#!/usr/bin/env python3
# Copyright: Ankitects Pty Ltd and contributors
# License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
import re

from anki import backend_pb2 as pb
import stringcase

TYPE_DOUBLE = 1
TYPE_FLOAT = 2
TYPE_INT64 = 3
TYPE_UINT64 = 4
TYPE_INT32 = 5
TYPE_FIXED64 = 6
TYPE_FIXED32 = 7
TYPE_BOOL = 8
TYPE_STRING = 9
TYPE_GROUP = 10
TYPE_MESSAGE = 11
TYPE_BYTES = 12
TYPE_UINT32 = 13
TYPE_ENUM = 14
TYPE_SFIXED32 = 15
TYPE_SFIXED64 = 16
TYPE_SINT32 = 17
TYPE_SINT64 = 18

LABEL_OPTIONAL = 1
LABEL_REQUIRED = 2
LABEL_REPEATED = 3


def python_type(field):
    type = python_type_inner(field)
    if field.label == LABEL_REPEATED:
        type = f"List[{type}]"
    return type


def python_type_inner(field):
    type = field.type
    if type == TYPE_BOOL:
        return "bool"
    elif type in (1, 2):
        return "float"
    elif type in (3, 4, 5, 6, 7, 13, 15, 16, 17, 18):
        return "int"
    elif type == TYPE_STRING:
        return "str"
    elif type == TYPE_BYTES:
        return "bytes"
    elif type == 11:
        return "pb." + field.message_type.name
    else:
        raise Exception(f"unknown type: {type}")


def get_input_args(msg):
    fields = sorted(msg.fields, key=lambda x: x.number)
    return ", ".join(["self"] + [f"{f.name}: {python_type(f)}" for f in fields])


def get_input_assign(msg):
    fields = sorted(msg.fields, key=lambda x: x.number)
    return ", ".join(f"{f.name}={f.name}" for f in fields)


def render_method(method, idx):
    input_args = get_input_args(method.input_type)
    input_assign = get_input_assign(method.input_type)
    name = stringcase.snakecase(method.name)
    if len(method.output_type.fields) == 1:
        # unwrap single return arg
        f = method.output_type.fields[0]
        single_field = f".{f.name}"
        return_type = python_type(f)
    else:
        single_field = ""
        return_type = f"pb.{method.output_type.name}"
    return f"""\
    def {name}({input_args}) -> {return_type}:
        input = pb.{method.input_type.name}({input_assign})
        output = pb.{method.output_type.name}()
        output.ParseFromString(self._run_command2({idx+1}, input))
        return output{single_field}
"""


out = []
for idx, method in enumerate(pb._BACKENDSERVICE.methods):
    out.append(render_method(method, idx))

out = "\n".join(out)

path = "anki/rsbackend.py"

with open(path) as file:
    orig = file.read()

new = re.sub(
    "(?s)# @@AUTOGEN@@.*?# @@AUTOGEN@@\n",
    f"# @@AUTOGEN@@\n\n{out}\n    # @@AUTOGEN@@\n",
    orig,
)

with open(path, "wb") as file:
    file.write(new.encode("utf8"))