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use crate::components::Color;
use palette::*;
use palette::luma::Luma;
use palette::rgb::Rgb;

const PHI: f32 = 1.61803398 * 1.3;

/// Function to convert pixel values into rem (factor of browser's default font size)
pub fn sp(value: i32) -> String {
    let real_value = value as f32;
    format!("{}rem", real_value / 16.0)
}

/// Helper to get harmonious spacing and sizing values.
/// It's based on `scale ^ PHI` calculation
pub fn scale(scale: i32) -> i32 {
    let real_scale = scale as f32;
    real_scale.powf(PHI).ceil() as i32
}

/// Helper to get most visible text color based on a background color
/// Return black if luminance is less than 50% and white otherwise
pub fn contrast_color(color_hex: &String) -> String {
    let color = Color::from_alpha_hex(&color_hex);
    let lcolor: SrgbLuma  =  Srgba::new(
        color.0 as f32 / 255.0,
        color.1 as f32 / 255.0,
        color.2 as f32 / 255.0,
        color.3 as f32 / 255.0
    ).into_color();
    if lcolor.luma > 0.5 {
        "#000000".to_string()
    } else {
        "#ffffff".to_string()
    }
}

/// Helper to get most visible text color based on a background color
/// Return black if luminance is less than 50% and white otherwise
pub fn harden_color(color_hex: &String) -> String {
    let color = Color::from_alpha_hex(&color_hex);
    let alpha = color.3 as f32 / 255.0;
    let new_color = LinSrgb::new(
        color.0 as f32 / 255.0,
        color.1 as f32 / 255.0,
        color.2 as f32 / 255.0,
    )
        .mix(&LinSrgb::new(1.0, 1.0, 1.0), 1.0 - alpha);
    format!("#{:02x?}{:02x?}{:02x?}", (new_color.red * 255.0) as u8, (new_color.green * 255.0) as u8, (new_color.blue * 255.0) as u8)
}