")
  enum_members.append("BC_CALL")

  load_store = ["LOAD_FROM_MEMORY", "STORE_TO_MEMORY"]
  for op in load_store:
    for size in sizes:
      enum_members.append(f"BC_{op}{size}")

  for T in types:
    for _, op in operations:
      if should_skip(T, op):
        continue
      enum_members.append(f"BC_{op}_{T}")

  result += "enum Operation: U16{\n"
  for i in enum_members:
    result += f"  {i},\n"
  result += "};\n"

  result += "const char *op_name[] = {\n"
  for i in enum_members:
    result += f"  \"{i}\",\n"
  result += "};\n"
  update_file("bytecode_interpreter.cpp", "enum", result)

#
# Generate switch cases
#
if True:
  result = ""

  for size in sizes:
    result += f"""
    case BC_LOAD_FROM_MEMORY{size}:{{
      U{size} *load_address = b->registers[instr->index_a].pointer{size};
      b->registers[instr->index_c].u{size} = *load_address;
      bc_log("load_address[r%u, %llx] dst[r%u] [0x%llx|%lld|%f]", instr->index_a, load_address, instr->index_c, b->registers[instr->index_c].u{size}, b->registers[instr->index_c].u{size}, b->registers[instr->index_c].u{size});
    }}break;

    case BC_STORE_TO_MEMORY{size}:{{
      U{size} *store_address = b->registers[instr->index_c].pointer{size};
      *store_address = b->registers[instr->index_a].u{size};
      bc_log("src[r%u] store_address[r%u, %llx] value_written[0x%llx|%lld|%f]", instr->index_a, instr->index_c, store_address, *store_address, *store_address, *store_address);
    }}break;
    """

  for sign, T in zip(print_sign, types):
    t = T.lower()

    # Generate arithmetic
    for symbol, op_name in operations:
      if should_skip(T, op_name):
        continue

      ###################################
      # Unary operator special case
      if symbol == "~":
        result += f"""
      case BC_{op_name}_{T}:{{
        {T} left = ({T})b->registers[instr->index_a].{t};
        {T} result = {symbol}left;
        {T} *dst = b->registers[instr->index_c].pointer_{t};
        *dst = result;
        bc_log("{symbol} [{sign}] = [{sign}]", left, result);
      }}break;
      """
        continue
        ################################

      ################################
      # Binary operation
      result += f"""
      case BC_{op_name}_{T}:{{
        {T} left                     = b->registers[instr->index_a].{t};
        {T} right                    = b->registers[instr->index_b].{t};
        {T} result                   = left {symbol} right;
        b->registers[instr->index_c].{t} = result;
        bc_log("[r%s, {sign}] {symbol} [r%s, {sign}] = [r%s, {sign}]", instr->index_a, left, instr->index_b, right, instr->index_c, result);
      }}break;
      """
      ################################
  update_file("bytecode_interpreter.cpp", "switch_cases", result)




# #
# # Copy backup to **WINDOWS** clipboard
# #
# import subprocess
# subprocess.run("clip", universal_newlines=True, input=data)