first step to creating dream lib

argenta/app/entity.py

@@ -0,0 +1,145 @@
+from typing import Callable
+from ..router.entity import Router
+from .exceptions import (InvalidRouterInstanceException,
+                         InvalidDescriptionMessagePatternException,
+                         OnlyOneMainRouterIsAllowedException,
+                         MissingMainRouterException,
+                         MissingHandlersForUnknownCommandsOnMainRouterException,
+                         HandlerForUnknownCommandsCanOnlyBeDeclaredForMainRouterException)
+
+
+class App:
+    def __init__(self,
+                 prompt: str = 'Enter a command',
+                 exit_command: str = 'q',
+                 ignore_exit_command_register: bool = True,
+                 initial_greeting: str = 'Hello',
+                 goodbye_message: str = 'GoodBye',
+                 line_separate: str = '\n',
+                 command_group_description_separate: str = '\n',
+                 print_func: Callable[[str], None] = print) -> None:
+        self.prompt = prompt
+        self.print_func = print_func
+        self.exit_command = exit_command
+        self.ignore_exit_command_register = ignore_exit_command_register
+        self.goodbye_message = goodbye_message
+        self.initial_greeting = initial_greeting
+        self.line_separate = line_separate
+        self.command_group_description_separate = command_group_description_separate
+
+        self.routers: list[Router] = []
+        self.registered_commands: list[dict[str, str | list[dict[str, Callable[[], None] | str]] | Router]] = []
+        self.main_app_router: Router | None = None
+        self._description_message_pattern = '[{command}] *=*=* {description}'
+
+
+    def start_polling(self) -> None:
+        self.print_func(self.initial_greeting)
+        self.validate_main_router()
+
+        while True:
+            self.print_command_group_description()
+            self.print_func(self.prompt)
+
+            command: str = input()
+
+            self.checking_command_for_exit_command(command)
+            self.print_func(self.line_separate)
+
+            is_unknown_command: bool = self.check_is_command_unknown(command)
+
+            if is_unknown_command:
+                continue
+
+            for router in self.routers:
+                router.input_command_handler(command)
+            self.print_func(self.line_separate)
+            self.print_func(self.command_group_description_separate)
+
+
+    def set_initial_greeting(self, greeting: str) -> None:
+        self.initial_greeting = greeting
+
+
+    def set_goodbye_message(self, message: str) -> None:
+        self.goodbye_message = message
+
+
+    def set_description_message_pattern(self, pattern: str) -> None:
+        try:
+            pattern.format(command='command',
+                           description='description')
+        except KeyError:
+            raise InvalidDescriptionMessagePatternException(pattern)
+        self._description_message_pattern = pattern
+
+
+    def validate_main_router(self):
+        if not self.main_app_router:
+            raise MissingMainRouterException()
+
+        if not self.main_app_router.unknown_command_func:
+            raise MissingHandlersForUnknownCommandsOnMainRouterException()
+
+        for router in self.routers:
+            if router.unknown_command_func and self.main_app_router is not router:
+                raise HandlerForUnknownCommandsCanOnlyBeDeclaredForMainRouterException()
+
+
+    def checking_command_for_exit_command(self, command: str):
+        if command.lower() == self.exit_command.lower():
+            if self.ignore_exit_command_register:
+                self.print_func(self.goodbye_message)
+                exit(0)
+            else:
+                if command == self.exit_command:
+                    self.print_func(self.goodbye_message)
+                    exit(0)
+
+
+    def check_is_command_unknown(self, command: str):
+        registered_commands = self.registered_commands
+        for router in registered_commands:
+            for command_entity in router['commands']:
+                if command_entity['command'].lower() == command.lower():
+                    if router['router'].ignore_command_register:
+                        return False
+                    else:
+                        if command_entity['command'] == command:
+                            return False
+        self.main_app_router.unknown_command_handler(command)
+        self.print_func(self.line_separate)
+        self.print_func(self.command_group_description_separate)
+        return True
+
+
+    def print_command_group_description(self):
+        for router in self.registered_commands:
+            self.print_func(router['name'])
+            for command_entity in router['commands']:
+                self.print_func(self._description_message_pattern.format(
+                        command=command_entity['command'],
+                        description=command_entity['description']
+                    )
+                )
+            self.print_func(self.command_group_description_separate)
+
+
+    def include_router(self, router: Router, is_main: bool = False) -> None:
+        if not isinstance(router, Router):
+            raise InvalidRouterInstanceException()
+
+        if is_main:
+            if not self.main_app_router:
+                self.main_app_router = router
+                router.set_router_as_main()
+            else:
+                raise OnlyOneMainRouterIsAllowedException(router)
+
+        self.routers.append(router)
+
+        registered_commands: list[dict[str, Callable[[], None] | str]] = router.get_registered_commands()
+        self.registered_commands.append({'name': router.get_name(),
+                                         'router': router,
+                                         'commands': registered_commands})
+