// 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 error::Error;
use item::ItemBuilder;
use reqwest::{
    self,
    header::{ACCEPT, CONTENT_TYPE},
    StatusCode,
};
use serde::Serialize;
use serde_urlencoded;
use std::io::Read;
use xchan::XChanFetcher;

pub const ZOTAPI_CHANNEL_STREAM_PATH : &str = "/api/z/1.0/channel/stream";
pub const ZOTAPI_NETWORK_STREAM_PATH : &str = "/api/z/1.0/network/stream";
pub const ZOTAPI_ITEM_UPDATE_PATH : &str = "/api/z/1.0/item/update";
pub const ZOTAPI_XCHAN_PATH : &str = "/api/z/1.0/xchan";

pub struct Client {
    inner: reqwest::Client,
    base_url: String,
    user: String,
    pw: String,
}

impl Client {
    pub fn new(url: &str, user: &str, pw: &str) -> Client {
        Client {
            inner: reqwest::Client::new(),
            base_url: String::from(url),
            user: String::from(user),
            pw: String::from(pw),
        }
    }

    pub fn channel_stream(&self) -> Result<String, Error> {
        self.fetch_stream(ZOTAPI_CHANNEL_STREAM_PATH, &())
    }

    pub fn network_stream(&self) -> Result<String, Error> {
        self.fetch_stream(ZOTAPI_NETWORK_STREAM_PATH, &())
    }

    pub fn item(&self) -> ItemBuilder {
        ItemBuilder::new(self)
    }

    pub fn xchan(&self) -> XChanFetcher {
        XChanFetcher::new(self)
    }

    fn url<T>(&self, path: &str, args: &T) -> String
        where T: Serialize
    {
        let r = self.base_url.clone() + path;
        if let Ok(a) = serde_urlencoded::to_string(args) {
            r + "?" + &a
        }
        else {
            r
        }
    }

    pub fn fetch_stream<T>(&self, path: &str, args: &T) -> Result<String, Error>
        where T: Serialize
    {
        let url = self.url(path, args);
        let mut res = self.inner.get(&url)
            .header(ACCEPT, "application/json")
            .basic_auth(self.user.clone(), Some(self.pw.clone()))
            .send()?;

        match res.status() {
            StatusCode::UNAUTHORIZED => Err(Error::Unauthorized),
            StatusCode::OK => {
                let mut body = String::new();
                res.read_to_string(&mut body)?;
                Ok(body)
            },
            _ => {
                println!("Received unknown status: {:?}", res.status());
                Err(Error::Unknown)
            }
        }
    }

    pub fn post_data<T>(&self, path: &str, data: &T) -> Result<String, Error>
        where T: Serialize,
    {
        let url = self.url(path, &());
        let mut res = self.inner.post(&url)
            .header(ACCEPT, "application/json")
            .header(CONTENT_TYPE, "application/x-www-form-urlencoded")
            .basic_auth(self.user.clone(), Some(self.pw.clone()))
            .form(&data)
            .send()?;

        match res.status() {
            StatusCode::UNAUTHORIZED => Err(Error::Unauthorized),
            StatusCode::OK => {
                let mut body = String::new();
                res.read_to_string(&mut body)?;
                Ok(body)
            },
            _ => Err(Error::Unknown)
        }
    }
}