
local simplex_noise = require 'utils.simplex_noise'
local simplex_noise = simplex_noise.d2
local event = require 'utils.event'
local biter_battles_terrain = {}
local math_random = math.random
local table_insert = table.insert

local function on_chunk_generated(event)
	
	local seed = game.surfaces[1].map_gen_settings.seed
	
	if not game.surfaces["surface"] then return end
	
	local surface = game.surfaces["surface"]
	if event.surface.name ~= surface.name then return end
	
	local ore_amount = 2500
	local ores = {"copper-ore", "iron-ore", "stone", "coal"}
	local noise = {}
	--local tiles = {}	
	
	local aa = 0.0113
	local bb = 21
	local xx = 1.1
	local cc = xx - (aa * bb)
	
	for x = 0, 31, 1 do
		for y = 0, 31, 1 do
		--	tiles = {}	
			local pos_x = event.area.left_top.x + x
			local pos_y = event.area.left_top.y + y														
			local tile_to_insert = false
			local entity_has_been_placed = false		
			
			noise[1] = simplex_noise(pos_x/250, pos_y/250,seed)
			noise[2] = simplex_noise(pos_x/75, pos_y/75,seed+10000)	
			noise[8] = simplex_noise(pos_x/15, pos_y/15,seed+40000)					
			noise[3] = noise[1] + noise[2] * 0.2 + noise[8]*0.02
			
			noise[4] = simplex_noise(pos_x/200, pos_y/200,seed+15000)	
			noise[5] = simplex_noise(pos_x/20, pos_y/20,seed+20000)	
			noise[6] = simplex_noise(pos_x/8, pos_y/8,seed+25000)
			noise[7] = simplex_noise(pos_x/400, pos_y/400,seed+35000)			
			local water_noise = noise[4] + (noise[6] * 0.006) + (noise[5] * 0.04)
			
			local a = ore_amount * (1+(noise[2]*0.3))						
			xx = 1.1
			if noise[3] >= cc then
				for yy = 1, bb, 1 do
					local z = (yy % 4) + 1
					xx = xx - aa
					if noise[3] > xx then					
						if surface.can_place_entity {name=ores[z], position={pos_x,pos_y}, amount=a} then
							surface.create_entity {name=ores[z], position={pos_x,pos_y}, amount=a}
						end
						entity_has_been_placed = true
						break
					end				
				end
			end
			if entity_has_been_placed == false then
				if water_noise < -0.92 and water_noise < noise[7] then
					tile_to_insert = "water"					
				end
				if water_noise < -0.97 and water_noise < noise[7] then
					tile_to_insert = "deepwater"							
				end
			end
			--if tile_to_insert then table_insert(tiles, {name = tile_to_insert, position = {pos_x,pos_y}}) end
			if tile_to_insert then surface.set_tiles({{name = tile_to_insert, position = {pos_x,pos_y}}}, true) end
					
			if tile_to_insert == "water" or tile_to_insert == "deepwater" then
				if surface.can_place_entity{name="fish", position={pos_x,pos_y}} and math_random(1,14) == 1 then
					surface.create_entity {name="fish", position={pos_x,pos_y}} 
				end
			end
		end							
	end
		
	if event.area.left_top.y < 160 or event.area.left_top.y > -192 then	
		local tiles = {}		
		local spawn_tile = surface.get_tile(game.forces.south.get_spawn_position(surface))	
		local radius = 24  --starting pond radius
		local radsquare = radius*radius
		local horizontal_border_width = global.horizontal_border_width
		for x = 0, 31, 1 do
			for y = 0, 31, 1 do
				tiles = {}
				local pos_x = event.area.left_top.x + x
				local pos_y = event.area.left_top.y + y														
				local tile_to_insert = false				
				local tile_distance_to_center = pos_x^2 + pos_y^2
				noise[4] = simplex_noise(pos_x/85, pos_y/85,seed+20000)		
				noise[5] = simplex_noise(pos_x/7, pos_y/7,seed+30000)	
				noise[7] = 1 + (noise[4]+(noise[5]*0.75))*0.11						
				if pos_y >= ((horizontal_border_width/2)*-1)*noise[7] and pos_y <= (horizontal_border_width/2)*noise[7] then
					if pos_x < 20 and pos_x > -20 then
						local entities = surface.find_entities({{pos_x, pos_y}, {pos_x+1, pos_y+1}})						
						for _, e in pairs(entities) do
							if e.type == "simple-entity" or e.type == "resource" or e.type == "tree" then
								e.destroy()
							end
						end
					end
					tile_to_insert = "deepwater"
				else
					local t = surface.get_tile(pos_x,pos_y)
					if t.name == "deepwater" or t.name =="water" then					
						if tile_distance_to_center < 20000 then
							if spawn_tile.name == "water" or spawn_tile.name == "deepwater" then 
								tile_to_insert = "sand-1"
							else
								tile_to_insert = spawn_tile.name
							end
						end
					end
				end					
				if tile_distance_to_center <= radsquare then
						if tile_distance_to_center >= radsquare/10 then
							tile_to_insert = "deepwater"
						else
							tile_to_insert = "sand-1"
							if tile_distance_to_center >= radsquare/18 then
								tile_to_insert = "refined-concrete"
							end
						end
				end			
				if tile_to_insert then table_insert(tiles, {name = tile_to_insert, position = {pos_x,pos_y}}) end
				surface.set_tiles(tiles,true)
				
				if tile_to_insert == "deepwater" then
					if surface.can_place_entity{name="fish", position={pos_x,pos_y}} and math_random(1,35) == 1 then
						surface.create_entity {name="fish", position={pos_x,pos_y}} 
					end	
				end
			end
		end								
	end		
end

local function find_tile_placement_spot_around_target_position(tilename, position, mode, density)
	local x = position.x
	local y = position.y
	if not surface then surface = game.surfaces["surface"] end
	local scan_radius = 50
	if not tilename then return end
	if not mode then mode = "ball" end
	if not density then density = 1 end
	local cluster_tiles = {}
	local auto_correct = true
	
	local scanned_tile = surface.get_tile(x,y)
	if scanned_tile.name ~= tilename then
		table_insert(cluster_tiles, {name = tilename, position = {x,y}})
		surface.set_tiles(cluster_tiles,auto_correct)
		return true, x, y
	end
	
	local i = 2
	local r = 1		
	
	if mode == "ball" then
		if math_random(1,2) == 1 then 
			density = density * -1
		end
		r = math_random(1,4)
	end
	if mode == "line" then
		density = 1
		r = math_random(1,4)
	end
	if mode == "line_down" then
		density = density * -1
		r = math_random(1,4)
	end
	if mode == "line_up" then
		density = 1
		r = math_random(1,4)
	end
	if mode == "block" then
		r = 1
		density = 1
	end	
	
	if r == 1 then
		--start placing at -1,-1
		while i <= scan_radius do
			y = y - density						
			x = x - density				
			for a = 1, i, 1 do				
				local scanned_tile = surface.get_tile(x,y)				
				if scanned_tile.name ~= tilename then	
					table_insert(cluster_tiles, {name = tilename, position = {x,y}})
					surface.set_tiles(cluster_tiles,auto_correct)
					return true, x, y
				end
				x = x + density
			end		
			for a = 1, i, 1 do				
				local scanned_tile = surface.get_tile(x,y)
				if scanned_tile.name ~= tilename then	
					table_insert(cluster_tiles, {name = tilename, position = {x,y}})
					surface.set_tiles(cluster_tiles,auto_correct)
					return true, x, y
				end
				y = y + density
			end		
			for a = 1, i, 1 do				
				local scanned_tile = surface.get_tile(x,y)
				if scanned_tile.name ~= tilename then	
					table_insert(cluster_tiles, {name = tilename, position = {x,y}})
					surface.set_tiles(cluster_tiles,auto_correct)
					return true, x, y
				end
				x = x - density
			end		
			for a = 1, i, 1 do				
				local scanned_tile = surface.get_tile(x,y)
				if scanned_tile.name ~= tilename then	
					table_insert(cluster_tiles, {name = tilename, position = {x,y}})
					surface.set_tiles(cluster_tiles,auto_correct)
					return true, x, y
				end
				y = y - density
			end			
			i = i + 2
		end
	end
		
	if r == 2 then
		--start placing at 0,-1
		while i <= scan_radius do
			y = y - density						
			x = x - density
			for a = 1, i, 1 do
				x = x + density
				local scanned_tile = surface.get_tile(x,y)
				if scanned_tile.name ~= tilename then	
					table_insert(cluster_tiles, {name = tilename, position = {x,y}})
					surface.set_tiles(cluster_tiles,auto_correct)
					return true, x, y
				end
			end		
			for a = 1, i, 1 do
				y = y + density
				local scanned_tile = surface.get_tile(x,y)
				if scanned_tile.name ~= tilename then	
					table_insert(cluster_tiles, {name = tilename, position = {x,y}})
					surface.set_tiles(cluster_tiles,auto_correct)
					return true, x, y
				end
			end		
			for a = 1, i, 1 do
				x = x - density
				local scanned_tile = surface.get_tile(x,y)
				if scanned_tile.name ~= tilename then	
					table_insert(cluster_tiles, {name = tilename, position = {x,y}})
					surface.set_tiles(cluster_tiles,auto_correct)
					return true, x, y
				end
			end		
			for a = 1, i, 1 do
				y = y - density
				local scanned_tile = surface.get_tile(x,y)
				if scanned_tile.name ~= tilename then	
					table_insert(cluster_tiles, {name = tilename, position = {x,y}})
					surface.set_tiles(cluster_tiles,auto_correct)
					return true, x, y
				end
			end		
			i = i + 2
		end
	end
	
	if r == 3 then
		--start placing at 1,-1
		while i <= scan_radius do
			y = y - density						
			x = x + density								
			for a = 1, i, 1 do				
				local scanned_tile = surface.get_tile(x,y)
				if scanned_tile.name ~= tilename then	
					table_insert(cluster_tiles, {name = tilename, position = {x,y}})
					surface.set_tiles(cluster_tiles,auto_correct)
					return true, x, y
				end
				y = y + density
			end		
			for a = 1, i, 1 do				
				local scanned_tile = surface.get_tile(x,y)
				if scanned_tile.name ~= tilename then	
					table_insert(cluster_tiles, {name = tilename, position = {x,y}})
					surface.set_tiles(cluster_tiles,auto_correct)
					return true, x, y
				end
				x = x - density
			end		
			for a = 1, i, 1 do				
				local scanned_tile = surface.get_tile(x,y)
				if scanned_tile.name ~= tilename then	
					table_insert(cluster_tiles, {name = tilename, position = {x,y}})
					surface.set_tiles(cluster_tiles,auto_correct)
					return true, x, y
				end
				y = y - density
			end
			for a = 1, i, 1 do				
				local scanned_tile = surface.get_tile(x,y)
				if scanned_tile.name ~= tilename then	
					table_insert(cluster_tiles, {name = tilename, position = {x,y}})
					surface.set_tiles(cluster_tiles,auto_correct)
					return true, x, y
				end
				x = x + density
			end				
			i = i + 2
		end
	end
	
	if r == 4 then
		--start placing at 1,0
		while i <= scan_radius do
			y = y - density
			x = x + density				
			for a = 1, i, 1 do
				y = y + density
				local scanned_tile = surface.get_tile(x,y)
				if scanned_tile.name ~= tilename then	
					table_insert(cluster_tiles, {name = tilename, position = {x,y}})
					surface.set_tiles(cluster_tiles,auto_correct)
					return true, x, y
				end
			end		
			for a = 1, i, 1 do
				x = x - density
				local scanned_tile = surface.get_tile(x,y)
				if scanned_tile.name ~= tilename then	
					table_insert(cluster_tiles, {name = tilename, position = {x,y}})
					surface.set_tiles(cluster_tiles,auto_correct)
					return true, x, y
				end
			end		
			for a = 1, i, 1 do
				y = y - density
				local scanned_tile = surface.get_tile(x,y)
				if scanned_tile.name ~= tilename then	
					table_insert(cluster_tiles, {name = tilename, position = {x,y}})
					surface.set_tiles(cluster_tiles,auto_correct)
					return true, x, y
				end
			end
			for a = 1, i, 1 do
				x = x + density
				local scanned_tile = surface.get_tile(x,y)
				if scanned_tile.name ~= tilename then	
					table_insert(cluster_tiles, {name = tilename, position = {x,y}})
					surface.set_tiles(cluster_tiles,auto_correct)
					return true, x, y
				end
			end			
			i = i + 2
		end
	end	
	return false
end

local function create_tile_cluster(tilename,position,amount)
	local mode = "ball"
	local cluster_tiles = {}
	local surface = game.surfaces["surface"]
	local pos = position
	local x = pos.x
	local y = pos.y
	for i = 1, amount, 1 do
		local b,x,y = find_tile_placement_spot_around_target_position(tilename, pos, mode)
		if b == true then						
			if 1 == math_random(1,16) then
				pos.x = x
				pos.y = y
			end			
		end
		if b == false then return false,x,y end
		if i >= amount then return true,x,y end
	end		
end

function biter_battles_terrain.generate_spawn_water_pond()
	local x = 1
	local surface = game.surfaces["surface"]
	for _, silo in pairs(global.rocket_silo) do
		local pos = {}
		local wreck_pos = {}
		pos["x"]=silo.position.x + 60*x
		pos["y"]=silo.position.y - 5*x
		create_tile_cluster("water-green",pos,450)			
		local p = surface.find_non_colliding_position("big-ship-wreck-1", {pos["x"],pos["y"]-3*x}, 20,1)
		local e = surface.create_entity {name="big-ship-wreck-1", position=p, force=silo.force.name}
		e.insert({name = 'copper-cable', count = 7})
		e.insert({name = 'iron-stick', count = 3})		
		local p = surface.find_non_colliding_position("big-ship-wreck-3", {pos.x-3*x,pos.y}, 20,1)
		local e = surface.create_entity {name="big-ship-wreck-3", position=p, force=silo.force.name}						
		e.insert({name = 'land-mine', count = 6})							
		pos["x"]=silo.position.x - 80*x
		pos["y"]=silo.position.y - 60*x
		create_tile_cluster("water-green",pos,300)
		local p = surface.find_non_colliding_position("big-ship-wreck-2", {pos.x+3*x,pos.y-5*x}, 20,1)
		local e = surface.create_entity {name="big-ship-wreck-2", position=p, force=silo.force.name}
		e.insert({name = 'empty-barrel', count = 1})
		e.insert({name = 'lubricant-barrel', count = 2})
		local p = surface.find_non_colliding_position("crude-oil", {pos.x-5*x,pos.y+5*x}, 50,1)
		local e = surface.create_entity {name="crude-oil", position=p, amount=225000}		
		x = -1
	end
	
	for x = -200, 200, 1 do
		for y = -200, 200, 1 do						
			local t = surface.get_tile(x,y)
			if t.name == "water-green" then 
				if surface.can_place_entity{name="fish", position={x,y}} and math_random(1,12) == 1 then
					surface.create_entity {name="fish", position={x,y}} 
				end			
			end			
		end
	end	
end

function biter_battles_terrain.clear_spawn_ores()
	local surface = game.surfaces["surface"]			
	for x = -200,200,1 do
		for y = -200,200,1 do
			local tile_distance_to_center =  math.sqrt(x^2 + y^2)
			if tile_distance_to_center < 150 then
				local entities = surface.find_entities({{x, y}, {x+1, y+1}})
				for _, e in pairs(entities) do
					if e.type == "resource" then
						e.destroy()
					end
				end												
			end
		end
	end
end

function biter_battles_terrain.generate_market()		
	local surface = game.surfaces["surface"]		
	for z = -1, 1, 2 do
		local f = "north"
		if z == 1 then f = "south" end
		local x = global.rocket_silo[f].position.x + (80 * z)
		local y = global.rocket_silo[f].position.y + (60 * z)
		local p = surface.find_non_colliding_position("market",{x,y}, 20,1)  
		local m = surface.create_entity {name="market", position=p, force=f}
		local entities = surface.find_entities({{m.position.x-1, m.position.y-1}, {m.position.x+1, m.position.y+1}})
		for _, ee in pairs(entities) do
			if ee.type == "simple-entity" or ee.type == "resource" or ee.type == "tree" then
				ee.destroy()
			end
		end		
		m.minable=false
		m.destructible=false
		m.add_market_item{price={{"raw-fish", 1}}, offer={type="give-item", item="small-electric-pole", count=2}}
		m.add_market_item{price={{"raw-fish", 1}}, offer={type="give-item", item="firearm-magazine", count=2}}
		m.add_market_item{price={{"raw-fish", 2}}, offer={type="give-item", item="grenade"}}
		m.add_market_item{price={{"raw-fish", 2}}, offer={type="give-item", item="land-mine", count=1}}
		m.add_market_item{price={{"raw-fish", 5}}, offer={type="give-item", item="light-armor"}}
		m.add_market_item{price={{"raw-fish", 8}}, offer={type="give-item", item="radar"}}
		m.add_market_item{price={{"iron-ore", 50}}, offer={type="give-item", item="raw-fish"}}		
		m.add_market_item{price={{"copper-ore", 50}}, offer={type="give-item", item="raw-fish"}}
		m.add_market_item{price={{"stone", 50}}, offer={type="give-item", item="raw-fish"}}	
		m.add_market_item{price={{"coal", 50}}, offer={type="give-item", item="raw-fish"}}			
	end
end

function biter_battles_terrain.generate_artillery()	
	local tiles = {}
	local surface = game.surfaces["surface"]
	global.spawn_artillery = {}	
	for z = -1, 1, 2 do
		local f = "north"
		if z == 1 then f = "south" end
		global.spawn_artillery[f] = surface.create_entity {name="artillery-turret", position={55*z, 26*z}, force=f}
		local e = global.spawn_artillery[f]
		e.minable=false
		e.destructible=false
		local entities = surface.find_entities({{e.position.x-3, e.position.y-4}, {e.position.x+3, e.position.y+4}})
		for _, ee in pairs(entities) do
			if ee.type == "simple-entity" or ee.type == "resource" or ee.type == "tree" then
				ee.destroy()
			end
		end
		local m = surface.create_entity {name="market", position={e.position.x, e.position.y + (3*z)}, force=f}
		m.minable=false
		m.destructible=false				
		m.add_market_item{price={{"raw-fish", 2}}, offer={type="give-item", item="grenade"}}
		m.add_market_item{price={{"raw-fish", 1}}, offer={type="give-item", item="land-mine", count=1}}
		m.add_market_item{price={{"raw-fish", 60}}, offer={type="give-item", item="artillery-shell"}}
		m.add_market_item{price={{"raw-fish", 20}}, offer={type="give-item", item="artillery-targeting-remote"}}		
		for y = -1,1,1 do
			for x = -2,2,1 do
				table_insert(tiles, {name = "refined-hazard-concrete-left", position = {e.position.x + x, e.position.y + y}}) 				
			end
		end
		for y = -2,2,1 do
			for x = -1,1,1 do
				table_insert(tiles, {name = "refined-hazard-concrete-left", position = {e.position.x + x, e.position.y + y}}) 				
			end
		end		 
	end		
	surface.set_tiles(tiles,true)	
end

function biter_battles_terrain.generate_spawn_ores(ore_layout)		
	local surface = game.surfaces["surface"]
	local seed = game.surfaces[1].map_gen_settings.seed
	local tiles = {}
	--generate ores around silos
	local ore_layout = "windows"
	--local ore_layout = "4squares"
	local ore_amount = 850
			
	if ore_layout == "4squares" then
		local size = 22			
		for _, rocket_silo in pairs(global.rocket_silo) do
			local tiles = {}
			for x = (size+1)*-1, size+1, 1 do
				for y = (size+1)*-1, size+1, 1 do
					table_insert(tiles, {name = "stone-path", position = {rocket_silo.position.x + x,rocket_silo.position.y + y}})							
				end
			end
			surface.set_tiles(tiles,true)
			local entities = surface.find_entities({{(rocket_silo.position.x-4)-size/2, (rocket_silo.position.y-5)-size/2}, {rocket_silo.position.x+4+size/2, rocket_silo.position.y+5+size/2}})
			for _, entity in pairs(entities) do
				if entity.type == "simple-entity" or entity.type == "tree" or entity.type == "resource" then
					entity.destroy()					
				end
			end					
		end							
		for x = size*-1, size, 1 do
			for y = size*-1, size, 1 do				
				if x > 0 and y < 0 then
					if surface.can_place_entity {name="stone", position={global.rocket_silo["south"].position.x + x,global.rocket_silo["south"].position.y + y}, amount=ore_amount} then
						surface.create_entity {name="stone", position={global.rocket_silo["south"].position.x + x,global.rocket_silo["south"].position.y + y}, amount=ore_amount}
					end
				end
				if x < 0 and y < 0 then
					if surface.can_place_entity {name="coal", position={global.rocket_silo["south"].position.x + x,global.rocket_silo["south"].position.y + y}, amount=ore_amount} then
						surface.create_entity {name="coal", position={global.rocket_silo["south"].position.x + x,global.rocket_silo["south"].position.y + y}, amount=ore_amount}
					end
				end
				if x < 0 and y > 0 then
					if surface.can_place_entity {name="copper-ore", position={global.rocket_silo["south"].position.x + x,global.rocket_silo["south"].position.y + y}, amount=ore_amount} then
						surface.create_entity {name="copper-ore", position={global.rocket_silo["south"].position.x + x,global.rocket_silo["south"].position.y + y}, amount=ore_amount}
					end
				end
				if x > 0 and y > 0 then
					if surface.can_place_entity {name="iron-ore", position={global.rocket_silo["south"].position.x + x,global.rocket_silo["south"].position.y + y}, amount=ore_amount} then
						surface.create_entity {name="iron-ore", position={global.rocket_silo["south"].position.x + x,global.rocket_silo["south"].position.y + y}, amount=ore_amount}
					end
				end					
				if x < 0 and y > 0 then
					if surface.can_place_entity {name="stone", position={global.rocket_silo["north"].position.x + x,global.rocket_silo["north"].position.y + y}, amount=ore_amount} then
						surface.create_entity {name="stone", position={global.rocket_silo["north"].position.x + x,global.rocket_silo["north"].position.y + y}, amount=ore_amount}
					end
				end
				if x > 0 and y > 0 then
					if surface.can_place_entity {name="coal", position={global.rocket_silo["north"].position.x + x,global.rocket_silo["north"].position.y + y}, amount=ore_amount} then
						surface.create_entity {name="coal", position={global.rocket_silo["north"].position.x + x,global.rocket_silo["north"].position.y + y}, amount=ore_amount}
					end
				end
				if x > 0 and y < 0 then
					if surface.can_place_entity {name="copper-ore", position={global.rocket_silo["north"].position.x + x,global.rocket_silo["north"].position.y + y}, amount=ore_amount} then
						surface.create_entity {name="copper-ore", position={global.rocket_silo["north"].position.x + x,global.rocket_silo["north"].position.y + y}, amount=ore_amount}
					end
				end
				if x < 0 and y < 0 then
					if surface.can_place_entity {name="iron-ore", position={global.rocket_silo["north"].position.x + x,global.rocket_silo["north"].position.y + y}, amount=ore_amount} then
						surface.create_entity {name="iron-ore", position={global.rocket_silo["north"].position.x + x,global.rocket_silo["north"].position.y + y}, amount=ore_amount}
					end
				end
			end
		end
		for _, rocket_silo in pairs(global.rocket_silo) do
			local entities = surface.find_entities({{rocket_silo.position.x-5, rocket_silo.position.y-6}, {rocket_silo.position.x+5, rocket_silo.position.y+6}})
			for _, entity in pairs(entities) do
				if entity.type == "resource" then
					entity.destroy()					
				end
			end	
		end
	end
	
	if ore_layout == "windows" then		 
			
		local m1 = 0.09
		local m2 = 0
		local m3 = 1
		local m4 = 23
				
		for x = m4*-1, m4, 1 do						
			local noise = simplex_noise(x*m1, 1*m1,seed+50000)			
			noise = noise*m2 + m3						
			for y = (m4+1)*-1*noise, m4*noise, 1 do				
				table_insert(tiles, {name = "stone-path", position = {global.rocket_silo["north"].position.x + x,global.rocket_silo["north"].position.y + y}})						
			end
			local noise = simplex_noise(x*m1, 1*m1,seed+60000)
			noise = noise*m2 + m3
			for y = (m4+1)*-1*noise, m4*noise, 1 do	
				table_insert(tiles, {name = "stone-path", position = {global.rocket_silo["south"].position.x + x,global.rocket_silo["south"].position.y + y}})
			end
		end
		for y = (m4+1)*-1, m4, 1 do
			local noise = simplex_noise(y*m1, 1*m1,seed+50000)
			noise = noise*m2 + m3
			for x = m4*-1*noise, m4*noise, 1 do				
				table_insert(tiles, {name = "stone-path", position = {global.rocket_silo["north"].position.x + x,global.rocket_silo["north"].position.y + y}})	
			end
			local noise = simplex_noise(y*m1, 1*m1,seed+60000)
			noise = noise*m2 + m3
			for x = m4*-1*noise, m4*noise, 1 do				
				table_insert(tiles, {name = "stone-path", position = {global.rocket_silo["south"].position.x + x,global.rocket_silo["south"].position.y + y}})					
			end
		end
		surface.set_tiles(tiles,true)

		
		local ore = {"stone","stone","stone","stone","coal","coal","coal","coal","coal","copper-ore","copper-ore","copper-ore","copper-ore","copper-ore","iron-ore","iron-ore","iron-ore","iron-ore","iron-ore"}
		for z = 1, 19, 1 do
			for x = -4-z, 4+z, 1 do
				for y = -5-z, 4+z, 1 do				
					if surface.can_place_entity {name=ore[z], position={global.rocket_silo["south"].position.x + x,global.rocket_silo["south"].position.y + y}, amount=ore_amount} then
						surface.create_entity {name=ore[z], position={global.rocket_silo["south"].position.x + x,global.rocket_silo["south"].position.y + y}, amount=ore_amount}
					end				
				end
			end
		end
		for z = 1, 19, 1 do
			for x = -4-z, 4+z, 1 do
				for y = -5-z, 4+z, 1 do				
					if surface.can_place_entity {name=ore[z], position={global.rocket_silo["north"].position.x + x,global.rocket_silo["north"].position.y + y}, amount=ore_amount} then
						surface.create_entity {name=ore[z], position={global.rocket_silo["north"].position.x + x,global.rocket_silo["north"].position.y + y}, amount=ore_amount}
					end				
				end
			end
		end
	end
	
	for _, rocket_silo in pairs(global.rocket_silo) do
		local entities = surface.find_entities({{rocket_silo.position.x-4, rocket_silo.position.y-5}, {rocket_silo.position.x+4, rocket_silo.position.y+5}})
		for _, entity in pairs(entities) do
			if entity.type == "resource" then
				entity.destroy()					
			end
		end	
	end
end

event.add(defines.events.on_chunk_generated, on_chunk_generated)

return biter_battles_terrain