-- Minetest: builtin/misc_helpers.lua

--------------------------------------------------------------------------------
function basic_dump2(o)
	if type(o) == "number" then
		return tostring(o)
	elseif type(o) == "string" then
		return string.format("%q", o)
	elseif type(o) == "boolean" then
		return tostring(o)
	elseif type(o) == "function" then
		return "<function>"
	elseif type(o) == "userdata" then
		return "<userdata>"
	elseif type(o) == "nil" then
		return "nil"
	else
		error("cannot dump a " .. type(o))
		return nil
	end
end

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function dump2(o, name, dumped)
	name = name or "_"
	dumped = dumped or {}
	io.write(name, " = ")
	if type(o) == "number" or type(o) == "string" or type(o) == "boolean"
			or type(o) == "function" or type(o) == "nil"
			or type(o) == "userdata" then
		io.write(basic_dump2(o), "\n")
	elseif type(o) == "table" then
		if dumped[o] then
			io.write(dumped[o], "\n")
		else
			dumped[o] = name
			io.write("{}\n") -- new table
			for k,v in pairs(o) do
				local fieldname = string.format("%s[%s]", name, basic_dump2(k))
				dump2(v, fieldname, dumped)
			end
		end
	else
		error("cannot dump a " .. type(o))
		return nil
	end
end

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function dump(o, dumped)
	dumped = dumped or {}
	if type(o) == "number" then
		return tostring(o)
	elseif type(o) == "string" then
		return string.format("%q", o)
	elseif type(o) == "table" then
		if dumped[o] then
			return "<circular reference>"
		end
		dumped[o] = true
		local t = {}
		for k,v in pairs(o) do
			t[#t+1] = "[" .. dump(k, dumped) .. "] = " .. dump(v, dumped)
		end
		return "{" .. table.concat(t, ", ") .. "}"
	elseif type(o) == "boolean" then
		return tostring(o)
	elseif type(o) == "function" then
		return "<function>"
	elseif type(o) == "userdata" then
		return "<userdata>"
	elseif type(o) == "nil" then
		return "nil"
	else
		error("cannot dump a " .. type(o))
		return nil
	end
end

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function string:split(sep)
	local sep, fields = sep or ",", {}
	local pattern = string.format("([^%s]+)", sep)
	self:gsub(pattern, function(c) fields[#fields+1] = c end)
	return fields
end

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function string:trim()
	return (self:gsub("^%s*(.-)%s*$", "%1"))
end

assert(string.trim("\n \t\tfoo bar\t ") == "foo bar")



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function math.hypot(x, y)
	local t
	x = math.abs(x)
	y = math.abs(y)
	t = math.min(x, y)
	x = math.max(x, y)
	if x == 0 then return 0 end
	t = t / x
	return x * math.sqrt(1 + t * t)
end

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function explode_textlist_event(text)
	
	local retval = {}
	retval.typ = "INV"
	
	local parts = text:split(":")
				
	if #parts == 2 then
		retval.typ = parts[1]:trim()
		retval.index= tonumber(parts[2]:trim())
		
		if type(retval.index) ~= "number" then
			retval.typ = "INV"
		end
	end
	
	return retval
end

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function get_last_folder(text,count)
	local parts = text:split(DIR_DELIM)
	
	if count == nil then
		return parts[#parts]
	end
	
	local retval = ""
	for i=1,count,1 do
		retval = retval .. parts[#parts - (count-i)] .. DIR_DELIM
	end
	
	return retval
end

--------------------------------------------------------------------------------
function cleanup_path(temppath)
	
	local parts = temppath:split("-")
	temppath = ""	
	for i=1,#parts,1 do
		if temppath ~= "" then
			temppath = temppath .. "_"
		end
		temppath = temppath .. parts[i]
	end
	
	parts = temppath:split(".")
	temppath = ""	
	for i=1,#parts,1 do
		if temppath ~= "" then
			temppath = temppath .. "_"
		end
		temppath = temppath .. parts[i]
	end
	
	parts = temppath:split("'")
	temppath = ""	
	for i=1,#parts,1 do
		if temppath ~= "" then
			temppath = temppath .. ""
		end
		temppath = temppath .. parts[i]
	end
	
	parts = temppath:split(" ")
	temppath = ""	
	for i=1,#parts,1 do
		if temppath ~= "" then
			temppath = temppath
		end
		temppath = temppath .. parts[i]
	end
	
	return temppath
end

--------------------------------------------------------------------------------
-- mainmenu only functions
--------------------------------------------------------------------------------
if engine ~= nil then
	engine.get_game = function(index)
		local games = game.get_games()
		
		if index > 0 and index <= #games then
			return games[index]
		end
		
		return nil
	end
	
	--------------------------------------------------------------------------------
	function fs_escape_string(text)
		if text ~= nil then
			while (text:find("\r\n") ~= nil) do
				local newtext = text:sub(1,text:find("\r\n")-1)
				newtext = newtext .. " " .. text:sub(text:find("\r\n")+3)
				
				text = newtext
			end
			
			while (text:find("\n") ~= nil) do
				local newtext = text:sub(1,text:find("\n")-1)
				newtext = newtext .. " " .. text:sub(text:find("\n")+1)
				
				text = newtext
			end
			
			while (text:find("\r") ~= nil) do
				local newtext = text:sub(1,text:find("\r")-1)
				newtext = newtext .. " " .. text:sub(text:find("\r")+1)
				
				text = newtext
			end
			
			text = string.gsub(text,"\\","\\\\")
			text = string.gsub(text,"%]","\\]")
			text = string.gsub(text,"%[","\\[")
			text = string.gsub(text,";","\\;")
			text = string.gsub(text,",","\\,")
		end
		return text
	end
end

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-- core only fct
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if minetest ~= nil then
	--------------------------------------------------------------------------------
	function minetest.pos_to_string(pos)
		return "(" .. pos.x .. "," .. pos.y .. "," .. pos.z .. ")"
	end
end