1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172

use super::{cvt, get_optional, Alignment, Geometry};
use std::io;
use std::marker::PhantomData;

use libparted_sys::{
    ped_constraint_destroy, ped_constraint_done, ped_constraint_duplicate, ped_constraint_init,
    ped_constraint_intersect, ped_constraint_is_solution, ped_constraint_new,
    ped_constraint_new_from_max, ped_constraint_new_from_min, ped_constraint_new_from_min_max,
    ped_constraint_solve_max, ped_constraint_solve_nearest, PedConstraint,
};

pub(crate) enum ConstraintSource {
    Init,
    New,
}

pub struct Constraint<'a> {
    pub(crate) constraint: *mut PedConstraint,
    pub(crate) source: ConstraintSource,
    pub(crate) phantom: PhantomData<&'a PedConstraint>,
}

impl<'a> Constraint<'a> {
    fn new_(constraint: *mut PedConstraint, source: ConstraintSource) -> Constraint<'a> {
        Constraint {
            constraint,
            source,
            phantom: PhantomData,
        }
    }

    /// A convenience wrapper for `Constraint::init()`.
    ///
    /// Allocates a new piece of memory and initializes the constraint.
    pub fn new(
        start_align: &Alignment,
        end_align: &Alignment,
        start_range: &Geometry,
        end_range: &Geometry,
        min_size: i64,
        max_size: i64,
    ) -> io::Result<Constraint<'a>> {
        cvt(unsafe {
            ped_constraint_new(
                start_align.alignment,
                end_align.alignment,
                start_range.geometry,
                end_range.geometry,
                min_size,
                max_size,
            )
        })
        .map(|constraint| Constraint::new_(constraint, ConstraintSource::New))
    }

    /// Return a constraint that requires a region to be entirely contained inside `max`.
    pub fn new_from_max(max: &Geometry) -> io::Result<Constraint<'a>> {
        cvt(unsafe { ped_constraint_new_from_max(max.geometry) })
            .map(|constraint| Constraint::new_(constraint, ConstraintSource::New))
    }

    /// Return a constraint that requires a region to be entirely contained inside `min`.
    pub fn new_from_min(min: &Geometry) -> io::Result<Constraint<'a>> {
        cvt(unsafe { ped_constraint_new_from_min(min.geometry) })
            .map(|constraint| Constraint::new_(constraint, ConstraintSource::New))
    }

    /// Return a constraint that requires a region to be entirely contained inside `min` and `max'.
    pub fn new_from_min_max(min: &Geometry, max: &Geometry) -> io::Result<Constraint<'a>> {
        cvt(unsafe { ped_constraint_new_from_min_max(min.geometry, max.geometry) })
            .map(|constraint| Constraint::new_(constraint, ConstraintSource::New))
    }

    /// Initializes a pre-allocated piece of memory to contain a constraint with the supplied
    /// default values.
    pub fn init(
        &mut self,
        start_align: &Alignment,
        end_align: &Alignment,
        start_range: &Geometry,
        end_range: &Geometry,
        min_size: i64,
        max_size: i64,
    ) -> io::Result<()> {
        cvt(unsafe {
            ped_constraint_init(
                self.constraint,
                start_align.alignment,
                end_align.alignment,
                start_range.geometry,
                end_range.geometry,
                min_size,
                max_size,
            )
        })?;

        self.source = ConstraintSource::Init;
        Ok(())
    }

    pub fn start_align(&self) -> Alignment {
        Alignment::from_raw(unsafe { (*self.constraint).start_align })
    }

    pub fn end_align(&self) -> Alignment {
        Alignment::from_raw(unsafe { (*self.constraint).end_align })
    }

    pub fn start_range(&self) -> Geometry {
        Geometry::from_raw(unsafe { (*self.constraint).start_range })
    }

    pub fn end_range(&self) -> Geometry {
        Geometry::from_raw(unsafe { (*self.constraint).end_range })
    }

    pub fn min_size(&'a self) -> i64 {
        unsafe { (*self.constraint).min_size }
    }

    pub fn max_size(&'a self) -> i64 {
        unsafe { (*self.constraint).max_size }
    }

    /// Duplicates a constraint, if possible.
    pub fn duplicate<'b>(&self) -> io::Result<Constraint<'b>> {
        cvt(unsafe { ped_constraint_duplicate(self.constraint) })
            .map(|constraint| Constraint::new_(constraint, ConstraintSource::New))
    }

    /// If the supplied constraint intersects with our constraint, a constraint will
    /// be returned with the computed solution.
    pub fn intersect(&self, other: &Constraint) -> Option<Constraint<'a>> {
        get_optional(unsafe { ped_constraint_intersect(self.constraint, other.constraint) })
            .map(|constraint| Constraint::new_(constraint, ConstraintSource::New))
    }

    /// Check whether `geometry` satisfies the constraint.
    pub fn is_solution(&self, geometry: &Geometry) -> bool {
        unsafe { ped_constraint_is_solution(self.constraint, geometry.geometry) == 1 }
    }

    /// Find the largest region that satisfies a constraint.Alignment
    ///
    /// There might be more than one solution. This function makes no guarantees about which
    /// solutions it will choose in this case.
    pub fn solve_max(&self) -> Option<Geometry<'a>> {
        get_optional(unsafe { ped_constraint_solve_max(self.constraint) }).map(Geometry::from_raw)
    }

    /// Return the nearest region to `geom` that satisfies the constraint.
    ///
    /// # Note:
    ///
    /// _Nearest_ is somewhat ambiguous. This function makes no guarantees
    /// about how this ambiguity is resolved.
    pub fn solve_nearest(&self, geom: &Geometry) -> Option<Geometry<'a>> {
        get_optional(unsafe { ped_constraint_solve_nearest(self.constraint, geom.geometry) })
            .map(Geometry::from_raw)
    }
}

impl<'a> Drop for Constraint<'a> {
    fn drop(&mut self) {
        unsafe {
            match self.source {
                ConstraintSource::Init => ped_constraint_done(self.constraint),
                ConstraintSource::New => ped_constraint_destroy(self.constraint),
            }
        }
    }
}