const.TunnelTypeWalk = 2^0
const.TunnelTypeStairs = 2^1
const.TunnelTypeLadder = 2^2
const.TunnelTypeDrop1 = 2^3
const.TunnelTypeDrop2 = 2^4
const.TunnelTypeDrop3 = 2^5
const.TunnelTypeDrop4 = 2^6
const.TunnelTypeClimb1 = 2^7
const.TunnelTypeClimb2 = 2^8
const.TunnelTypeClimb3 = 2^9
const.TunnelTypeClimb4 = 2^10
const.TunnelTypeJumpOver1 = 2^11
const.TunnelTypeJumpOver2 = 2^12
const.TunnelTypeJumpAcross1 = 2^13
const.TunnelTypeJumpAcross2 = 2^14
const.TunnelTypeDoor = 2^15
const.TunnelTypeDoorBlocked = 2^16
const.TunnelTypeWindow = 2^17

const.TunnelMaskWalkFlat = const.TunnelTypeWalk
const.TunnelMaskWalk = const.TunnelTypeWalk | const.TunnelTypeStairs
const.TunnelMaskClimb = const.TunnelTypeClimb1 | const.TunnelTypeClimb2 | const.TunnelTypeClimb3 | const.TunnelTypeClimb4
const.TunnelMaskDrop = const.TunnelTypeDrop1 | const.TunnelTypeDrop2 | const.TunnelTypeDrop3 | const.TunnelTypeDrop4
const.TunnelMaskClimbDrop = const.TunnelMaskClimb| const.TunnelMaskDrop
const.TunnelMaskSmallAnimals = const.TunnelMaskWalk | const.TunnelTypeClimb1 | const.TunnelTypeClimb2 | const.TunnelTypeDrop1 | const.TunnelTypeDrop2
const.TunnelMaskLargeAnimals = const.TunnelMaskWalk
const.TunnelMaskPlayerStanding = -1
const.TunnelMaskPlayerProne = const.TunnelTypeWalk
const.TunnelMaskAIStanding = const.TunnelMaskPlayerStanding & ~const.TunnelTypeDoorBlocked
const.TunnelMaskAIProne = const.TunnelMaskPlayerProne & ~const.TunnelTypeDoorBlocked
const.TunnelMaskCivilian = const.TunnelMaskPlayerStanding & ~(const.TunnelTypeDoorBlocked | const.TunnelTypeWindow | const.TunnelMaskClimbDrop)
	| const.TunnelTypeDrop1 | const.TunnelTypeClimb1
const.TunnelMaskMeleeRange = const.TunnelMaskWalk | const.TunnelTypeClimb1 | const.TunnelTypeDrop1 | const.TunnelTypeJumpOver1
const.TunnelMaskClosedDoor = const.TunnelTypeDoor | const.TunnelTypeDoorBlocked

const.TunnelMaskTraverseWait =
	const.TunnelTypeLadder |
	const.TunnelTypeDrop2 |
	const.TunnelTypeDrop3 |
	const.TunnelTypeDrop4 |
	const.TunnelTypeClimb1 |
	const.TunnelTypeClimb2 |
	const.TunnelTypeClimb3 |
	const.TunnelTypeClimb4 |
	const.TunnelTypeJumpOver1 |
	const.TunnelTypeJumpOver2 |
	const.TunnelTypeJumpAcross1 |
	const.TunnelTypeJumpAcross2 |
	const.TunnelTypeDoorBlocked |
	const.TunnelTypeWindow	

const.TunnelMaskWalkStopAnim = 
	const.TunnelTypeLadder |
	const.TunnelTypeDrop3 |
	const.TunnelTypeDrop4 |
	const.TunnelTypeClimb2 |
	const.TunnelTypeClimb3 |
	const.TunnelTypeClimb4 |
	const.TunnelTypeDoor |
	const.TunnelTypeDoorBlocked |
	const.TunnelTypeWindow

local costWalk = 500
local difficult_terrain_modifier = 50
local costDifficultTerrain = costWalk * (100 + difficult_terrain_modifier) / 100

if Platform.desktop and Platform.developer then
	function OnMsg.Autorun()
		-- update the constant depend on the preset
		assert(costWalk == Presets.ConstDef["Action Point Costs"].Walk.value * const.PassTileSize / const.SlabSizeX)
		assert(difficult_terrain_modifier == Presets.ConstDef["Action Point Costs"].DifficultTerrainModifier.value)
	end
end

pathfind_pass_types = {
	"DefaultPass",
	"DifficultTerrain",
	"AmbientLifeAvoid",
	"FireTerrain",
}
pathfind_pass_grid_types = {
	"DefaultPass",
	"AmbientLifeAvoid",
	"FireTerrain",
}
pathfind_water_pass_type = "DifficultTerrain"
pathfind_water_pass_type_idx = (table.find(pathfind_pass_types, pathfind_water_pass_type) or 0) - 1 -- zero based

local default_pfcontext_meta = { __index = {
	depth = 100000,
	min_depth = 100000,
	max_path_search_radius_coef = 100,
	heuristic_mul = 2 * 4, -- 2 bit fixed point
	heuristic_start_depth = 20000,
	task_sleep = 0,
	tunnel_mask = -1,
	-- pass type costs
	DefaultPass = costWalk,
	DifficultTerrain = costDifficultTerrain,
	AmbientLifeAvoid = costWalk,
	FireTerrain = costWalk * 3,
}}

pathfind = {
	{	-- player controlled unit standing or crouch stance
		tunnel_mask = const.TunnelMaskPlayerStanding,
	},
	{	-- player controlled unit prone stance
		tunnel_mask = const.TunnelMaskPlayerProne,
		DifficultTerrain = const.pfImpassableCost,
	},
	{	-- AI controlled unit standing or crouch stance
		tunnel_mask = const.TunnelMaskAIStanding,
	},
	{	-- AI controlled unit prone stance
		tunnel_mask = const.TunnelMaskAIProne,
		DifficultTerrain = const.pfImpassableCost,
	},
	{	-- ambient life
		tunnel_mask = const.TunnelMaskCivilian,
		AmbientLifeAvoid = 4 * costWalk,
		FireTerrain = 4 * costWalk,
	},
	{	-- small animals
		tunnel_mask = const.TunnelMaskSmallAnimals,
	},
	{	-- large animals
		tunnel_mask = const.TunnelMaskLargeAnimals,
		large_unit_pass_radius = 1,
		large_unit_collision_cost = 4 * costWalk,
	},
}
for i, t in ipairs(pathfind) do
	setmetatable(t, default_pfcontext_meta)
end

function CalcPFClass(side, stance, body_type)
	if body_type == "Large animal" then
		return 6
	elseif body_type == "Small animal" then
		return 5
	elseif not side or side == "neutral" then
		return 4
	elseif side ~= "player1" and side ~= "player2" then
		return stance == "Prone" and 3 or 2
	end
	return stance == "Prone" and 1 or 0
end

pathfind_surf_types = {}

const.MaxPassableTerrainSlope = atan(const.SlabSizeZ, const.SlabSizeX)
const.PathMaxUnitRadius = 6*guim
const.PathMaxZTolerance = 2*guim
const.PathStrandedArea = 0

const.MaxPassableWaterDepth = 0 -- when the water is marker impassable

-- Obstacle collision spheroid sizes (in cm units)
const.passSpheroidWidth = 60*guic
const.passSpheroidHeight = 165*guic
const.passSpheroidCollisionOffsetZ = 10*guic

const.passVoxelTileSpheroidWidth = 80*guic
const.passVoxelTileSpheroidHeight = 175*guic
const.passVoxelTileSpheroidCollisionOffsetZ = 10*guic

--const.PathTurnAnimBlendTime = 500
--const.PathTurnRadius = 3*guim       -- Defines the max arc radius for a 90 deg turn (in normal and large pass grids)
--const.PathTurnAnimRadius = 150*guic -- Defines the arc radius of the turning animation (the min "confortable" turn radius)
--const.PathTurnMinTime = 600