use indicatif::{ProgressBar, ProgressStyle};
use reqwest::blocking::Client;
use std::sync::{Arc, Mutex};
use std::thread;
use std::time::Duration;

const ACCESS_TOKEN: &str = "YOUR_CANVAS_API_TOKEN";
const BASE_URL: &str = "https://unt.instructure.com/api/v1/files";
const CENTER_ID: u64 = 37826490;
const RADIUS: u64 = 200000;
const NUM_WORKERS: usize = 20;

/// Pause all workers when quota drops to or below this value.
const RATE_LIMIT_PAUSE_THRESHOLD: f64 = 50.0;
/// Resume once quota recovers above this value (Canvas resets the window automatically).
const RATE_LIMIT_RESUME_THRESHOLD: f64 = 200.0;
/// How long each paused worker sleeps before re-checking.
const RATE_LIMIT_SLEEP_MS: u64 = 2000;

fn parse_rate_limit(resp: &reqwest::blocking::Response) -> Option<f64> {
    resp.headers()
        .get("x-rate-limit-remaining")?
        .to_str()
        .ok()?
        .parse::<f64>()
        .ok()
}

fn main() {
    let start = CENTER_ID - RADIUS;
    let end = CENTER_ID + RADIUS;
    let ids: Vec<u64> = (start..=end).collect();
    let total = ids.len() as u64;

    let pb = ProgressBar::new(total);
    pb.set_style(
        ProgressStyle::with_template(
            "[{percent:>3}%] {spinner:.cyan} | {pos}/{len} IDs | elapsed {elapsed_precise} | ETA {eta_precise} | RL: {msg} {bar:25.green/white}",
        )
        .unwrap()
        .progress_chars("█▉▊▋▌▍▎▏  ")
        .tick_chars("|/-\\"),
    );
    pb.set_message("---");
    pb.enable_steady_tick(Duration::from_millis(100));

    let ids = Arc::new(Mutex::new(ids.into_iter()));
    let pb = Arc::new(pb);
    let found: Arc<Mutex<Vec<(u64, String)>>> = Arc::new(Mutex::new(Vec::new()));

    // Shared rate-limit state across all workers.
    let rate_limit_remaining: Arc<Mutex<f64>> = Arc::new(Mutex::new(f64::MAX));

    let mut handles = vec![];

    for _ in 0..NUM_WORKERS {
        let ids = Arc::clone(&ids);
        let pb = Arc::clone(&pb);
        let found = Arc::clone(&found);
        let rl = Arc::clone(&rate_limit_remaining);

        let handle = thread::spawn(move || {
            let client = Client::builder()
                .timeout(Duration::from_secs(15))
                .build()
                .expect("Failed to build HTTP client");

            loop {
                // --- Rate-limit gate: pause until quota recovers ---
                loop {
                    let remaining = *rl.lock().unwrap();
                    if remaining > RATE_LIMIT_PAUSE_THRESHOLD {
                        break;
                    }
                    pb.set_message(format!("PAUSED ({:.0} left)", remaining));
                    thread::sleep(Duration::from_millis(RATE_LIMIT_SLEEP_MS));
                    // Optimistically let one thread probe the server to check
                    // if the Canvas window has reset.
                    let mut r = rl.lock().unwrap();
                    if *r <= RATE_LIMIT_PAUSE_THRESHOLD {
                        *r = RATE_LIMIT_RESUME_THRESHOLD;
                    }
                }

                // --- Pull next ID ---
                let id = {
                    let mut iter = ids.lock().unwrap();
                    iter.next()
                };
                let id = match id {
                    Some(id) => id,
                    None => break,
                };

                let url = format!("{}/{}?access_token={}", BASE_URL, id, ACCESS_TOKEN);

                // HEAD request to check existence + read rate-limit header
                let head_resp = client.head(&url).send();

                if let Ok(resp) = head_resp {
                    // Update shared quota from every response
                    if let Some(remaining) = parse_rate_limit(&resp) {
                        let mut r = rl.lock().unwrap();
                        *r = remaining;
                        pb.set_message(format!("{:.0}", remaining));
                    }

                    if resp.status().is_success() {
                        // GET to retrieve display_name
                        if let Ok(get_resp) = client.get(&url).send() {
                            if let Some(remaining) = parse_rate_limit(&get_resp) {
                                let mut r = rl.lock().unwrap();
                                *r = remaining;
                                pb.set_message(format!("{:.0}", remaining));
                            }
                            if let Ok(json) = get_resp.json::<serde_json::Value>() {
                                let name = json["display_name"]
                                    .as_str()
                                    .unwrap_or("<unknown>")
                                    .to_string();
                                pb.println(format!("FOUND: {}. Name: {}", id, name));
                                found.lock().unwrap().push((id, name));
                            }
                        }
                    }
                }

                pb.inc(1);
            }
        });

        handles.push(handle);
    }

    for h in handles {
        h.join().expect("Worker thread panicked");
    }

    pb.finish_with_message("done");

    let found = found.lock().unwrap();
    println!("\n=== Results ({} found) ===", found.len());
    for (id, name) in found.iter() {
        println!("  ID {}: {}", id, name);
    }
}

trait ATrait {
    fn a(&mut self) -> &mut A{
        self.a()
    }
    fn b(&mut self) -> &mut i64{
        return self.a().b()
    }
}
struct A {
    b: i64
}
impl ATrait for A {
    fn a(&mut self) -> &mut A{
        self
    }
    fn b(&mut self) -> &mut i64{
        &mut self.b
    }
}

struct B {
    a: A,
    c: i64
}

impl ATrait for B{
    fn a(&mut self) -> &mut A{
        self.a.a()
    }
}



fn main() {
    let mut b: B = B{
        a: A {b: 2},
        c: 3
    };
    println!("{}", b.b());
}

struct Beer {
    bottles: i32,
}

impl Beer {
    fn new() -> Beer {
        Beer { bottles: 99 }
    }

    fn take_one_down(&mut self) {
        self.bottles -= 1;
    }

    fn no_more(&self) -> bool {
        self.bottles == 0
    }

    fn go_to_the_store(&mut self) {
        self.bottles = 99;
    }

    fn to_string(&self) -> String {
        match self.bottles {
            0 => "No more bottles".to_string(), //Reaized this is incorrect because the N could be lowercase. But technically the comma in the beer song is incorrect because it separates two whole sentences and should be a comma
            1 => "1 bottle".to_string(),
            _ => format!("{} bottles", self.bottles),
        }
    }
}

fn main() {
    let mut bottles: Beer = Beer::new();
    
    let KEEP_GOING: bool = true;
    
    let FOREVER: bool = false;
    
    let MAX_LOOPS: i32 = 2;
    
    let mut int: i32 = 0;
    
    while FOREVER | (int < MAX_LOOPS){
        print!("{} of beer on the wall, ", bottles.to_string());
        println!("{} of beer.", bottles.to_string());
        if !bottles.no_more(){
            print!("Take one down, pass it around, ");
            bottles.take_one_down();
            println!("{} of beer on the wall.", bottles.to_string());
            println!();
        } else {
            print!("Go to the store and buy some more, ");
            bottles.go_to_the_store();
            println!("{} of beer on the wall.", bottles.to_string());
            if(!KEEP_GOING){
                break; //Comment this out to keep it going
            }else{
                println!();
                int += 1;
            }
        }
    }
}