#include "PathfindingContext.h"
#include "XY.h"
#include "Museum.h"
#include "NullTileBehavior.h"
#include "ToggleMuseumPauseCommand.h"

#include "DijkstraPathfinder.h"
#include "BreadthFirstPathfinder.h"

using namespace std;

PathfindingContext::PathfindingContext(Museum & m) : museum(m) {
  // this->solvers.push_back(unique_ptr<Pathfinder>(new DijkstraPathfinder(m)));
  this->solvers.push_back(unique_ptr<Pathfinder>(new BreadthFirstPathfinder(m)));
}

void PathfindingContext::cycle_solver() {
  this->solver_index = (this->solver_index + 1) % this->solvers.size();
}

Pathfinder & PathfindingContext::get_solver() {
  return *this->solvers[this->solver_index];
}

void PathfindingContext::set_start(const XY & point) {
  if (!this->valid_point(point)) return;
	this->start_point = point;
  this->update();
}

void PathfindingContext::set_end(const XY & point) {
  if (!this->valid_point(point)) return;
	this->end_point = point;
  this->update();
}

bool PathfindingContext::valid_point(const XY & point) {
	try {
		// check if square is empty (has null behavior)
		Tile & tile = this->museum.canvas.get_tile(point);
		TileBehavior * behavior = tile.behavior.get();
		if (dynamic_cast<NullTileBehavior *>(behavior) != nullptr) return false;
	} catch (...) {
		// get_tile throws an exception if the point is outside the canvas bounds
		return false;
	}

	return true;
}

void PathfindingContext::update() {
  bool valid = true;
  if (!this->valid_point(this->start_point)) {
    this->start_point = { -1, -1 };
    valid = false;
  }
  if (!this->valid_point(this->end_point)) {
    this->end_point = { -1, -1 };
    valid = false;
  }
  if (!valid) return;

  ToggleMuseumPauseCommand(this->museum, true).execute();
  Pathfinder & solver = this->get_solver();
  solver.find_between(this->start_point, this->end_point);
}