#![feature(plugin, decl_macro)]
#![plugin(rocket_codegen)]

#[macro_use] extern crate rocket;
#[macro_use] extern crate lazy_static;
#[macro_use] extern crate json;
extern crate rocket_cors;

#[macro_use]
extern crate serde_json;
extern crate json_patch;

use std::io::prelude::*;
use std::fs::File;
use std::path::{Path, PathBuf};
use std::thread;
use std::time::Duration;
use std::sync::Mutex;
use rocket::response::NamedFile;

use json_patch::patch;
use serde_json::from_str;
use serde_json::to_string;
use json_patch::merge;

lazy_static! {
    static ref OBJECT: Mutex<String> = Mutex::new(String::from("{}"));
}

// send out the stored object
#[get("/")]
fn get() -> String {
    match OBJECT.lock() {
        Ok(obj) => {
            println!("MATCH obj {:?}", *obj);
            let result: &String = &*obj;
            result.clone()
        },
        _ => {
            println!("UNLOCK failed");
            String::from("{}")
        }
    }
}

//set the storage
#[get("/<obj>")]
fn set(obj: String) -> String {



    // let json_result = json::parse(obj.to_owned().as_str());
    // let json_result: serde_json::Value = from_str(obj.to_owned().as_str());
    let json_result: Result<serde_json::Value, serde_json::Error> = from_str(obj.to_owned().as_str());

    match json_result {
        Ok(json_from_web) => {
            let mut locked_obj = OBJECT.lock().unwrap();
            // let current_object = json::parse(&locked_obj);
            let mut parsed_object: Result<serde_json::Value, serde_json::Error> = from_str(&locked_obj);
            
            match parsed_object {
                Ok(mut json_object) => {
                    println!("{:?}", json_object);
                    merge(&mut json_object, &json_from_web);
                    *locked_obj = to_string(&json_object).unwrap();
                    println!("JSON MERGE {:?}", json_object);

                },
                Err(e) => {
                    // The db is somehow corrupted, just put in what we got from the web
                    println!("Invalid json in db {:?}", e);
                    *locked_obj = to_string(&json_from_web).unwrap();
                }
            }

            println!("GOT {:?}", obj);
            println!("JSON INCOMING {:?}", json_from_web);
            String::from("Done")
        },
        Err(_e) => String::from("Invalid Json")
    }

}

// Static file serving
#[get("/<file..>")]
fn static_content(file: PathBuf) -> NamedFile {
    let f = NamedFile::open(Path::new("static/").join(file));
    match f {
        Ok(result) => result,
        Err(_e) => NamedFile::open("static/err.html").unwrap()
    }
}

// periodically dump the database
fn disk_committer() {
    thread::spawn(|| {
        loop {
            thread::sleep(Duration::from_secs(2));
            match OBJECT.lock() {
                Ok(obj) => {
                    let result: &String = &*obj;
                    let mut buffer = File::create("db").unwrap();
                    buffer.write(result.as_bytes()).unwrap();
                    // println!("Committing to disk");
                },
                _ => ()
            }
        }
    });
}

fn read_db() {    
    let dbfile = File::open("db");
    match dbfile {
        Ok(mut f) => {
            let mut contents = String::new();
            f.read_to_string(&mut contents).expect("{}");
            let mut data = OBJECT.lock().unwrap();
            *data = contents;
        },
        Err(e) => println!("Could not load db file {:?}", e)
    }
}

fn main() {

    // let (allowed_origins, failed_origins) = AllowedOrigins::some(&["https://www.acme.com"]);
    // assert!(failed_origins.is_empty());

    // // You can also deserialize this
    // let options = rocket_cors::Cors {
    //     allowed_origins: allowed_origins,
    //     allowed_methods: vec![Method::Get].into_iter().map(From::from).collect(),
    //     allowed_headers: AllowedHeaders::some(&["Authorization", "Accept"]),
    //     allow_credentials: true,
    //     ..Default::default()
    // };

    // let default = rocket_cors::Cors::default();

    // Load from db
    read_db();
    disk_committer();
    rocket::ignite()
    .mount("/set", routes![set])
    .mount("/get", routes![get])
    // .mount("/test", routes![test])
    .mount("/static", routes![static_content])
    // .attach(default)
    .launch();
}