//! Theme and colour palette.
//!
//! Two themes are provided — one for light terminal backgrounds
//! and one for dark — per NFR-7. The palette is intentionally
//! small for the walking skeleton; it grows as more views are
//! added. Contrast is chosen against the target background so
//! that foreground text meets WCAG-AA (NFR-5) on both variants.

use ratatui::style::Color;

#[derive(Debug, Clone, Copy, PartialEq, Eq)]
pub enum Background {
    Light,
    Dark,
}

#[derive(Debug, Clone)]
pub struct Theme {
    pub background: Background,
    pub bg: Color,
    pub fg: Color,
    pub muted: Color,
    pub border: Color,
    pub border_advanced: Color,
    pub mode_simple: Color,
    pub mode_advanced: Color,
    pub system: Color,
    pub error: Color,
}

impl Theme {
    #[must_use]
    pub const fn dark() -> Self {
        Self {
            background: Background::Dark,
            bg: Color::Rgb(0x18, 0x1B, 0x22),
            fg: Color::Rgb(0xE6, 0xE6, 0xE6),
            muted: Color::Rgb(0x8B, 0x90, 0x9A),
            border: Color::Rgb(0x4A, 0x52, 0x65),
            border_advanced: Color::Rgb(0xE0, 0x60, 0x60),
            mode_simple: Color::Rgb(0x6E, 0xC4, 0xFF),
            mode_advanced: Color::Rgb(0xFF, 0x9E, 0x6B),
            system: Color::Rgb(0x9F, 0xD8, 0x91),
            error: Color::Rgb(0xFF, 0x6B, 0x6B),
        }
    }

    #[must_use]
    pub const fn light() -> Self {
        Self {
            background: Background::Light,
            bg: Color::Rgb(0xFA, 0xFA, 0xF7),
            fg: Color::Rgb(0x1A, 0x1F, 0x2C),
            muted: Color::Rgb(0x60, 0x66, 0x73),
            border: Color::Rgb(0xB6, 0xBC, 0xC8),
            border_advanced: Color::Rgb(0xC2, 0x3A, 0x3A),
            mode_simple: Color::Rgb(0x21, 0x69, 0xC7),
            mode_advanced: Color::Rgb(0xB0, 0x4A, 0x12),
            system: Color::Rgb(0x2E, 0x7C, 0x3C),
            error: Color::Rgb(0xC0, 0x39, 0x2B),
        }
    }
}

impl Default for Theme {
    fn default() -> Self {
        Self::dark()
    }
}