// Copyright 2015-2018 Capital One Services, LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

//! # wascap-codec
//! 
//! This library provides the core set of types and associated functions used to facilitate guest module
//! and host runtime communication for Waxosuit. 

use prost_types;

#[macro_use]
extern crate serde_derive;

macro_rules! command {
    ($msgid:ident, $typ:ty) => {
        impl crate::AsCommand for $typ {
            fn as_command(&self, source: &str, target_cap: &str) -> crate::core::Command {
                crate::create_command(self, $msgid, source, target_cap)
            }
        }
    };
}

macro_rules! event {
    ($msgid:ident, $typ:ty) => {
        impl crate::AsEvent for $typ {
            fn as_event(&self, success: bool, error: Option<(i32, &str)>) -> crate::core::Event {
                crate::create_event(Some(self), $msgid, success, error)
            }
        }
    };
}

pub mod http {
    //! # HTTP server capability data structures
    //! 
    //! This module contains data types for the `wascap:http_server` capability.
    include!(concat!(env!("OUT_DIR"), "/http.rs"));

    use prost::Message;
    use serde::ser::Serialize;
    use std::collections::HashMap;

    pub const TYPE_URL_HTTP_REQUEST: &'static str = "type.wascap.io/http.Request";
    pub const TYPE_URL_HTTP_RESPONSE: &'static str = "type.wascap.io/http.Response";

    command!(TYPE_URL_HTTP_REQUEST, Request);
    event!(TYPE_URL_HTTP_RESPONSE, Response);

    impl Into<Request> for &[u8] {
        fn into(self) -> Request {
            Request::decode(self).unwrap()
        }
    }

    impl Into<Response> for &[u8] {
        fn into(self) -> Response {
            Response::decode(self).unwrap()
        }
    }

    impl Response {
        /// Creates a response with a given status code and serializes the given payload as JSON
        pub fn json<T>(payload: T, status_code: u32, status: &str) -> Response
        where
            T: Serialize,
        {
            Response {
                body: serde_json::to_string(&payload).unwrap().into_bytes(),
                header: HashMap::new(),
                status: status.to_string(),
                status_code: status_code,
            }
        }

        /// Handy shortcut for creating a 404/Not Found response
        pub fn not_found() -> Response {
            Response {
                status: "Not Found".to_string(),
                status_code: 404,
                ..Default::default()
            }
        }

        /// Useful shortcut for creating a 200/OK response
        pub fn ok() -> Response {
            Response {
                status: "OK".to_string(),
                status_code: 200,
                ..Default::default()
            }
        }

        /// Useful shortcut for creating a 500/Internal Server Error response
        pub fn internal_server_error(msg: &str) -> Response {
            Response {
                status: "Internal Server Error".to_string(),
                status_code: 500,
                body: msg.to_string().as_bytes().into(),
                ..Default::default()
            }
        }

        /// Shortcut for creating a 400/Bad Request response
        pub fn bad_request() -> Response {
            Response {
                status: "Bad Request".to_string(),
                status_code: 400,
                ..Default::default()
            }
        }
    }
}

pub mod core {
//! # Core data types
//! 
//! This module contains data types used for Wascap guest module and host runtime communications
    include!(concat!(env!("OUT_DIR"), "/core.rs"));

    pub const TYPE_URL_LIVE_UPDATE: &'static str = "type.wascap.io/core.LiveUpdate";
    pub const TYPE_URL_HEALTH_REQUEST: &'static str = "type.wascap.io/core.HealthRequest";

    command!(TYPE_URL_LIVE_UPDATE, LiveUpdate);
    command!(TYPE_URL_HEALTH_REQUEST, HealthRequest);

    impl Event {
        pub fn bad_dispatch(type_url: &str) -> Event {
            Event {
                success: false,
                payload: None,
                error: Some(Error {
                    code: -100,
                    description: format!("Guest module rejected command: {}", type_url),
                }),
            }
        }

        pub fn success() -> Event {
            Event {
                success: true,
                payload: None,
                error: None,
            }
        }
    }
}

pub mod messaging {
//! # Message Broker Data Types
//! 
//! This module contains data types for the `wascap:messaging` capability provider
    use prost::Message;

    include!(concat!(env!("OUT_DIR"), "/messaging.rs"));

    pub const TYPE_URL_DELIVER_MESSAGE: &'static str = "type.wascap.io/messaging.DeliverMessage";
    pub const TYPE_URL_PUBLISH_MESSAGE: &'static str = "type.wascap.io/messaging.PublishMessage";

    impl Into<DeliverMessage> for &Vec<u8> {
        fn into(self) -> DeliverMessage {
            DeliverMessage::decode(self.as_slice()).unwrap()
        }
    }

    impl Into<PublishMessage> for &Vec<u8> {
        fn into(self) -> PublishMessage {
            PublishMessage::decode(self.as_slice()).unwrap()
        }
    }

    command!(TYPE_URL_DELIVER_MESSAGE, DeliverMessage);
    command!(TYPE_URL_PUBLISH_MESSAGE, PublishMessage);
}

pub mod keyvalue {
//! # Key-Value Store Data Types
//! 
//! This module contains data types for the `wascap:keyvalue` capability provider
    include!(concat!(env!("OUT_DIR"), "/keyvalue.rs"));

    pub const TYPE_URL_GET_REQUEST: &'static str = "type.wascap.io/keyvalue.GetRequest";
    pub const TYPE_URL_GET_RESPONSE: &'static str = "type.wascap.io/keyvalue.GetResponse";
    pub const TYPE_URL_SET_REQUEST: &'static str = "type.wascap.io/keyvalue.SetRequest";
    pub const TYPE_URL_ADD_REQUEST: &'static str = "type.wascap.io/keyvalue.AddRequest";
    pub const TYPE_URL_ADD_RESPONSE: &'static str = "type.wascap.io/keyvalue.AddResponse";
    pub const TYPE_URL_LIST_PUSH_REQUEST: &'static str = "type.wascap.io/keyvalue.ListPushRequest";
    pub const TYPE_URL_LIST_RESPONSE: &'static str = "type.wascap.io/keyvalue.ListResponse";
    pub const TYPE_URL_LIST_CLEAR_REQUEST: &'static str =
        "type.wascap.io/keyvalue.ListClearRequest";
    pub const TYPE_URL_LIST_RANGE_REQUEST: &'static str =
        "type.wascap.io/keyvalue.ListRangeRequest";
    pub const TYPE_URL_LIST_RANGE_RESPONSE: &'static str =
        "type.wascap.io/keyvalue.ListRangeResponse";
    pub const TYPE_URL_DEL_REQUEST: &'static str = "type.wascap.io/keyvalue.DelRequest";

    command!(TYPE_URL_GET_REQUEST, GetRequest);
    event!(TYPE_URL_GET_RESPONSE, GetResponse);
    command!(TYPE_URL_SET_REQUEST, SetRequest);
    command!(TYPE_URL_ADD_REQUEST, AddRequest);
    event!(TYPE_URL_ADD_RESPONSE, AddResponse);
    command!(TYPE_URL_LIST_PUSH_REQUEST, ListPushRequest);
    event!(TYPE_URL_LIST_RESPONSE, ListResponse);
    command!(TYPE_URL_LIST_CLEAR_REQUEST, ListClearRequest);
    command!(TYPE_URL_LIST_RANGE_REQUEST, ListRangeRequest);
    event!(TYPE_URL_LIST_RANGE_RESPONSE, ListRangeResponse);
    command!(TYPE_URL_DEL_REQUEST, DelRequest);

}

/// A trait that allows a protobuf message to be wrapped as a payload inside a command
pub trait AsCommand {
    fn as_command(&self, source: &str, target_cap: &str) -> crate::core::Command;
}

/// A trait that allows a protobuf message to be wrapped as a payload inside an event
pub trait AsEvent {
    fn as_event(&self, success: bool, error: Option<(i32, &str)>) -> crate::core::Event;
}

pub mod capabilities;

pub fn pack_any(msg: &impl prost::Message, type_url: &str) -> prost_types::Any {
    let mut v = Vec::with_capacity(msg.encoded_len());
    msg.encode(&mut v).unwrap();
    prost_types::Any {
        type_url: type_url.to_string(),
        value: v,
    }
}

/// Creates a new `Command` from any arbitrary protobuf message 
pub fn create_command(
    msg: &impl prost::Message,
    type_url: &str,
    source: &str,
    target_cap: &str,
) -> crate::core::Command {
    let any = pack_any(msg, type_url);

    crate::core::Command {
        source: source.to_string(),
        target_cap: target_cap.to_string(),
        payload: Some(any),
    }
}

/// Creates a new `Event` from any arbitrary protobuf message
pub fn create_event(
    msg: Option<&impl prost::Message>,
    type_url: &str,
    success: bool,
    error: Option<(i32, &str)>,
) -> crate::core::Event {
    let any = msg.map(|m| pack_any(m, type_url));

    crate::core::Event {
        success,
        payload: any,
        error: error.map(|(c, d)| crate::core::Error {
            description: d.to_string(),
            code: c,
        }),
    }
}