-- Note: Any mods which define the collision box size of prototypes in data-final-fixes.lua will not be affected by this code if that mod loads after this one.
--       Prototypes normally defined in data.lua, or data-updates.lua will be loaded before this executes and properly updated.

-- Table of prototype types to check and the minimum gap required to allow walking in between them. 
local prototype_type_gap_requirements = {
	["solar-panel"]             = 0.25,
	["accumulator"]             = 0.25,
	["generator"]               = 0.25,
	["pipe"]                    = 0.42,
	["pipe-to-ground"]          = 0.42,
	["container"]               = 0.25,
	["smart-container"]         = 0.25,
	["logistic-container"]      = 0.25,
	["assembling-machine"]      = 0.25,
	["arithmetic-combinator"]   = 0.25,
	["decider-combinator"]      = 0.25,
	["constant-combinator"]     = 0.25,
	["boiler"]                  = 0.42,
	["electric-pole"]           = 0.25,
	["mining-drill"]            = 0.25,
	["pump"]                    = 0.42,
	["radar"]                   = 0.25,
	["storage-tank"]            = 0.25,
	["tree"]                    = 0.25,
	["turret"]                  = 0.25,
	["beacon"]                  = 0.25,
	["furnace"]                 = 0.25,
	["lab"]                     = 0.25,
	}
-- All defined prototypes of the types listed above will be checked in adjust_collision_boxes() and have their collision boxes reduced to form the specified gap where needed.


-- Returns a coordinate reduced where required to form the specified gap between it and the tile boundary.
local function adjust_coordinate_to_form_gap(coordinate, required_gap)

	-- Treat all coordinates as positive to simplify calculations.
	local is_negative_coordinate = (coordinate < 0)
	if is_negative_coordinate then
		coordinate = coordinate * -1
	end
	
	local tile_width = 0.5
	
	-- Calculate the existing gap (how much space there is to the next tile edge or 0 when the coordinate lies on a tile edge).
	local distance_past_last_tile_edge = coordinate % tile_width -- This is how far the collision box extends over any tile edge, and should be 0 for a perfect fit.
	local existing_gap = 0
	if distance_past_last_tile_edge > 0 then
		existing_gap = (tile_width - distance_past_last_tile_edge)
	end
	
	-- Reduce the coordinate to make the gap large enough if it is not already.
	if existing_gap < required_gap then
		coordinate = coordinate + existing_gap - required_gap
	end
	
	-- Make the coordinate negative again if it was originally negative.
	if is_negative_coordinate then
		coordinate = coordinate * -1
	end
	
	return coordinate
end


-- Checks all existing prototypes listed in prototype_type_gap_requirements and reduces their collision box to make a gap large enough to walk though if it is not already.
local function adjust_collision_boxes()
	
	for prototype_type, required_gap in pairs(prototype_type_gap_requirements) do
	
		for key, prototype in pairs(data.raw[prototype_type]) do
		
			-- If the prototype has a collision box then resize it.
			if prototype["collision_box"] then
				
				for y=1,2 do
					for x=1,2 do
						prototype.collision_box[x][y] = adjust_coordinate_to_form_gap(prototype.collision_box[x][y], required_gap)
					end
				end
				
			end
			
		end
	end
end


-- Make the adjustments.
adjust_collision_boxes()