/*
Copyright 2016 Martin Buck

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"),
to deal in the Software without restriction, including without limitation the
rights to use, copy, modify, merge, publish, distribute, sublicense,
and/or sell copies of the Software, and to permit persons to whom the Software
is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall
be included all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE
OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/

//! utility functions

use std::cmp::Ordering;

use prelude::*;

//@todo move these functions to better fitting files or make them methods of the correct types

/// Returns the center of two IsBuildable2D
pub fn center_2d<P>(p1: &P, p2: &P) -> P where
    P: IsBuildable2D {

    P::new(
        p1.x() + (p2.x() - p1.x()) / 2.0,
        p1.y() + (p2.y() - p1.y()) / 2.0
    )
}

/// Returns the center of two IsBuildable3D
pub fn center_3d<P>(p1: &P, p2: &P) -> P where
    P: IsBuildable3D {

    P::new(
        p1.x() + (p2.x() - p1.x()) / 2.0,
        p1.y() + (p2.y() - p1.y()) / 2.0,
        p1.z() + (p2.z() - p1.z()) / 2.0
    )
}

/// Returns the cross product between a Is3D and a IsBuildable3D
pub fn cross<P,U>(first: &P, other: &U) -> U where
    P: Is3D,
    U: IsBuildable3D {

    let x = first.y() * other.z() - first.z() * other.y();
    let y = first.z() * other.x() - first.x() * other.z();
    let z = first.x() * other.y() - first.y() * other.x();
    U::new(x, y, z)
}

/// Compares two IsBuildable3D at a given dimensions
pub fn dimension_compare<P1, P2>(lhs: &P1, rhs: &P2, dim: i8) -> Result<Ordering> where
    P1: Is3D,
    P2: Is3D {

    match dim {
        0 => lhs.x().partial_cmp(&rhs.x()).ok_or(ErrorKind::ComparisionFailed),
        1 => lhs.y().partial_cmp(&rhs.y()).ok_or(ErrorKind::ComparisionFailed),
        2 => lhs.z().partial_cmp(&rhs.z()).ok_or(ErrorKind::ComparisionFailed),
        _ => Err(ErrorKind::DimensionsDontMatch)
    }
}

/// Calculates the distance within a given dimension between two IsBuildable3D
pub fn dimension_dist<P1, P2>(lhs: &P1, rhs: &P2, dim: i8) -> Result<f64> where
    P1: Is3D,
    P2: Is3D {

    match dim {
        0 => Ok((lhs.x() - rhs.x()).abs()),
        1 => Ok((lhs.y() - rhs.y()).abs()),
        2 => Ok((lhs.z() - rhs.z()).abs()),
        _ => Err(ErrorKind::DimensionsDontMatch)
    }
}

/// Helper function to sort a Vec of Is2D by x
pub fn sort_vec_2d_x<P>(xs: &mut Vec<P>) where
    P: Is2D {

        xs.sort_by(|a, b|
            a.x().partial_cmp(&b.x())
                .or_else(|| a.y().partial_cmp(&b.y()))
                .unwrap_or(Ordering::Equal));
}

/// Helper function to sort a Vec of Is2D by y
pub fn sort_vec_2d_y<P>(xs: &mut Vec<P>) where
    P: Is2D {

        xs.sort_by(|a, b|
            a.y().partial_cmp(&b.y())
                .or_else(|| a.x().partial_cmp(&b.x()))
                .unwrap_or(Ordering::Equal));
}

/// Helper function to sort a Vec of Is3D by x
pub fn sort_vec_3d_x<P>(xs: &mut Vec<P>) where
    P: Is3D {

        xs.sort_by(|a, b|
            a.x().partial_cmp(&b.x())
                .or_else(|| a.y().partial_cmp(&b.y()))
                .or_else(|| a.z().partial_cmp(&b.z()))
                .unwrap_or(Ordering::Equal));
}

/// Helper function to sort a Vec of Is3D by y
pub fn sort_vec_3d_y<P>(xs: &mut Vec<P>) where
    P: Is3D {

        xs.sort_by(|a, b|
            a.y().partial_cmp(&b.y())
                .or_else(|| a.z().partial_cmp(&b.z()))
                .or_else(|| a.x().partial_cmp(&b.x()))
                .unwrap_or(Ordering::Equal));
}

/// Helper function to sort a Vec of Is3D by z
pub fn sort_vec_3d_z<P>(xs: &mut Vec<P>) where
    P: Is3D {

        xs.sort_by(|a, b|
            a.z().partial_cmp(&b.z())
                .or_else(|| a.x().partial_cmp(&b.x()))
                .or_else(|| a.y().partial_cmp(&b.y()))
                .unwrap_or(Ordering::Equal));
}

//@todo move to plane or use there
/// Extrudes a 2D point cloud into 3D space with a given center and direction
pub fn extrude<P2,P3>(pc2d: &Vec<P2>, dir: &P3) -> (PointCloud3D<P3>, PointCloud3D<P3>) where
    P2: IsTransFormableTo3D,
    P3: IsBuildable3D + IsMovable3D + Clone {

    let mut pc_3d_a = PointCloud3D::new();
    let mut pc_3d_b = PointCloud3D::new();

    for p in pc2d {
        let p_transformed = p.transform_to_3d::<P3>(0.0);
        pc_3d_a.push(p_transformed.clone());
        pc_3d_b.push(p_transformed);
    }

    pc_3d_b.move_by(dir.x(), dir.y(), dir.z());
    (pc_3d_a, pc_3d_b)
}

//@todo rename or overload operators
//@todo implement for 2D as well, maybe move to traits
/// Calculates the vector between two positions
pub fn conn<P>(p_from: &P, p_to: &P) -> P where
    P: IsBuildable3D {

    P::new(
        p_to.x() - p_from.x(),
        p_to.y() - p_from.y(),
        p_to.z() - p_from.z()
    )
}

/// Projects a point onto a plane
pub fn project_point_on_plane<PL,P2,P3,N>(plane: &PL, point: &P3) -> P2 where
    PL: IsPlane3D<P3,N>,
    P2: IsBuildable2D,
    P3: IsBuildable3D + IsTransFormableTo2D,
    N:  IsNormalized3D {

    let relative = conn(&plane.origin(), point);
    let mut p2transf = point.transform_to_2d::<P2>();
    let mut tmp = Point2D::default();

    tmp.set_x(plane.u().dot(&relative));
    tmp.set_y(plane.v().dot(&relative));

    p2transf.from(tmp);
    p2transf
}