#[cfg(test)]
#[path = "../../../tests/unit/construction/heuristics/evaluators_test.rs"]
mod evaluators_test;
use std::sync::Arc;
use crate::construction::heuristics::*;
use crate::models::common::Cost;
use crate::models::problem::{Job, Multi, Single};
use crate::models::solution::{Activity, Leg, Place};
use crate::models::{ConstraintViolation, GoalContext};
use crate::utils::Either;
use rosomaxa::utils::unwrap_from_result;
pub struct EvaluationContext<'a> {
pub goal: &'a GoalContext,
pub job: &'a Job,
pub leg_selection: &'a LegSelection,
pub result_selector: &'a (dyn ResultSelector + Send + Sync),
}
#[derive(Copy, Clone)]
pub enum InsertionPosition {
Any,
Concrete(usize),
Last,
}
pub fn eval_job_insertion_in_route(
insertion_ctx: &InsertionContext,
eval_ctx: &EvaluationContext,
route_ctx: &RouteContext,
position: InsertionPosition,
alternative: InsertionResult,
) -> InsertionResult {
match (route_ctx.is_stale(), insertion_ctx.solution.unassigned.get(eval_ctx.job)) {
(false, Some(UnassignmentInfo::Simple(_))) | (false, Some(UnassignmentInfo::Detailed(_))) => {
return alternative
}
_ => {}
}
let goal = &insertion_ctx.problem.goal;
if let Some(violation) = goal.evaluate(&MoveContext::route(&insertion_ctx.solution, route_ctx, eval_ctx.job)) {
return eval_ctx.result_selector.select_insertion(
insertion_ctx,
alternative,
InsertionResult::make_failure_with_code(violation.code, true, Some(eval_ctx.job.clone())),
);
}
let route_costs = goal.estimate(&MoveContext::route(&insertion_ctx.solution, route_ctx, eval_ctx.job));
let best_known_cost = match &alternative {
InsertionResult::Success(success) => Some(success.cost),
_ => None,
};
if let Some(best_known_cost) = best_known_cost {
if let Either::Left(_) = eval_ctx.result_selector.select_cost(route_ctx, best_known_cost, route_costs) {
return alternative;
}
}
eval_ctx.result_selector.select_insertion(
insertion_ctx,
alternative,
eval_job_constraint_in_route(eval_ctx, route_ctx, position, route_costs, best_known_cost),
)
}
pub fn eval_job_constraint_in_route(
eval_ctx: &EvaluationContext,
route_ctx: &RouteContext,
position: InsertionPosition,
route_costs: Cost,
best_known_cost: Option<Cost>,
) -> InsertionResult {
match eval_ctx.job {
Job::Single(single) => eval_single(eval_ctx, route_ctx, single, position, route_costs, best_known_cost),
Job::Multi(multi) => eval_multi(eval_ctx, route_ctx, multi, position, route_costs, best_known_cost),
}
}
pub(crate) fn eval_single_constraint_in_route(
insertion_ctx: &InsertionContext,
eval_ctx: &EvaluationContext,
route_ctx: &RouteContext,
single: &Arc<Single>,
position: InsertionPosition,
route_costs: Cost,
best_known_cost: Option<Cost>,
) -> InsertionResult {
if let Some(violation) =
eval_ctx.goal.evaluate(&MoveContext::route(&insertion_ctx.solution, route_ctx, eval_ctx.job))
{
InsertionResult::Failure(InsertionFailure {
constraint: violation.code,
stopped: true,
job: Some(eval_ctx.job.clone()),
})
} else {
eval_single(eval_ctx, route_ctx, single, position, route_costs, best_known_cost)
}
}
fn eval_single(
eval_ctx: &EvaluationContext,
route_ctx: &RouteContext,
single: &Arc<Single>,
position: InsertionPosition,
route_costs: Cost,
best_known_cost: Option<Cost>,
) -> InsertionResult {
let insertion_idx = get_insertion_index(route_ctx, position);
let mut activity = Activity::new_with_job(single.clone());
let result = analyze_insertion_in_route(
eval_ctx,
route_ctx,
insertion_idx,
single,
&mut activity,
route_costs,
SingleContext::new(best_known_cost, 0),
);
let job = eval_ctx.job.clone();
if result.is_success() {
activity.place = result.place.unwrap();
let activities = vec![(activity, result.index)];
InsertionResult::make_success(result.cost.unwrap(), job, activities, route_ctx.clone())
} else {
let (code, stopped) = result.violation.map_or((0, false), |v| (v.code, v.stopped));
InsertionResult::make_failure_with_code(code, stopped, Some(job))
}
}
fn eval_multi(
eval_ctx: &EvaluationContext,
route_ctx: &RouteContext,
multi: &Arc<Multi>,
position: InsertionPosition,
route_costs: Cost,
best_known_cost: Option<Cost>,
) -> InsertionResult {
let insertion_idx = get_insertion_index(route_ctx, position).unwrap_or(0);
let result = unwrap_from_result(multi.permutations().into_iter().try_fold(
MultiContext::new(best_known_cost, insertion_idx),
|acc_res, services| {
let mut shadow = ShadowContext::new(eval_ctx.goal, route_ctx);
let perm_res = unwrap_from_result((0..).try_fold(MultiContext::new(None, insertion_idx), |out, _| {
if out.is_failure(route_ctx.route.tour.job_activity_count()) {
return Err(out);
}
shadow.restore(route_ctx);
let sq_res = unwrap_from_result(services.iter().try_fold(out.next(), |in1, service| {
if in1.violation.is_some() {
return Err(in1);
}
let mut activity = Activity::new_with_job(service.clone());
let srv_res = analyze_insertion_in_route(
eval_ctx,
&shadow.ctx,
None,
service,
&mut activity,
0.,
SingleContext::new(None, in1.next_index),
);
if srv_res.is_success() {
activity.place = srv_res.place.unwrap();
let activity = shadow.insert(activity, srv_res.index);
let activities = concat_activities(in1.activities, (activity, srv_res.index));
return MultiContext::success(
in1.cost.unwrap_or(route_costs) + srv_res.cost.unwrap(),
activities,
);
}
MultiContext::fail(srv_res, in1)
}));
MultiContext::promote(sq_res, out)
}));
MultiContext::promote(perm_res, acc_res)
},
));
let job = eval_ctx.job.clone();
if result.is_success() {
let activities = result.activities.unwrap();
InsertionResult::make_success(result.cost.unwrap(), job, activities, route_ctx.clone())
} else {
let (code, stopped) = result.violation.map_or((0, false), |v| (v.code, v.stopped));
InsertionResult::make_failure_with_code(code, stopped, Some(job))
}
}
fn analyze_insertion_in_route(
eval_ctx: &EvaluationContext,
route_ctx: &RouteContext,
insertion_idx: Option<usize>,
single: &Single,
target: &mut Activity,
route_costs: Cost,
init: SingleContext,
) -> SingleContext {
let mut analyze_leg_insertion = |leg: Leg<'_>, init| {
analyze_insertion_in_route_leg(eval_ctx, route_ctx, leg, single, target, route_costs, init)
};
match insertion_idx {
Some(idx) => {
if let Some(leg) = route_ctx.route.tour.legs().nth(idx) {
unwrap_from_result(analyze_leg_insertion(leg, init))
} else {
init
}
}
None => eval_ctx.leg_selection.sample_best(
route_ctx,
eval_ctx.job,
init.index,
init,
&mut |leg: Leg<'_>, init| analyze_leg_insertion(leg, init),
|lhs: &SingleContext, rhs: &SingleContext| {
eval_ctx
.result_selector
.select_cost(route_ctx, lhs.cost.unwrap_or(f64::MAX), rhs.cost.unwrap_or(f64::MAX))
.is_left()
},
),
}
}
fn analyze_insertion_in_route_leg(
eval_ctx: &EvaluationContext,
route_ctx: &RouteContext,
leg: Leg,
single: &Single,
target: &mut Activity,
route_costs: Cost,
init: SingleContext,
) -> Result<SingleContext, SingleContext> {
let (items, index) = leg;
let (prev, next) = match items {
[prev] => (prev, None),
[prev, next] => (prev, Some(next)),
_ => panic!("Unexpected route leg configuration."),
};
let start_time = route_ctx.route.tour.start().unwrap().schedule.departure;
single.places.iter().try_fold(init, |acc, detail| {
detail.times.iter().try_fold(acc, |acc, time| {
target.place = Place {
location: detail.location.unwrap_or(prev.place.location),
duration: detail.duration,
time: time.to_time_window(start_time),
};
let activity_ctx = ActivityContext { index, prev, target, next };
if let Some(violation) = eval_ctx.goal.evaluate(&MoveContext::activity(route_ctx, &activity_ctx)) {
return SingleContext::fail(violation, acc);
}
let costs = eval_ctx.goal.estimate(&MoveContext::activity(route_ctx, &activity_ctx)) + route_costs;
let other_costs = acc.cost.unwrap_or(f64::MAX);
match eval_ctx.result_selector.select_cost(route_ctx, costs, other_costs) {
Either::Left(_) => SingleContext::success(activity_ctx.index, costs, target.place.clone()),
Either::Right(_) => SingleContext::skip(acc),
}
})
})
}
fn get_insertion_index(route_ctx: &RouteContext, position: InsertionPosition) -> Option<usize> {
match position {
InsertionPosition::Any => None,
InsertionPosition::Concrete(idx) => Some(idx),
InsertionPosition::Last => Some(route_ctx.route.tour.legs().count().max(1) - 1),
}
}
#[derive(Clone, Debug, Default)]
struct SingleContext {
pub violation: Option<ConstraintViolation>,
pub index: usize,
pub cost: Option<Cost>,
pub place: Option<Place>,
}
impl SingleContext {
fn new(cost: Option<Cost>, index: usize) -> Self {
Self { violation: None, index, cost, place: None }
}
fn fail(violation: ConstraintViolation, other: SingleContext) -> Result<Self, Self> {
let stopped = violation.stopped;
let ctx = Self { violation: Some(violation), index: other.index, cost: other.cost, place: other.place };
if stopped {
Err(ctx)
} else {
Ok(ctx)
}
}
#[allow(clippy::unnecessary_wraps)]
fn success(index: usize, cost: Cost, place: Place) -> Result<Self, Self> {
Ok(Self { violation: None, index, cost: Some(cost), place: Some(place) })
}
#[allow(clippy::unnecessary_wraps)]
fn skip(other: SingleContext) -> Result<Self, Self> {
Ok(other)
}
fn is_success(&self) -> bool {
self.place.is_some()
}
}
struct MultiContext {
pub violation: Option<ConstraintViolation>,
pub start_index: usize,
pub next_index: usize,
pub cost: Option<Cost>,
pub activities: Option<Vec<(Activity, usize)>>,
}
impl MultiContext {
fn new(cost: Option<Cost>, index: usize) -> Self {
Self { violation: None, start_index: index, next_index: index, cost, activities: None }
}
fn promote(left: Self, right: Self) -> Result<Self, Self> {
let index = left.start_index.max(right.start_index) + 1;
let best = match (left.cost, right.cost) {
(Some(left_cost), Some(right_cost)) => {
if left_cost < right_cost {
left
} else {
right
}
}
(Some(_), None) => left,
(None, Some(_)) => right,
(None, None) => {
if left.violation.is_some() {
left
} else {
right
}
}
};
let result = Self {
violation: best.violation,
start_index: index,
next_index: index,
cost: best.cost,
activities: best.activities,
};
if result.violation.as_ref().map_or(false, |v| v.stopped) {
Err(result)
} else {
Ok(result)
}
}
fn fail(err_ctx: SingleContext, other_ctx: MultiContext) -> Result<Self, Self> {
let (code, stopped) =
err_ctx.violation.map_or((0, false), |v| (v.code, v.stopped && other_ctx.activities.is_none()));
Err(Self {
violation: Some(ConstraintViolation { code, stopped }),
start_index: other_ctx.start_index,
next_index: other_ctx.start_index,
cost: None,
activities: None,
})
}
#[allow(clippy::unnecessary_wraps)]
fn success(cost: Cost, activities: Vec<(Activity, usize)>) -> Result<Self, Self> {
Ok(Self {
violation: None,
start_index: activities.first().unwrap().1,
next_index: activities.last().unwrap().1 + 1,
cost: Some(cost),
activities: Some(activities),
})
}
fn next(&self) -> Self {
Self {
violation: None,
start_index: self.start_index,
next_index: self.start_index,
cost: None,
activities: None,
}
}
fn is_success(&self) -> bool {
self.violation.is_none() && self.cost.is_some() && self.activities.is_some()
}
fn is_failure(&self, index: usize) -> bool {
self.violation.as_ref().map_or(false, |v| v.stopped) || (self.start_index > index)
}
}
struct ShadowContext<'a> {
is_mutated: bool,
is_dirty: bool,
goal: &'a GoalContext,
ctx: RouteContext,
}
impl<'a> ShadowContext<'a> {
fn new(goal: &'a GoalContext, ctx: &RouteContext) -> Self {
Self { is_mutated: false, is_dirty: false, goal, ctx: ctx.clone() }
}
fn insert(&mut self, activity: Activity, index: usize) -> Activity {
if !self.is_mutated {
self.ctx = self.ctx.deep_copy();
self.is_mutated = true;
}
self.ctx.route_mut().tour.insert_at(activity.deep_copy(), index + 1);
self.goal.accept_route_state(&mut self.ctx);
self.is_dirty = true;
activity
}
fn restore(&mut self, original: &RouteContext) {
if self.is_dirty {
self.ctx = original.clone();
self.is_mutated = false;
self.is_dirty = false;
}
}
}
fn concat_activities(
activities: Option<Vec<(Activity, usize)>>,
activity: (Activity, usize),
) -> Vec<(Activity, usize)> {
let mut activities = activities.unwrap_or_default();
activities.push((activity.0, activity.1));
activities
}