package main

import (
	. "dnmshared"
	"fmt"
	"github.com/hajimehoshi/ebiten/v2"
	"github.com/solarlune/resolv"
	"go.uber.org/zap"
	"image/color"

	"math"
)

type WorldColliderDisplay struct {
	Game  *Game
	Space *resolv.Space
}

func (world *WorldColliderDisplay) Init() {
}

func NewWorldColliderDisplay(game *Game, stageDiscreteW, stageDiscreteH, stageTileW, stageTileH int32, playerPosMap StrToVec2DListMap, barrierMap StrToPolygon2DListMap) *WorldColliderDisplay {

	playerList := *(playerPosMap["PlayerStartingPos"])
	barrierList := *(barrierMap["Barrier"])

	world := &WorldColliderDisplay{Game: game}

	Logger.Info("Parsed variables", zap.Any("stageDiscreteW", stageDiscreteW), zap.Any("stageDiscreteH", stageDiscreteH), zap.Any("stageTileW", stageTileW), zap.Any("stageTileH", stageTileH))

	spaceW := stageDiscreteW * stageTileW
	spaceH := stageDiscreteH * stageTileH

	spaceOffsetX := float64(spaceW) * 0.5
	spaceOffsetY := float64(spaceH) * 0.5

	// TODO: Move collider y-axis transformation to a "dnmshared"
	playerColliderRadius := float64(32)
    playerColliders := make([]*resolv.Object, len(playerList))
	space := resolv.NewSpace(int(spaceW), int(spaceH), 16, 16)
	for i, player := range playerList {
		playerCollider := resolv.NewObject(player.X-playerColliderRadius+spaceOffsetX, player.Y-playerColliderRadius+spaceOffsetY, playerColliderRadius*2, playerColliderRadius*2, "Player")
		playerColliderShape := resolv.NewRectangle(0, 0, playerColliderRadius*2, playerColliderRadius*2) // [WARNING] Deliberately not using a circle because "resolv v0.5.1" doesn't yet align circle center with space cell center, regardless of the "specified within-object offset" 
		playerCollider.SetShape(playerColliderShape)
        Logger.Info(fmt.Sprintf("Player Collider#%d: player.X=%v, player.Y=%v, radius=%v, spaceOffsetX=%v, spaceOffsetY=%v, shape=%v; calibrationCheckX=player.X-radius+spaceOffsetX=%v", i, player.X, player.Y, playerColliderRadius, spaceOffsetX, spaceOffsetY, playerCollider.Shape, player.X-playerColliderRadius+spaceOffsetX))
        playerColliders[i] = playerCollider
		space.Add(playerCollider)
	}

	barrierLocalId := 0
	for _, barrierUnaligned := range barrierList {
        barrier := AlignPolygon2DToBoundingBox(barrierUnaligned)

		var w float64 = 0
		var h float64 = 0

		for i, pi := range barrier.Points {
			for j, pj := range barrier.Points {
				if i == j {
					continue
				}
				if math.Abs(pj.X-pi.X) > w {
					w = math.Abs(pj.X - pi.X)
				}
				if math.Abs(pj.Y-pi.Y) > h {
					h = math.Abs(pj.Y - pi.Y)
				}
			}
		}

		barrierColliderShape := resolv.NewConvexPolygon()
		for i := 0; i < len(barrier.Points); i++ {
			p := barrier.Points[i]
			barrierColliderShape.AddPoints(p.X, p.Y)
		}

		barrierCollider := resolv.NewObject(barrier.Anchor.X+spaceOffsetX, barrier.Anchor.Y+spaceOffsetY, w, h, "Barrier")
		barrierCollider.SetShape(barrierColliderShape)

		space.Add(barrierCollider)
        Logger.Info(fmt.Sprintf("Added barrier: shape=%v", barrierCollider.Shape))
		barrierLocalId++
	}

	world.Space = space

    toTestPlayerCollider := playerColliders[0] 
    oldDx := 0.0
    oldDy := 180.0
    if collision := toTestPlayerCollider.Check(oldDx, oldDy, "Barrier"); collision != nil {
        toCheckBarrier := collision.Objects[0].Shape
        if intersection := toTestPlayerCollider.Shape.Intersection(oldDx, oldDy, toCheckBarrier); nil != intersection {
            Logger.Info(fmt.Sprintf("Collided: shape=%v, oldDx=%v, oldDy=%v, intersection.MTV=%v", toTestPlayerCollider.Shape, oldDx, oldDy, intersection.MTV))
        } else {
            Logger.Info(fmt.Sprintf("Collided: shape=%v, oldDx=%v, oldDy=%v, toCheckBarrier=%v, no intersecting points", toTestPlayerCollider.Shape, oldDx, oldDy, toCheckBarrier))
        }  
    } else {
        Logger.Info(fmt.Sprintf("Collision Test: shape=%v, oldDx=%v, oldDy=%v, not colliding with any Barrier", toTestPlayerCollider.Shape, oldDx, oldDy))
    }

    toTestPlayerCollider.Update()

	return world
}

func (world *WorldColliderDisplay) Update() {

}

func (world *WorldColliderDisplay) Draw(screen *ebiten.Image) {

	for _, o := range world.Space.Objects() {
		if o.HasTags("Player") {
			drawColor := color.RGBA{0, 255, 0, 255}
			DrawPolygon(screen, o.Shape.(*resolv.ConvexPolygon), drawColor)
		} else {
			drawColor := color.RGBA{60, 60, 60, 255}
			DrawPolygon(screen, o.Shape.(*resolv.ConvexPolygon), drawColor)
		}
	}

	world.Game.DebugDraw(screen, world.Space)

	if world.Game.ShowHelpText {

		world.Game.DrawText(screen, 16, 16,
			"~ Collider Display test ~",
			"F1: Toggle Debug View",
			"F2: Show / Hide help text",
			"R: Restart world",
			fmt.Sprintf("%d FPS (frames per second)", int(ebiten.CurrentFPS())),
			fmt.Sprintf("%d TPS (ticks per second)", int(ebiten.CurrentTPS())),
		)

	}

}