common-range-tools 1.0.0

use crate::{
    AnyIncDecCpCmp, DefaultValues, GetBeginEnd, GetBeginEndOption, IncDecCpCmp, MrsP,
    NumberIncDecCpCmp, RangeRelation, RiFactory, first_range_begin_end, last_range_begin_end,
    next_range_begin_end, previous_range_begin_end, range_bounds_to_values, range_relation,
};

use std::marker::PhantomData;
use std::mem;
use std::ops::RangeInclusive;
use std::ops::{Add, RangeBounds, Sub};

/// Core of the consolidation code.
pub mod consolidate;

/// The core [Iterator]+[DoubleEndedIterator] for finding range intersections.
pub struct OverlapIter<T, V, C: IncDecCpCmp<T, V>, R: GetBeginEnd<T>, F: GetBeginEndOption<T, R>> {
    src: Vec<R>,
    step: V,
    cmp: C,
    next: Option<R>,
    back: Option<R>,
    last_next: Option<R>,
    last_back: Option<R>,
    factory: F,
    _marker: PhantomData<T>,
}

impl<T, V, C: IncDecCpCmp<T, V>, R: GetBeginEnd<T>, F: GetBeginEndOption<T, R>>
    OverlapIter<T, V, C, R, F>
{
    /// Creates a new [OverlapIter] from the slice of R.
    pub fn new(src: Vec<R>, step: V, cmp: C, factory: F) -> Self {
        let next = factory.factory(first_range_begin_end(&src, &step, &cmp));
        let back = factory.factory(last_range_begin_end(&src, &step, &cmp));

        Self {
            src,
            step,
            cmp,
            next,
            back,
            last_next: None,
            last_back: None,
            factory,
            _marker: PhantomData,
        }
    }

    /// Tries to copy the src ref range via the internals.
    /// Returns None if it fails.
    pub fn copy_range<U: GetBeginEnd<T>>(&self, src: &U) -> Option<R> {
        let a = self.cmp.cp(src.get_begin());
        let z = self.cmp.cp(src.get_end());
        return self.factory.factory(Some((a, z)));
    }

    /// Returns a tuple of Option refs to the internal next and last_next ranges.
    pub fn ln(&self) -> (Option<&R>, Option<&R>) {
        let a;
        let b;
        match &self.next {
            Some(n) => a = Some(n),
            _ => a = None,
        }
        match &self.last_next {
            Some(n) => b = Some(n),
            _ => b = None,
        }

        return (a, b);
    }

    /// Returns a tuple of Option refs to the internal back and last_back ranges.
    pub fn lb(&self) -> (Option<&R>, Option<&R>) {
        let a;
        let b;
        match &self.back {
            Some(n) => a = Some(n),
            _ => a = None,
        }
        match &self.last_back {
            Some(n) => b = Some(n),
            _ => b = None,
        }

        return (a, b);
    }

    /// After calling [OverlapIter::update_column], call this method in place of [OverlapIter::next] to return the properly updated next value.
    /// Calling this method resets the curent state of [OverlapIter::next_back].
    pub fn recompute_next(&mut self) -> Option<R> {
        self.last_back = None;
        self.back = self
            .factory
            .factory(last_range_begin_end(&self.src, &self.step, &self.cmp));

        let last_next = mem::replace(&mut self.last_next, None);
        match last_next {
            Some(x) => self.next = self.try_next(&Some(x)),
            _ => return None,
        }

        return self.next();
    }

    /// After calling [OverlapIter::update_column], call this method in place of [OverlapIter::next_back] to return the properly updated back value.
    /// Calling this method resets the curent state of [OverlapIter::next].
    pub fn recompute_back(&mut self) -> Option<R> {
        self.last_next = None;
        self.next = self
            .factory
            .factory(first_range_begin_end(&self.src, &self.step, &self.cmp));
        let last_back = mem::replace(&mut self.last_back, None);
        match last_back {
            Some(x) => self.back = self.try_next_back(&Some(x)),
            _ => return None,
        }

        return self.next_back();
    }

    /// Updates the internal column to the new [GetBeginEnd] instance.
    /// Returns [Result::Err] if the range is invalid or if the index point does not exist.
    ///
    /// After calling this method the next call to  [OverlapIter::next] or [OverlapIter::next_back] will not function correctly.
    /// First call the respective [OverlapIter::recompute_next] or [OverlapIter::recompute_back],
    /// then proceed to call either [OverlapIter::next] or [OverlapIter::next_back] normally.
    pub fn update_column(&mut self, idx: usize, range: R) -> Result<(), &'static str> {
        if let Some(col) = self.src.get_mut(idx) {
            if self.cmp.is_invalid_set(range.get_begin(), range.get_end()) {
                return Err("Invalid Range");
            }
            *col = range;
            return Ok(());
        }
        return Err("No such Column");
    }

    /// Genrates a new next based on the src passed in.
    pub fn try_next(&self, src: &Option<R>) -> Option<R> {
        let mut next = None;
        if let Some(n) = src {
            match &self.back {
                Some(b) => match range_relation(n, b, &self.cmp) {
                    RangeRelation::Overlap(_) => {
                        if let Some(begin) = self.cmp.inc(n.get_end(), &self.step) {
                            next = self.factory.factory(next_range_begin_end(
                                &begin,
                                &[
                                    MrsP {
                                        r: b,
                                        _t: PhantomData,
                                    },
                                    MrsP {
                                        r: n,
                                        _t: PhantomData,
                                    },
                                ],
                                &self.step,
                                &self.cmp,
                            ));
                        }
                    }
                    RangeRelation::Before(_) => {
                        if let Some(begin) = self.cmp.inc(n.get_end(), &self.step) {
                            next = self.factory.factory(next_range_begin_end(
                                &begin, &self.src, &self.step, &self.cmp,
                            ));
                        }
                    }
                    _ => return None,
                },
                None => (),
            }
        }
        return next;
    }

    /// Genrates a new back based on the src passed in.
    pub fn try_next_back(&self, src: &Option<R>) -> Option<R> {
        let mut back = None;
        if let Some(b) = src
            && let Some(n) = &self.next
        {
            match range_relation(b, n, &self.cmp) {
                RangeRelation::Overlap(_) => {
                    if let Some(end) = self.cmp.dec(b.get_begin(), &self.step) {
                        back = self.factory.factory(previous_range_begin_end(
                            &end,
                            &[
                                MrsP {
                                    r: n,
                                    _t: PhantomData,
                                },
                                MrsP {
                                    r: b,
                                    _t: PhantomData,
                                },
                            ],
                            &self.step,
                            &self.cmp,
                        ));
                    }
                }
                RangeRelation::After(_) => {
                    if let Some(end) = self.cmp.dec(b.get_begin(), &self.step) {
                        back = self.factory.factory(previous_range_begin_end(
                            &end, &self.src, &self.step, &self.cmp,
                        ));
                    }
                }
                _ => return None,
            }
        }
        return back;
    }
}

impl<T, V, C: IncDecCpCmp<T, V>, R: GetBeginEnd<T>, F: GetBeginEndOption<T, R>> Iterator
    for OverlapIter<T, V, C, R, F>
{
    type Item = R;

    /// This is part of a [DoubleEndedIterator] calls to [OverlapIter::next] impact calls to [OverlapIter::next_back].
    /// ## Big O Notation
    /// Each call to self.next() is a time complexity of O(n*3)
    fn next(&mut self) -> Option<Self::Item> {
        let next = self.try_next(&self.next);
        if let Some(next) = &self.next {
            self.last_next = self.copy_range(next);
        }
        return mem::replace(&mut self.next, next);
    }
}

impl<T, V, C: IncDecCpCmp<T, V>, R: GetBeginEnd<T>, F: GetBeginEndOption<T, R>> DoubleEndedIterator
    for OverlapIter<T, V, C, R, F>
{
    /// This is part of a [DoubleEndedIterator] calls to [OverlapIter::next_back] impact calls to [OverlapIter::next].
    /// ## Big O Notation
    /// Each call to self.next_back() is a time complexity of O(n*3)
    fn next_back(&mut self) -> Option<Self::Item> {
        let back = self.try_next_back(&self.back);
        if let Some(back) = &self.back {
            self.last_back = self.copy_range(back);
        }
        return mem::replace(&mut self.back, back);
    }
}

/// This acts as a general [OverlapIter] factory.
///
/// *The self.add_* methods*:
///
/// The various add_* methods return the index of the column that was added and the generated instance of [GetBeginEnd].
/// The index can be used to update that column during the iteration process
/// of the returned [OverlapIter] object instance.
/// See [OverlapIter::update_column] for more details.
pub struct Intersector<T, V, C: IncDecCpCmp<T, V>, R, F> {
    list: Vec<R>,
    step: V,
    rebound: V,
    cmp: C,
    factory: F,
    _r: PhantomData<(T, R)>,
}

impl<T, V, C: IncDecCpCmp<T, V>, R: GetBeginEnd<T>, B: GetBeginEndOption<T, R>>
    Intersector<T, V, C, R, B>
{
    /// Constructs a new instance of [Intersector].
    pub fn new(list: Vec<R>, step: V, rebound: V, cmp: C, factory: B) -> Self {
        Self {
            list,
            step,
            rebound,
            cmp,
            factory,
            _r: PhantomData,
        }
    }
}

impl<T, V> Intersector<T, V, AnyIncDecCpCmp<T>, RangeInclusive<T>, RiFactory<T>>
where
    T: PartialOrd + Copy + Add<V, Output = T> + Sub<V, Output = T>,
    V: Copy,
{
    /// Creates a new [Intersector] instance that works with any data type.
    pub fn any(
        step: V,
        rebound: V,
        min: T,
        max: T,
    ) -> Intersector<T, V, AnyIncDecCpCmp<T>, RangeInclusive<T>, RiFactory<T>> {
        Self {
            list: Vec::new(),
            step,
            rebound,
            cmp: AnyIncDecCpCmp::new(min, max),
            factory: RiFactory::new(),
            _r: PhantomData,
        }
    }

    pub fn any_from(
        step: V,
        rebound: V,
        min: T,
        max: T,
        src: &[impl RangeBounds<T>],
    ) -> OverlapIter<T, V, AnyIncDecCpCmp<T>, RangeInclusive<T>, RiFactory<T>> {
        let mut i = Self::any(step, rebound, min, max);
        for r in src {
            i.add_range(r);
        }
        return i.into_iter();
    }
}

impl<T> Intersector<T, T, NumberIncDecCpCmp<T>, RangeInclusive<T>, RiFactory<T>>
where
    T: PartialOrd + Copy + Add<T, Output = T> + Sub<T, Output = T>,
    NumberIncDecCpCmp<T>: DefaultValues<T, T>,
{
    /// Returns a new instance of [Intersector] configured to work with any primitive number type using the default values.
    pub fn num_defaults() -> Self {
        let cmp = NumberIncDecCpCmp::defaults();
        return Self {
            list: Vec::new(),
            step: cmp.default_step(),
            rebound: cmp.default_rebound(),
            cmp,
            factory: RiFactory::new(),
            _r: PhantomData,
        };
    }

    /// Returns a new instance of [Intersector] configured to work with numbers based on the arguments passed in.
    pub fn num(step: T, rebound: T, min: T, max: T) -> Self {
        return Self {
            list: Vec::new(),
            step,
            rebound,
            cmp: NumberIncDecCpCmp::new(min, max),
            factory: RiFactory::new(),
            _r: PhantomData,
        };
    }

    /// Returns a new instance of [Intersector] configured to work with numbers.
    /// The nteral step and rebound values are set to sr.
    pub fn num_sr(sr: T) -> Self {
        return Self {
            list: Vec::new(),
            step: sr,
            rebound: sr,
            cmp: NumberIncDecCpCmp::defaults(),
            factory: RiFactory::new(),
            _r: PhantomData,
        };
    }

    /// Takes any list of range of numbers and converts them to an instance of [OverlapIter].
    pub fn num_from(
        src: &[impl RangeBounds<T>],
    ) -> OverlapIter<T, T, NumberIncDecCpCmp<T>, RangeInclusive<T>, RiFactory<T>> {
        let mut i = Self::num_defaults();
        for r in src {
            i.add_range(r);
        }
        return i.into_iter();
    }

    /// Takes any list of range of numbers and converts them to an instance of [OverlapIter], with the step and rebound value set to sr.
    pub fn num_sr_from(
        sr: T,
        src: &[impl RangeBounds<T>],
    ) -> OverlapIter<T, T, NumberIncDecCpCmp<T>, RangeInclusive<T>, RiFactory<T>> {
        let mut i = Self::num_sr(sr);
        for r in src {
            i.add_range(r);
        }
        return i.into_iter();
    }
}

macro_rules! impl_intersector_num_core{
    ($($t:ty),*) => {
        $(
            impl Intersector<$t, $t, NumberIncDecCpCmp<$t>, RangeInclusive<$t>,RiFactory<$t>>
            where NumberIncDecCpCmp<$t>: DefaultValues<$t,$t> {}

        )*
    };
}
impl_intersector_num_core!(
    i8, i16, i32, i64, i128, isize, u8, u16, u32, u64, u128, usize, f32, f64
);

impl<T, V, C: IncDecCpCmp<T, V>, R: GetBeginEnd<T>, F: GetBeginEndOption<T, R>>
    Intersector<T, V, C, R, F>
{
    /// Tries to add an instance of [GetBeginEnd] to this instance returns None if src is invalid.
    pub fn add_raw_range(&mut self, src: R) -> Option<(usize, &R)> {
        if self.cmp.is_invalid_set(&src.get_begin(), &src.get_end()) {
            return None;
        }
        self.list.push(src);
        let id = self.list.len() - 1;
        return Some((id, &self.list[id]));
    }

    /// Tries to create and add a valid internal range from the tuple of refs.
    pub fn add_from_tuple_ref(&mut self, src: (&T, &T)) -> Option<(usize, &R)> {
        let a = self.cmp.cp(src.0);
        let z = self.cmp.cp(src.1);
        return self.add_from_tuple((a, z));
    }
    /// Tries to add a tuple to the instance, returns None if it fails.
    pub fn add_from_tuple(&mut self, src: (T, T)) -> Option<(usize, &R)> {
        match self.factory.factory(Some(src)) {
            Some(mrs) => return self.add_raw_range(mrs),
            None => None,
        }
    }

    /// This is really a wrapper for [crate::range_bounds_to_values].
    pub fn rebound(&self, r: &impl RangeBounds<T>) -> Option<(T, T)> {
        return range_bounds_to_values(r, self.get_rebound(), self.get_cmp());
    }

    /// Tries to convert a given [RangeBounds] instance to the internal range type.
    /// Returns None if the conversion process fails or the range produced is invalid.
    pub fn add_range(&mut self, r: &impl RangeBounds<T>) -> Option<(usize, &R)> {
        match self.rebound(r) {
            Some(src) => self.add_tuple(src),
            None => None,
        }
    }

    /// Tries to convert a tuple to the internal range type and add it.
    /// Returns None if the conversion process fails or the resulting range is invalid.
    pub fn add_tuple(&mut self, src: (T, T)) -> Option<(usize, &R)> {
        return self.add_from_tuple(src);
    }

    /// Returns a mutable ref to the internal instance of [IncDecCpCmp].
    pub fn get_cmp_mut(&mut self) -> &mut C {
        return &mut self.cmp;
    }

    /// Returns a ref to the internal instance of [IncDecCpCmp].
    pub fn get_cmp(&self) -> &C {
        return &self.cmp;
    }

    /// Returns a ref to the internal rebound value.
    pub fn get_rebound(&self) -> &V {
        return &self.rebound;
    }

    /// Returns a ref to the internal step value.
    pub fn get_step(&self) -> &V {
        return &self.step;
    }

    /// Updates the internal rebound value.
    pub fn set_rebound(&mut self, rebound: V) {
        self.rebound = rebound;
    }

    /// Updates the internal step value.
    pub fn set_step(&mut self, step: V) {
        self.step = step;
    }
}

impl<T, V, C: IncDecCpCmp<T, V>, R: GetBeginEnd<T>, F: GetBeginEndOption<T, R>> IntoIterator
    for Intersector<T, V, C, R, F>
{
    type Item = R;

    type IntoIter = OverlapIter<T, V, C, R, F>;

    /// Converts the current instance of [Intersector] into an instance of [OverlapIter].
    fn into_iter(self) -> Self::IntoIter {
        return OverlapIter::new(self.list, self.step, self.cmp, self.factory);
    }
}