/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

//! A task that takes a URL and streams back the binary data.

use about_loader;
use data_loader;
use file_loader;
use http_loader;
use cookie_storage::CookieStorage;
use cookie;
use mime_classifier::MIMEClassifier;

use net_traits::{ControlMsg, LoadData, LoadResponse, LoadConsumer, CookieSource};
use net_traits::{Metadata, ProgressMsg, ResourceTask, AsyncResponseTarget, ResponseAction};
use net_traits::ProgressMsg::Done;
use util::opts;
use util::task::spawn_named;
use url::Url;

use hsts::{HSTSList, HSTSEntry, preload_hsts_domains};

use devtools_traits::{DevtoolsControlMsg};
use hyper::header::{ContentType, Header, SetCookie, UserAgent};
use hyper::mime::{Mime, TopLevel, SubLevel};
use ipc_channel::ipc::{self, IpcReceiver, IpcSender};

use std::borrow::ToOwned;
use std::boxed::FnBox;
use std::sync::Arc;
use std::sync::Mutex;
use std::sync::mpsc::{channel, Sender};

pub enum ProgressSender {
    Channel(IpcSender<ProgressMsg>),
    Listener(AsyncResponseTarget),
}

impl ProgressSender {
    //XXXjdm return actual error
    pub fn send(&self, msg: ProgressMsg) -> Result<(), ()> {
        match *self {
            ProgressSender::Channel(ref c) => c.send(msg).map_err(|_| ()),
            ProgressSender::Listener(ref b) => {
                let action = match msg {
                    ProgressMsg::Payload(buf) => ResponseAction::DataAvailable(buf),
                    ProgressMsg::Done(status) => ResponseAction::ResponseComplete(status),
                };
                b.invoke_with_listener(action);
                Ok(())
            }
        }
    }
}

/// For use by loaders in responding to a Load message.
pub fn start_sending(start_chan: LoadConsumer, metadata: Metadata) -> ProgressSender {
    start_sending_opt(start_chan, metadata).ok().unwrap()
}

/// For use by loaders in responding to a Load message that allows content sniffing.
pub fn start_sending_sniffed(start_chan: LoadConsumer, metadata: Metadata,
                             classifier: Arc<MIMEClassifier>, partial_body: &Vec<u8>)
                             -> ProgressSender {
    start_sending_sniffed_opt(start_chan, metadata, classifier, partial_body).ok().unwrap()
}

/// For use by loaders in responding to a Load message that allows content sniffing.
pub fn start_sending_sniffed_opt(start_chan: LoadConsumer, mut metadata: Metadata,
                                 classifier: Arc<MIMEClassifier>, partial_body: &Vec<u8>)
                                 -> Result<ProgressSender, ()> {
    if opts::get().sniff_mime_types {
        // TODO: should be calculated in the resource loader, from pull requeset #4094
        let mut nosniff = false;
        let mut check_for_apache_bug = false;

        if let Some(ref headers) = metadata.headers {
            if let Some(ref raw_content_type) = headers.get_raw("content-type") {
                if raw_content_type.len() > 0 {
                    let ref last_raw_content_type = raw_content_type[raw_content_type.len() - 1];
                    check_for_apache_bug = last_raw_content_type == b"text/plain"
                                        || last_raw_content_type == b"text/plain; charset=ISO-8859-1"
                                        || last_raw_content_type == b"text/plain; charset=iso-8859-1"
                                        || last_raw_content_type == b"text/plain; charset=UTF-8";
                }
            }
            if let Some(ref raw_content_type_options) = headers.get_raw("X-content-type-options") {
                nosniff = raw_content_type_options.iter().any(|ref opt| *opt == b"nosniff");
            }
        }

        let supplied_type =
            metadata.content_type.map(|ContentType(Mime(toplevel, sublevel, _))| {
            (format!("{}", toplevel), format!("{}", sublevel))
        });
        metadata.content_type = classifier.classify(nosniff, check_for_apache_bug, &supplied_type,
                                                    &partial_body).map(|(toplevel, sublevel)| {
            let mime_tp: TopLevel = toplevel.parse().unwrap();
            let mime_sb: SubLevel = sublevel.parse().unwrap();
            ContentType(Mime(mime_tp, mime_sb, vec!()))
        });

    }

    start_sending_opt(start_chan, metadata)
}

/// For use by loaders in responding to a Load message.
pub fn start_sending_opt(start_chan: LoadConsumer, metadata: Metadata) -> Result<ProgressSender, ()> {
    match start_chan {
        LoadConsumer::Channel(start_chan) => {
            let (progress_chan, progress_port) = ipc::channel().unwrap();
            let result = start_chan.send(LoadResponse {
                metadata:      metadata,
                progress_port: progress_port,
            });
            match result {
                Ok(_) => Ok(ProgressSender::Channel(progress_chan)),
                Err(_) => Err(())
            }
        }
        LoadConsumer::Listener(target) => {
            target.invoke_with_listener(ResponseAction::HeadersAvailable(metadata));
            Ok(ProgressSender::Listener(target))
        }
    }
}

/// Create a ResourceTask
pub fn new_resource_task(user_agent: Option<String>,
                         devtools_chan: Option<Sender<DevtoolsControlMsg>>) -> ResourceTask {
    let hsts_preload = match preload_hsts_domains() {
        Some(list) => list,
        None => HSTSList::new()
    };

    let (setup_chan, setup_port) = ipc::channel().unwrap();
    let setup_chan_clone = setup_chan.clone();
    spawn_named("ResourceManager".to_owned(), move || {
        let resource_manager = ResourceManager::new(
            user_agent, setup_chan_clone, hsts_preload, devtools_chan
        );

        let mut channel_manager = ResourceChannelManager {
            from_client: setup_port,
            resource_manager: resource_manager
        };

        channel_manager.start();
    });
    setup_chan
}

struct ResourceChannelManager {
    from_client: IpcReceiver<ControlMsg>,
    resource_manager: ResourceManager
}

impl ResourceChannelManager {
    fn start(&mut self) {
        loop {
            match self.from_client.recv().unwrap() {
              ControlMsg::Load(load_data, consumer) => {
                  self.resource_manager.load(load_data, consumer)
              }
              ControlMsg::SetCookiesForUrl(request, cookie_list, source) => {
                  self.resource_manager.set_cookies_for_url(request, cookie_list, source)
              }
              ControlMsg::GetCookiesForUrl(url, consumer, source) => {
                  consumer.send(self.resource_manager.cookie_storage.cookies_for_url(&url, source)).unwrap();
              }
              ControlMsg::SetHSTSEntryForHost(host, include_subdomains, max_age) => {
                  if let Some(entry) = HSTSEntry::new(host, include_subdomains, Some(max_age)) {
                      self.resource_manager.add_hsts_entry(entry)
                  }
              }
              ControlMsg::Exit => {
                  break
              }
            }
        }
    }
}

pub struct ResourceManager {
    user_agent: Option<String>,
    cookie_storage: CookieStorage,
    resource_task: IpcSender<ControlMsg>,
    mime_classifier: Arc<MIMEClassifier>,
    devtools_chan: Option<Sender<DevtoolsControlMsg>>,
    hsts_list: Arc<Mutex<HSTSList>>
}

impl ResourceManager {
    pub fn new(user_agent: Option<String>,
               resource_task: IpcSender<ControlMsg>,
               hsts_list: HSTSList,
               devtools_channel: Option<Sender<DevtoolsControlMsg>>) -> ResourceManager {
        ResourceManager {
            user_agent: user_agent,
            cookie_storage: CookieStorage::new(),
            resource_task: resource_task,
            mime_classifier: Arc::new(MIMEClassifier::new()),
            devtools_chan: devtools_channel,
            hsts_list: Arc::new(Mutex::new(hsts_list))
        }
    }
}

impl ResourceManager {
    fn set_cookies_for_url(&mut self, request: Url, cookie_list: String, source: CookieSource) {
        let header = Header::parse_header(&[cookie_list.into_bytes()]);
        if let Ok(SetCookie(cookies)) = header {
            for bare_cookie in cookies.into_iter() {
                if let Some(cookie) = cookie::Cookie::new_wrapped(bare_cookie, &request, source) {
                    self.cookie_storage.push(cookie, source);
                }
            }
        }
    }

    pub fn add_hsts_entry(&mut self, entry: HSTSEntry) {
        self.hsts_list.lock().unwrap().push(entry);
    }

    pub fn is_host_sts(&self, host: &str) -> bool {
        self.hsts_list.lock().unwrap().is_host_secure(host)
    }

    fn load(&mut self, mut load_data: LoadData, consumer: LoadConsumer) {
        self.user_agent.as_ref().map(|ua| {
            load_data.preserved_headers.set(UserAgent(ua.clone()));
        });

        fn from_factory(factory: fn(LoadData, LoadConsumer, Arc<MIMEClassifier>))
                        -> Box<FnBox(LoadData, LoadConsumer, Arc<MIMEClassifier>) + Send> {
            box move |load_data, senders, classifier| {
                factory(load_data, senders, classifier)
            }
        }

        let loader = match &*load_data.url.scheme {
            "file" => from_factory(file_loader::factory),
            "http" | "https" | "view-source" =>
                http_loader::factory(self.resource_task.clone(), self.devtools_chan.clone(), self.hsts_list.clone()),
            "data" => from_factory(data_loader::factory),
            "about" => from_factory(about_loader::factory),
            _ => {
                debug!("resource_task: no loader for scheme {}", load_data.url.scheme);
                start_sending(consumer, Metadata::default(load_data.url))
                    .send(ProgressMsg::Done(Err("no loader for scheme".to_string()))).unwrap();
                return
            }
        };
        debug!("resource_task: loading url: {}", load_data.url.serialize());

        loader.call_box((load_data, consumer, self.mime_classifier.clone()));
    }
}