package server

import (
	"math"
	"math/rand"

	v "bitbucket.org/hackerbots/vector"
)

// Obstacle is the implementation of the generic building type in the game.
type Obstacle struct {
	Bounds v.AABB2d `json:"bounds"`
	Hp     int      `json:"-"`
}

func (o Obstacle) distance_from_point(p v.Point2d) float64 {
	dist := math.MaxFloat32

	dist = math.Min(dist, float64(p.Sub(o.Bounds.A).Mag()))
	dist = math.Min(dist, float64(p.Sub(o.Bounds.B).Mag()))
	dist = math.Min(dist, float64(p.Sub(v.Point2d{X: o.Bounds.A.X, Y: o.Bounds.B.Y}).Mag()))
	dist = math.Min(dist, float64(p.Sub(v.Point2d{X: o.Bounds.B.X, Y: o.Bounds.A.Y}).Mag()))

	return dist
}

func (o Obstacle) minify() [4]int {
	out := [4]int{int(o.Bounds.A.X), int(o.Bounds.A.Y), int(o.Bounds.B.X), int(o.Bounds.B.Y)}
	return out
}

// MinifyObstacles is a function used to convert []osbstacles into more tightly
// packed [][4]int for smaller json payloads
func MinifyObstacles(o []Obstacle) [][4]int {
	out := [][4]int{}
	for i := range o {
		out = append(out, o[i].minify())
	}
	return out
}

// GenerateObstacles returns a slice of (count) obstacles within a region
// bounded by width, height.
func GenerateObstacles(count int, width, height float64) []Obstacle {
	out := []Obstacle{}
	for i := 0; i < count; i++ {
		x := rand.Float64() * (width - (width / 10))
		y := rand.Float64() * (height - (height / 10))
		w := rand.Float64() * (width / 10)
		h := rand.Float64() * (height / 10)
		out = append(
			out,
			Obstacle{
				Bounds: v.AABB2d{
					A: v.Point2d{X: x, Y: y},
					B: v.Point2d{X: 20 + x + w, Y: 20 + y + h},
				},
				Hp: 10000,
			})
	}
	return out
}