from typing import Optional

from sqlalchemy.orm import Session

from app.application.courses_repository import CoursesRepository
from app.domain.entities.courses_entity import CourseEntity
from app.domain.models.courses import Course


class CoursesService:
    def __init__(self, db: Session):
        self.courses_repository = CoursesRepository(db)

    def get_all(self) -> list[CourseEntity]:
        courses = self.courses_repository.get_all()
        return [
            CourseEntity(
                id=course.id,
                title=course.title,
                description=course.description,
                category_id=course.category_id,
                owner_user_id=course.owner_user_id,
            ) for course in courses
        ]

    def get_by_id(self, course_id: int) -> Optional[CourseEntity]:
        course = self.courses_repository.get_by_id(course_id)
        if course:
            return CourseEntity(
                id=course.id,
                title=course.title,
                description=course.description,
                category_id=course.category_id,
                owner_user_id=course.owner_user_id,
            )

        return None

    def create(self, course: CourseEntity) -> CourseEntity:
        course_model = Course(
            title=course.title,
            description=course.description,
            category_id=course.category_id,
            owner_user_id=course.owner_user_id,
        )
        created_course = self.courses_repository.create(course_model)
        return CourseEntity(
            id=created_course.id,
            title=created_course.title,
            description=created_course.description,
            category_id=created_course.category_id,
            owner_user_id=created_course.owner_user_id,
        )

    def update(self, course_id: int, course: CourseEntity) -> Optional[CourseEntity]:
        course_model = self.courses_repository.get_by_id(course_id)
        if course_model:
            course_model.title = course.title
            course_model.description = course.description
            course_model.category_id = course.category_id
            course_model.owner_user_id = course.owner_user_id
            updated_course = self.courses_repository.update(course_model)
            return CourseEntity(
                id=updated_course.id,
                title=updated_course.title,
                description=updated_course.description,
                category_id=updated_course.category_id,
                owner_user_id=updated_course.owner_user_id,
            )

        return None

    def delete(self, course_id: int) -> bool:
        return self.courses_repository.delete(course_id) is not None