use crate::*;

/// The `Tui` struct (the *engine*) implements the
/// `tengri_input::Input` and `tengri_output::Out` traits.
/// At launch, the `Tui` engine spawns two threads, the render thread and the input thread.
/// the application may further spawn other threads. All threads communicate using shared ownership:
/// `Arc<RwLock<T>>` and `Arc<AtomicT>`. Thus, at launch the engine and application instances are expected to be wrapped in `Arc<RwLock>`.
pub struct Tui {
    pub exited:  Arc<AtomicBool>,
    pub backend: CrosstermBackend<Stdout>,
    pub buffer:  Buffer,
    pub area:    [u16;4],
    pub perf:    PerfModel,
}

#[derive(Debug, Clone)] pub struct TuiIn {
    /// Input event
    pub event:  TuiEvent,
    /// Exit flag
    pub exited: Arc<AtomicBool>,
}

#[derive(Debug, Clone, Eq, PartialEq, PartialOrd)] pub struct TuiEvent(pub Event);

#[derive(Debug, Clone, Eq, PartialEq, PartialOrd)] pub struct TuiKey(
    pub Option<KeyCode>,
    pub KeyModifiers
);

#[derive(Default)] pub struct TuiOut {
    pub buffer: Buffer,
    pub area:   XYWH<u16>,
}

/// TUI buffer sized by `usize` instead of `u16`.
#[derive(Default)] pub struct BigBuffer {
    pub width:   usize,
    pub height:  usize,
    pub content: Vec<Cell>
}

/// A color in OKHSL and RGB representations.
#[derive(Debug, Default, Copy, Clone, PartialEq)] pub struct ItemColor {
    pub okhsl: Okhsl<f32>,
    pub rgb:   Color,
}
/// A color in OKHSL and RGB with lighter and darker variants.
#[derive(Debug, Default, Copy, Clone, PartialEq)] pub struct ItemTheme {
    pub base:     ItemColor,
    pub light:    ItemColor,
    pub lighter:  ItemColor,
    pub lightest: ItemColor,
    pub dark:     ItemColor,
    pub darker:   ItemColor,
    pub darkest:  ItemColor,
}

pub struct Modify<T>(pub bool, pub Modifier, pub T);

pub struct Styled<T>(pub Option<Style>, pub T);

/// Displays an owned [str]-like with fixed maximum width.
///
/// Width is computed using [unicode_width].
pub struct TrimString<T: AsRef<str>>(pub u16, pub T);

/// Displays a borrowed [str]-like with fixed maximum width
///
/// Width is computed using [unicode_width].
pub struct TrimStringRef<'a, T: AsRef<str>>(pub u16, pub &'a T);

/// Thunks can be natural error boundaries!
pub struct ErrorBoundary<O: Out, T: Draw<O>>(
    pub std::marker::PhantomData<O>,
    pub Perhaps<T>
);

/// Repeat a string, e.g. for background
pub enum Repeat<'a> {
    X(&'a str),
    Y(&'a str),
    XY(&'a str)
}

/// Scroll indicator
pub enum Scrollbar {
    /// Horizontal scrollbar
    X { offset: usize, length: usize, total: usize, },
    /// Vertical scrollbar
    Y { offset: usize, length: usize, total: usize, }
}

/// A cell that takes up 3 rows on its own,
/// but stacks, giving (N+1)*2 rows per N cells.
pub struct Phat<T> {
    pub width:   u16,
    pub height:  u16,
    pub content: T,
    pub colors:  [Color;4],
}