Input Methods

Input    Output    Explanation
───────────────────────────────
aaa      âa        aa → â, third 'a' stays
ass      as        as → á, second 's' removes sắc
aww      aw        aw → ă, second 'w' removes breve
oww      ow        ow → ơ, second 'w' removes horn

pub struct Telex;

impl Method for Telex {
    fn mark(&self, key: u16) -> Option<u8> {
        match key {
            keys::S => Some(1), // sắc
            keys::F => Some(2), // huyền
            keys::R => Some(3), // hỏi
            keys::X => Some(4), // ngã
            keys::J => Some(5), // nặng
            _ => None,
        }
    }

    fn tone(&self, key: u16) -> Option<ToneType> {
        match key {
            keys::A | keys::E | keys::O => Some(ToneType::Circumflex),
            keys::W => Some(ToneType::Horn),
            _ => None,
        }
    }

    fn stroke(&self, key: u16) -> bool {
        key == keys::D
    }

    fn remove(&self, key: u16) -> bool {
        key == keys::Z
    }
}

pub struct Vni;

impl Method for Vni {
    fn mark(&self, key: u16) -> Option<u8> {
        match key {
            keys::N1 => Some(1), // sắc
            keys::N2 => Some(2), // huyền
            keys::N3 => Some(3), // hỏi
            keys::N4 => Some(4), // ngã
            keys::N5 => Some(5), // nặng
            _ => None,
        }
    }

    fn tone(&self, key: u16) -> Option<ToneType> {
        match key {
            keys::N6 => Some(ToneType::Circumflex),
            keys::N7 => Some(ToneType::Horn),
            keys::N8 => Some(ToneType::Breve),
            _ => None,
        }
    }

    fn stroke(&self, key: u16) -> bool {
        key == keys::N9
    }

    fn remove(&self, key: u16) -> bool {
        key == keys::N0
    }
}

bá, bà, bả, bã, bạ

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