use core::{cell::RefCell, char, marker::PhantomData};

use alloc::vec;
use alloc::{
    boxed::Box,
    collections::{btree_map::BTreeMap, btree_set::BTreeSet},
    rc::Rc,
    string::{String, ToString},
    vec::Vec,
};
use critical_section::Mutex;

use crate::at_commands::{ATCommand, ATError, ATResponseParser, SimpleATCommand};

#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
pub enum KeypadButton {
    Keypad1,
    Keypad2,
    Keypad3,
    Keypad4,
    Keypad5,
    Keypad6,
    Keypad7,
    Keypad8,
    Keypad9,
    Keypad0,
    KeypadStar,
    KeypadHash,
    KeypadA,
    KeypadB,
    KeypadC,
    KeypadD,
}

#[derive(Clone)]
pub struct Keypad {
    was_pressed: Rc<Mutex<RefCell<BTreeSet<KeypadButton>>>>,
    is_pressed: Rc<Mutex<RefCell<BTreeSet<KeypadButton>>>>,
    presses: Rc<Mutex<RefCell<BTreeMap<KeypadButton, u32>>>>,
}

impl Default for Keypad {
    fn default() -> Self {
        Self {
            was_pressed: Rc::new(Mutex::new(RefCell::new(Default::default()))),
            is_pressed: Rc::new(Mutex::new(RefCell::new(Default::default()))),
            presses: Rc::new(Mutex::new(RefCell::new(Default::default()))),
        }
    }
}

impl Keypad {
    pub fn handle_presses(&self, presses: BTreeSet<KeypadButton>) {
        critical_section::with(|cs| {
            let mut was_pressed = self.was_pressed.borrow_ref_mut(cs);
            let mut is_pressed = self.is_pressed.borrow_ref_mut(cs);
            let mut num_presses = self.presses.borrow_ref(cs).clone();

            *was_pressed = is_pressed.clone();
            *is_pressed = presses;
            for button in is_pressed.iter() {
                if !was_pressed.contains(button) {
                    let num = num_presses.get(button).copied().unwrap_or(0);
                    log::info!("{:?}", *button);
                    num_presses.insert(*button, num + 1);
                }
            }

            *self.presses.borrow_ref_mut(cs) = num_presses;
        });
    }

    pub fn get_presses(&self, button: KeypadButton) -> u32 {
        critical_section::with(|cs| {
            let presses = self.presses.borrow_ref(cs);
            presses.get(&button).copied().unwrap_or(0)
        })
    }

    pub fn is_pressed(&self, button: KeypadButton) -> bool {
        critical_section::with(|cs| {
            let is_pressed = self.is_pressed.borrow_ref(cs);
            is_pressed.contains(&button)
        })
    }

    pub fn pressed_buttons(&self) -> BTreeSet<KeypadButton> {
        critical_section::with(|cs| {
            let is_pressed = self.is_pressed.borrow_ref(cs);
            is_pressed.clone()
        })
    }

    pub fn just_pressed_buttons(&self) -> BTreeSet<KeypadButton> {
        critical_section::with(|cs| {
            let presses = self.presses.borrow_ref(cs);
            presses.keys().copied().collect()
        })
    }

    pub fn clear(&self) {
        critical_section::with(|cs| {
            let mut presses = self.presses.borrow_ref_mut(cs);
            presses.clear();
        })
    }
}

#[derive(Clone)]
pub struct AsyncIO {
    at_command: Rc<Mutex<RefCell<Option<Box<dyn SimpleATCommand>>>>>,
    handling_at_command: Rc<Mutex<RefCell<bool>>>,
    at_response: Rc<Mutex<RefCell<Option<Result<Vec<String>, ATError>>>>>,
    pub keypad: Keypad,
}

impl Default for AsyncIO {
    fn default() -> Self {
        Self {
            at_command: Rc::new(Mutex::new(RefCell::new(None))),
            handling_at_command: Rc::new(Mutex::new(RefCell::new(false))),
            at_response: Rc::new(Mutex::new(RefCell::new(None))),
            keypad: Keypad::default(),
        }
    }
}

unsafe impl Send for AsyncIO {}
unsafe impl Sync for AsyncIO {}

#[derive(Default, Clone, Debug)]
pub struct ATPromise<T: ATCommand> {
    _data: PhantomData<T>,
}

impl<T: ATCommand> ATPromise<T> {
    pub fn poll(&self, io: &mut AsyncIO) -> Option<Result<T::Response, ATError>> {
        match io.poll_at_response() {
            Some(response) => {
                log::info!("Response: {:?}", response);
                match response {
                    Ok(response) => {
                        let mut parser = ATResponseParser::from(response);
                        Some(T::parse_response(&mut parser))
                    }
                    Err(err) => Some(Err(err)),
                }
            }
            None => None,
        }
    }
}

impl AsyncIO {
    pub fn send_at_command<Resp, T: ATCommand<Response = Resp> + 'static>(
        &self,
        command: T,
    ) -> Result<ATPromise<T>, ()> {
        critical_section::with(|cs| {
            let mut borrow = self.at_command.borrow_ref_mut(cs);
            if borrow.is_some() {
                return Err(());
            }

            *borrow = Some(Box::new(command));

            Ok(ATPromise { _data: PhantomData })
        })
    }

    pub unsafe fn check_at_command(self) -> Option<Box<dyn SimpleATCommand>> {
        critical_section::with(|cs| {
            let mut borrow = self.at_command.borrow_ref_mut(cs);
            *self.handling_at_command.borrow_ref_mut(cs) = true;
            borrow.take()
        })
    }

    pub unsafe fn set_at_response(&self, response_str: Result<Vec<String>, ATError>) {
        critical_section::with(|cs| {
            *self.handling_at_command.borrow_ref_mut(cs) = false;
            let mut command = self.at_command.borrow_ref_mut(cs);
            let mut response = self.at_response.borrow_ref_mut(cs);
            command.take();
            *response = Some(response_str);
        })
    }

    fn poll_at_response(&self) -> Option<Result<Vec<String>, ATError>> {
        critical_section::with(|cs| {
            let command = self.at_command.borrow_ref(cs);
            let mut response = self.at_response.borrow_ref_mut(cs);
            if command.is_some() {
                return None;
            }
            if let Some(resp) = response.take() {
                return Some(resp);
            }
            None
        })
    }
}

#[derive(Default, Clone)]
pub struct NumberInput {
    written: String,
}

impl NumberInput {
    pub fn poll(&mut self, io: &mut AsyncIO) -> bool {
        let mut wrote = false;
        for button in io.keypad.just_pressed_buttons() {
            let character = match button {
                KeypadButton::Keypad1 => Some('1'),
                KeypadButton::Keypad2 => Some('2'),
                KeypadButton::Keypad3 => Some('3'),
                KeypadButton::Keypad4 => Some('4'),
                KeypadButton::Keypad5 => Some('5'),
                KeypadButton::Keypad6 => Some('6'),
                KeypadButton::Keypad7 => Some('7'),
                KeypadButton::Keypad8 => Some('8'),
                KeypadButton::Keypad9 => Some('9'),
                KeypadButton::Keypad0 => Some('0'),
                _ => None,
            };
            if let Some(character) = character {
                self.written += &character.to_string();
                wrote = true;
            }
        }
        wrote
    }

    pub fn read<'s>(&'s self) -> &'s String {
        &self.written
    }
}

impl KeypadButton {
    pub fn get_chars(&self) -> Option<Vec<char>> {
        match self {
            KeypadButton::Keypad1 => Some(vec![' ', '1']),
            KeypadButton::Keypad2 => Some(vec!['a', 'b', 'c', '2']),
            KeypadButton::Keypad3 => Some(vec!['d', 'e', 'f', '3']),
            KeypadButton::Keypad4 => Some(vec!['g', 'h', 'i', '4']),
            KeypadButton::Keypad5 => Some(vec!['j', 'k', 'l', '5']),
            KeypadButton::Keypad6 => Some(vec!['m', 'n', 'o', '6']),
            KeypadButton::Keypad7 => Some(vec!['p', 'q', 'r', 's', '7']),
            KeypadButton::Keypad8 => Some(vec!['t', 'u', 'v', '8']),
            KeypadButton::Keypad9 => Some(vec!['w', 'x', 'y', 'z', '9']),
            KeypadButton::Keypad0 => Some(vec![' ', '0']),
            KeypadButton::KeypadStar => Some(vec!['*']),
            KeypadButton::KeypadHash => Some(vec!['#']),
            _ => None,
        }
    }
}

#[derive(Debug, Clone)]
pub struct LastPressed {
    key: KeypadButton,
    idx: usize,
}

impl LastPressed {
    pub fn increment(&mut self) {
        let chars = self.key.get_chars();
        if let Some(chars) = chars {
            self.idx = (self.idx + 1) % chars.len()
        }
    }

    pub fn get_char(&self) -> char {
        self.key.get_chars().unwrap()[self.idx]
    }
}

static TEXT_KEYS: [KeypadButton; 13] = [
    KeypadButton::Keypad0,
    KeypadButton::Keypad1,
    KeypadButton::Keypad2,
    KeypadButton::Keypad3,
    KeypadButton::Keypad4,
    KeypadButton::Keypad5,
    KeypadButton::Keypad6,
    KeypadButton::Keypad7,
    KeypadButton::Keypad8,
    KeypadButton::Keypad9,
    KeypadButton::Keypad0,
    KeypadButton::KeypadStar,
    KeypadButton::KeypadHash,
];

#[derive(Debug, Default, Clone)]
pub struct TextInput {
    written: String,
    last_pressed: Option<LastPressed>,
}

impl TextInput {
    pub fn poll(&mut self, io: &mut AsyncIO) -> bool {
        let mut wrote = false;
        for button in io.keypad.just_pressed_buttons() {
            if let Some(mut last_pressed) = self.last_pressed.take() {
                if last_pressed.key == button {
                    last_pressed.increment();
                    self.last_pressed = Some(last_pressed);
                    wrote = true;
                } else if TEXT_KEYS.contains(&button) {
                    self.written += &last_pressed.get_char().to_string();
                    self.last_pressed = Some(LastPressed {
                        key: button,
                        idx: 0,
                    });
                    wrote = true;
                } else if button == KeypadButton::KeypadA {
                    self.written += &last_pressed.get_char().to_string();
                    wrote = true;
                }
            } else if TEXT_KEYS.contains(&button) {
                self.last_pressed = Some(LastPressed {
                    key: button,
                    idx: 0,
                });
                wrote = true;
            }
        }
        wrote
    }

    pub fn read(&self) -> String {
        let mut written = self.written.clone();
        if let Some(last_pressed) = &self.last_pressed {
            written += &last_pressed.get_char().to_string();
        }
        written
    }
}