use std::fmt::Debug;

use femtovg::Color;
use image::imageops::ColorMap;
use num_traits::{AsPrimitive, FromPrimitive, NumOps};

type BoundaryNormDiscrete<T> = ColorMapper<T, Discrete, BoundaryNorm<T>>;
macro_rules! color_mapper_comb {
    ($comb: ident, $($key: tt,)+) => {

        impl<T: PartialEq + PartialOrd + Debug> $comb<T> {

            pub fn color(&self, value: T) -> Option<femtovg::Color> {
                match self {
                    $(
                        Self::$key(mapper) => mapper.color(value),
                    )+
                }

            }
        }

    };
}

pub enum ColorMapperComb<T: PartialEq + PartialOrd + Debug> {
    BoundaryNormDiscrete(BoundaryNormDiscrete<T>),
}

color_mapper_comb!(ColorMapperComb, BoundaryNormDiscrete,);

pub trait VMap {
    type Ty;
    fn map(&self, v: Self::Ty) -> Option<f32>;
}

pub trait CMap {
    fn map(&self, v: f32) -> femtovg::Color;
}

pub struct ColorMapper<T, CMAP, VMAP>
where
    CMAP: CMap,
    VMAP: VMap<Ty = T>,
{
    cmap: CMAP,
    vmap: VMAP,
}

impl<T, CMAP, VMAP> ColorMapper<T, CMAP, VMAP>
where
    T: PartialEq + PartialOrd,
    CMAP: CMap,
    VMAP: VMap<Ty = T>,
{
    pub fn new(cmap: CMAP, vmap: VMAP) -> Self {
        Self { cmap, vmap }
    }

    pub fn color(&self, value: T) -> Option<femtovg::Color> {
        self.vmap.map(value).map(|v| self.cmap.map(v))
    }
}

#[derive(Debug)]
pub struct BoundaryNorm<T: PartialOrd + PartialEq> {
    boundaries: Vec<T>,
    extrand: bool,
    invalid_value: Option<T>,
}

impl<T: PartialEq + PartialOrd> BoundaryNorm<T> {
    pub fn new(boundaries: Vec<T>, extrand: bool, invalid_value: Option<T>) -> Self {
        Self {
            boundaries,
            extrand,
            invalid_value,
        }
    }
}

impl<T> VMap for BoundaryNorm<T>
where
    T: PartialOrd + PartialEq + Debug,
{
    type Ty = T;
    fn map(&self, v: Self::Ty) -> Option<f32> {
        let mut index = 0;
        if let Some(invalid_value) = &self.invalid_value {
            if v == *invalid_value {
                return None;
            }
        }

        for (i, boundary) in self.boundaries.iter().enumerate() {
            if v < *boundary {
                break;
            }
            index = i;
        }

        Some(index as f32 / self.boundaries.len() as f32)
    }
}

#[derive(Debug)]
pub struct Gradient {}

#[derive(Debug)]
pub struct Discrete {
    colors: Vec<femtovg::Color>,
}

impl Discrete {
    pub fn new(colors: Vec<femtovg::Color>) -> Self {
        Self { colors }
    }
}

impl CMap for Discrete {
    fn map(&self, v: f32) -> Color {
        let size = (self.colors.len() as f32 * v) as usize;
        self.colors.get(size).unwrap().clone()
    }
}

// #[derive(Debug, Clone)]
// pub struct BoundaryNorm<T: NumOps + PartialOrd> {
//     boundaries: Vec<T>,
//     extrand: bool,
//     colors: Vec<femtovg::Color>,
//     invalid_value: T,
// }
//
// impl Default for BoundaryNorm<i8> {
//     fn default() -> Self {
//         Self {
//             boundaries: vec![0, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65],
//             extrand: true,
//             colors: vec![
//                 Color::rgb(0, 172, 164),
//                 Color::rgb(192, 192, 254),
//                 Color::rgb(122, 114, 238),
//                 Color::rgb(30, 38, 208),
//                 Color::rgb(166, 252, 168),
//                 Color::rgb(0, 234, 0),
//                 Color::rgb(16, 146, 26),
//                 Color::rgb(252, 244, 100),
//                 Color::rgb(200, 200, 2),
//                 Color::rgb(140, 140, 0),
//                 Color::rgb(254, 172, 172),
//                 Color::rgb(254, 100, 92),
//                 Color::rgb(238, 2, 48),
//                 Color::rgb(212, 142, 254),
//                 Color::rgb(170, 36, 250),
//             ],
//             invalid_value: -125,
//         }
//     }
// }
//
// impl<T: NumOps + PartialOrd> BoundaryNorm<T> {
//     pub fn new(
//         boundaries: Vec<T>,
//         colors: Vec<femtovg::Color>,
//         extrand: bool,
//         invalid_value: T,
//     ) -> Self {
//         // assert_eq!(boundaries.len(), colors.len() + 1);
//         BoundaryNorm {
//             boundaries,
//             extrand,
//             colors,
//             invalid_value,
//         }
//     }
//
//     pub fn map_value_to_color(&self, value: f64, invalid_value: f64) -> Option<femtovg::Color> {
//         let mut index = 0;
//         if value == invalid_value {
//             return None;
//         }
//         for (i, boundary) in self.boundaries.iter().enumerate() {
//             if value < *boundary {
//                 break;
//             }
//             index = i;
//         }
//         index = index.saturating_sub(1).min(self.colors.len() - 1);
//         Some(self.colors[index])
//     }
// }
//
// impl<T> ColorMapper for BoundaryNorm<T>
// where
//     T: NumOps + PartialOrd + FromPrimitive + AsPrimitive<f64> + Send + Sync + Debug,
// {
//
//     type Ty<V> = T;
//     fn map_value_to_color<T>(&self, value: Self::Ty<T>, invalid_value: Self::Ty<T>) -> Option<femtovg::Color> {
//         self.map_value_to_color(value, invalid_value)
//     }
//
//     fn min_max(&self) -> (f64, f64) {
//         (
//             self.boundaries.first().unwrap().clone().as_(),
//             self.boundaries.last().unwrap().clone().as_(),
//         )
//     }
//
//     fn invalid(&self) -> f64 {
//         self.invalid_value.clone().as_()
//     }
//
//     fn map_min_to_max(&self) -> Vec<femtovg::Color> {
//         self.boundaries
//             .iter()
//             .map(|x| self.map_value_to_color(*x, self.invalid_value).unwrap())
//             .collect()
//     }
// }

// pub struct BoundaryNorm();
//
// impl ColorMapper for BoundaryNorm {
//     type Ty<T> = T;
//     fn map_value_to_color<T>(&self, value: Self::Ty<T>, invalid: T) -> Option<femtovg::Color> {
//         let mut index = 0;
//         if value == invalid_value {
//             return None;
//         }
//         for (i, boundary) in self.boundaries.iter().enumerate() {
//             if value < *boundary {
//                 break;
//             }
//             index = i;
//         }
//         index = index.saturating_sub(1).min(self.colors.len() - 1);
//         Some(self.colors[index])
//     }
//
//     fn map_min_to_max(&self) -> Vec<femtovg::Color> {
//         vec![]
//     }
//
//     fn min_max(&self) -> (f64, f64) {
//         (0.0, 0.0)
//     }
//
//     fn invalid(&self) -> f64 {
//         0.0
//     }
// }