#!/usr/bin/env python3
import os
import re
import subprocess

class CargoModifier:

    def __init__(self):
        self.depends = list()

    # noinspection PyShadowingNames
    def modify_file(self, path):
        temp = path + '.___'
        try:
            with open(path, 'r') as reader:
                with open(temp, 'w') as writer:
                    self.modify_stream(reader, writer)
            os.remove(path)
            os.rename(temp, path)
        except BaseException as error:
            try:
                os.remove(temp)
            except OSError:
                pass
            raise error

    # chrono = "0.4.38"
    # clap = { version = "4.5.4", features = ["cargo"] }

    def modify_stream(self, reader, writer):
        target = None
        for line in reader:
            if re.search(r'^\[dependencies]$', line):
                print(line, end='', file=writer)
                target = ''
            elif match := re.search(r'^\[target\."(.+)"\.dependencies]$', line):
                print(line, end='', file=writer)
                target, = match.groups()
            elif target is not None:
                if match := re.search(r'^([\w-]+) = "\d+\.\d+\.\d+"$', line):
                    library, = match.groups()
                    self.depends.append((library, target, None))
                elif match := re.search(r'^([\w-]+) = { version = "\d+\.\d+\.\d+", features = \["(\w+)"] }$', line):
                    library, features = match.groups()
                    self.depends.append((library, target, features))
                elif re.search(r'^$', line):
                    print(line, end='', file=writer)
                    target = None
                else:
                    raise RuntimeError(f'Unexpected line: {line.rstrip()}')
            else:
                print(line, end='', file=writer)

    def run_cargo(self):
        for library, target, features in self.depends:
            command = ['cargo', 'add', library]
            if target:
                command.extend(['--target', target])
            if features:
                command.extend(['--features', features])
            self.run_process(*command)

    @classmethod
    def run_process(cls, *args):
        process = subprocess.run(args)
        return process.returncode == 0

def run_main():
    modifier = CargoModifier()
    modifier.modify_file('Cargo.toml')
    modifier.run_cargo()

try:
    run_main()
except (OSError, RuntimeError) as error:
    print(error)
except KeyboardInterrupt:
    pass