use std::{
    fmt::{Debug, Display},
    str::FromStr,
};

use anyhow::Error;

use crate::{
    error::{GetValueError, OperationError},
    object_backend::ObjectBackend,
    operation::{GiteratedOperation, OperationState},
    settings::{GetSetting, GetSettingError, SetSetting, SetSettingError, Setting},
    value::{GetValue, GiteratedObjectValue},
};

mod operations;
pub use operations::*;

#[derive(Debug, Clone)]
pub struct Object<O: GiteratedObject, B: ObjectBackend + Send + Clone> {
    pub(crate) inner: O,
    pub(crate) backend: B,
}

impl<B: ObjectBackend + Send + Sync + Clone, O: GiteratedObject> Object<O, B> {
    pub fn object(&self) -> &O {
        &self.inner
    }

    pub unsafe fn new_unchecked(object: O, backend: B) -> Object<O, B> {
        Object {
            inner: object,
            backend,
        }
    }
}

impl<O: GiteratedObject + Display, B: ObjectBackend + Send + Sync + Clone> Display
    for Object<O, B>
{
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        self.inner.fmt(f)
    }
}

pub trait GiteratedObject: Send + Display + FromStr + Sync + Clone {
    fn object_name() -> &'static str;
    fn home_uri(&self) -> String;

    fn from_object_str(object_str: &str) -> Result<Self, Error>;
}

impl<O: GiteratedObject + Clone + Debug + 'static, B: ObjectBackend> Object<O, B> {
    pub async fn get<V: GiteratedObjectValue<Object = O> + Send + Debug + 'static>(
        &mut self,
        operation_state: &OperationState,
    ) -> Result<V, OperationError<GetValueError>> {
        let result = self
            .request(
                GetValue {
                    value_name: V::value_name().to_string(),
                },
                operation_state,
            )
            .await?;

        Ok(serde_json::from_slice(&result).unwrap())
    }

    pub async fn get_setting<S: Setting + Send + Clone + Debug>(
        &mut self,
        operation_state: &OperationState,
    ) -> Result<S, OperationError<GetSettingError>> {
        self.request(
            GetSetting {
                setting_name: S::name().to_string(),
            },
            operation_state,
        )
        .await
        .map(|success| serde_json::from_value(success).unwrap())
    }

    pub async fn set_setting<S: Setting + Send + Clone + Debug>(
        &mut self,
        setting: S,
        operation_state: &OperationState,
    ) -> Result<(), OperationError<SetSettingError>> {
        self.request(
            SetSetting {
                setting_name: S::name().to_string(),
                value: serde_json::to_value(setting).unwrap(),
            },
            operation_state,
        )
        .await
    }

    pub async fn request<R: GiteratedOperation<O> + Debug + 'static>(
        &mut self,
        request: R,
        operation_state: &OperationState,
    ) -> Result<R::Success, OperationError<R::Failure>>
    where
        R::Success: Clone,
        R::Failure: Clone,
    {
        self.backend
            .object_operation(
                self.inner.clone(),
                R::operation_name(),
                request,
                operation_state,
            )
            .await
    }
}