use std::path::PathBuf;
use std::sync::Arc;
use tokio::sync::RwLock;
use super::types::Overlay;

#[derive(Clone)]
pub struct DirCache {
    entries: Arc<RwLock<Vec<PathBuf>>>,
}

impl DirCache {
    pub fn new() -> Self {
        DirCache {
            entries: Arc::new(RwLock::new(Vec::new())),
        }
    }

    pub async fn set(&self, paths: Vec<PathBuf>) {
        let mut w = self.entries.write().await;
        *w = paths;
    }

    pub async fn get(&self) -> Vec<PathBuf> {
        let r = self.entries.read().await;
        r.clone()
    }
}

#[derive(Debug, Clone)]
pub struct ScrollState {
    pub offset: usize,
    pub max_visible: usize,
}

impl ScrollState {
    pub fn new() -> Self {
        ScrollState {
            offset: 0,
            max_visible: 30,
        }
    }

    pub fn scroll_up(&mut self) {
        if self.offset > 0 {
            self.offset -= 1;
        }
    }

    pub fn scroll_down(&mut self, total: usize) {
        let max_offset = total.saturating_sub(self.max_visible);
        if self.offset < max_offset {
            self.offset += 1;
        }
    }

    pub fn scroll_to_bottom(&mut self, total: usize) {
        self.offset = total.saturating_sub(self.max_visible);
    }

    pub fn set_max_visible(&mut self, max: usize) {
        self.max_visible = max;
    }
}

#[derive(Debug, Clone)]
pub struct InputState {
    pub buffer: String,
    pub cursor: usize,
    pub history: Vec<String>,
    pub history_idx: Option<usize>,
}

impl InputState {
    pub fn new() -> Self {
        InputState {
            buffer: String::new(),
            cursor: 0,
            history: Vec::new(),
            history_idx: None,
        }
    }

    pub fn char_left(&mut self) {
        if self.cursor > 0 {
            self.cursor -= 1;
        }
    }

    pub fn char_right(&mut self) {
        if self.cursor < self.buffer.len() {
            self.cursor += 1;
        }
    }

    pub fn insert(&mut self, c: char) {
        self.buffer.insert(self.cursor, c);
        self.cursor += 1;
    }

    pub fn delete_left(&mut self) {
        if self.cursor > 0 {
            self.cursor -= 1;
            self.buffer.remove(self.cursor);
        }
    }

    pub fn delete_right(&mut self) {
        if self.cursor < self.buffer.len() {
            self.buffer.remove(self.cursor);
        }
    }

    pub fn submit(&mut self) -> String {
        let result = self.buffer.clone();
        if !result.is_empty() {
            self.history.push(result.clone());
            self.history_idx = None;
        }
        self.buffer.clear();
        self.cursor = 0;
        result
    }

    pub fn history_up(&mut self) {
        if self.history.is_empty() {
            return;
        }
        let idx = match self.history_idx {
            Some(i) if i > 0 => i - 1,
            None => self.history.len() - 1,
            Some(_) => return,
        };
        self.history_idx = Some(idx);
        self.buffer = self.history[idx].clone();
        self.cursor = self.buffer.len();
    }

    pub fn history_down(&mut self) {
        match self.history_idx {
            Some(i) if i < self.history.len() - 1 => {
                let idx = i + 1;
                self.history_idx = Some(idx);
                self.buffer = self.history[idx].clone();
                self.cursor = self.buffer.len();
            }
            Some(_) => {
                self.history_idx = None;
                self.buffer.clear();
                self.cursor = 0;
            }
            None => {}
        }
    }

    pub fn clear(&mut self) {
        self.buffer.clear();
        self.cursor = 0;
        self.history_idx = None;
    }
}

#[derive(Debug, Clone)]
pub struct MiscState {
    pub overlay: Overlay,
    pub toasts: Vec<super::types::Toast>,
    pub dirty: bool,
    pub yolo_armed: bool,
    pub security_armed: bool,
    pub security_acknowledged: bool,
    pub esc_press_count: u32,
    pub last_staleness_sweep_ms: i64,
    pub effort_level: usize,
    pub editor: Option<crate::app::mode::editor::EditorState>,
}

impl MiscState {
    pub fn new() -> Self {
        MiscState {
            overlay: Overlay::None,
            toasts: Vec::new(),
            dirty: true,
            yolo_armed: false,
            security_armed: false,
            security_acknowledged: false,
            esc_press_count: 0,
            last_staleness_sweep_ms: 0,
            effort_level: 1,
            editor: None,
        }
    }

    pub fn push_toast(&mut self, toast: super::types::Toast) {
        self.toasts.push(toast);
    }

    pub fn drain_expired_toasts(&mut self, now_ms: i64) -> Vec<super::types::Toast> {
        let expired: Vec<_> = self.toasts.iter().filter(|t| t.expired(now_ms)).cloned().collect();
        self.toasts.retain(|t| !t.expired(now_ms));
        expired
    }
}