use anyhow::Result;
use crossterm::event::{self, Event, KeyCode, KeyModifiers};
use std::{
    sync::{
        atomic::{AtomicBool, AtomicU64, Ordering},
        Arc,
    },
    time::Duration,
};

pub type AbortSignal = Arc<AbortSignalInner>;

#[derive(Debug, Default)]
pub struct QueryIdGen {
    counter: AtomicU64,
    parents: parking_lot::RwLock<std::collections::HashMap<String, u64>>,
}

impl QueryIdGen {
    pub fn root_id(&self) -> u64 {
        self.counter.fetch_add(1, Ordering::SeqCst)
    }

    pub fn child_id(&self, parent_path: &[u64]) -> u64 {
        if parent_path.is_empty() {
            return self.root_id();
        }
        let key = parent_path
            .iter()
            .map(|v| v.to_string())
            .collect::<Vec<_>>()
            .join("/");
        let mut parents = self.parents.write();
        let entry = parents.entry(key).or_insert(0);
        let id = *entry;
        *entry += 1;
        id
    }
}

pub fn format_query_path(path: &[u64]) -> String {
    if path.is_empty() {
        return String::new();
    }
    format!(
        "[{}]",
        path.iter()
            .map(|v| v.to_string())
            .collect::<Vec<_>>()
            .join("/")
    )
}

tokio::task_local! {
    static QUERY_SCOPE: String;
    static QUERY_ID_GEN: QueryIdGen;
}

pub fn current_query_scope() -> Option<String> {
    QUERY_SCOPE
        .try_with(|v| if v.is_empty() { None } else { Some(v.clone()) })
        .ok()
        .flatten()
}

pub async fn with_query_scope<F: std::future::Future>(scope: String, future: F) -> F::Output {
    QUERY_SCOPE.scope(scope, future).await
}

pub fn next_query_id(parent_path: &[u64]) -> u64 {
    if parent_path.is_empty() {
        return QUERY_ID_GEN.try_with(|g| g.root_id()).unwrap_or(0);
    }
    QUERY_ID_GEN
        .try_with(|g| g.child_id(parent_path))
        .unwrap_or(0)
}

pub struct AbortSignalInner {
    ctrlc: AtomicBool,
    ctrld: AtomicBool,
}

pub fn create_abort_signal() -> AbortSignal {
    AbortSignalInner::new()
}

impl AbortSignalInner {
    pub fn new() -> AbortSignal {
        Arc::new(Self {
            ctrlc: AtomicBool::new(false),
            ctrld: AtomicBool::new(false),
        })
    }

    pub fn aborted(&self) -> bool {
        if self.aborted_ctrlc() {
            return true;
        }
        if self.aborted_ctrld() {
            return true;
        }
        false
    }

    pub fn aborted_ctrlc(&self) -> bool {
        self.ctrlc.load(Ordering::SeqCst)
    }

    pub fn aborted_ctrld(&self) -> bool {
        self.ctrld.load(Ordering::SeqCst)
    }

    pub fn reset(&self) {
        self.ctrlc.store(false, Ordering::SeqCst);
        self.ctrld.store(false, Ordering::SeqCst);
    }

    pub fn set_ctrlc(&self) {
        self.ctrlc.store(true, Ordering::SeqCst);
    }

    pub fn set_ctrld(&self) {
        self.ctrld.store(true, Ordering::SeqCst);
    }
}

pub async fn wait_abort_signal(abort_signal: &AbortSignal) {
    loop {
        if abort_signal.aborted() {
            break;
        }
        tokio::time::sleep(std::time::Duration::from_millis(25)).await;
    }
}

pub fn poll_abort_signal(abort_signal: &AbortSignal) -> Result<bool> {
    if crossterm::event::poll(Duration::from_millis(25))? {
        if let Event::Key(key) = event::read()? {
            match key.code {
                KeyCode::Char('c') if key.modifiers == KeyModifiers::CONTROL => {
                    abort_signal.set_ctrlc();
                    return Ok(true);
                }
                KeyCode::Char('d') if key.modifiers == KeyModifiers::CONTROL => {
                    abort_signal.set_ctrld();
                    return Ok(true);
                }
                _ => {}
            }
        }
    }
    Ok(false)
}