// zotapi - Rust wrapper for Sot API as implemented by Hubzilla
// Copyright (C) 2018  Harald Eilertsen <haraldei@anduin.net>
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <https://www.gnu.org/licenses/>.

use crate::{
    client::{self, Client},
    error::Error,
};
use serde::{Serialize, Serializer};

pub struct GroupFetcher<'a> {
    client: &'a Client,
}

impl<'a> GroupFetcher<'a> {
    pub fn new(client: &'a Client) -> GroupFetcher<'a> {
        GroupFetcher { client }
    }

    pub fn fetch(&self) -> Result<String, Error> {
        self.client.fetch_stream(client::ZOTAPI_GROUP_PATH, &())
    }
}


enum GroupSelector<'a> {
    Id(u64),
    Name(&'a str),
}

impl<'a> Serialize for GroupSelector<'a> {
    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
    where
        S: Serializer,
    {
        match *self {
            GroupSelector::Id(id) => [("group_id", id)].serialize(serializer),
            GroupSelector::Name(n) => [("group_name", n)].serialize(serializer),
        }
    }
}

pub struct GroupMembersFetcher<'a> {
    client: &'a Client,
    id: Option<GroupSelector<'a>>,
}

impl<'a> GroupMembersFetcher<'a> {
    pub fn new(client: &'a Client) -> GroupMembersFetcher<'a> {
        GroupMembersFetcher { client, id: None }
    }

    pub fn by_group_id(&mut self, id: u64) -> &GroupMembersFetcher<'a> {
        self.id = Some(GroupSelector::Id(id));
        self
    }

    pub fn by_group_name(&mut self, name: &'a str) -> &GroupMembersFetcher<'a> {
        self.id = Some(GroupSelector::Name(name));
        self
    }

    pub fn fetch(&self) -> Result<String, Error> {
        self.client.fetch_stream(
            client::ZOTAPI_GROUP_MEMBERS_PATH,
            &self.id.as_ref().unwrap())
    }
}