local S = minetest.get_translator(minetest.get_current_modname())


-- Convenience function because the cauldron nodeboxes are very similar
local floors_table = {
	[0]=-0.1875,  -- empty
	[1]=1/16,  -- 1/3 filled
	[2]=4/16,  -- 2/3 filled
	[3]=7/16,  -- full
}

local create_cauldron_nodebox = function(water_level)
	local floor_y = floors_table[water_level]
	return {
		type = "fixed",
		fixed = {
			{-0.5, -0.1875, -0.5, -0.375, 0.5, 0.5}, -- Left wall
			{0.375, -0.1875, -0.5, 0.5, 0.5, 0.5}, -- Right wall
			{-0.375, -0.1875, 0.375, 0.375, 0.5, 0.5}, -- Back wall
			{-0.375, -0.1875, -0.5, 0.375, 0.5, -0.375}, -- Front wall
			{-0.5, -0.3125, -0.5, 0.5, floor_y, 0.5}, -- Floor
			{-0.5, -0.5, -0.5, -0.375, -0.3125, -0.25}, -- Left front foot, part 1
			{-0.375, -0.5, -0.5, -0.25, -0.3125, -0.375}, -- Left front foot, part 2
			{-0.5, -0.5, 0.25, -0.375, -0.3125, 0.5}, -- Left back foot, part 1
			{-0.375, -0.5, 0.375, -0.25, -0.3125, 0.5}, -- Left back foot, part 2
			{0.375, -0.5, 0.25, 0.5, -0.3125, 0.5}, -- Right back foot, part 1
			{0.25, -0.5, 0.375, 0.375, -0.3125, 0.5}, -- Right back foot, part 2
			{0.375, -0.5, -0.5, 0.5, -0.3125, -0.25}, -- Right front foot, part 1
			{0.25, -0.5, -0.5, 0.375, -0.3125, -0.375}, -- Right front foot, part 2
		}
	}
end

-- Generate nodeboxes for cauldrons, (0=empty, 1=1/3 filled, 2=2/3 filled, 3=full)
mcl_cauldrons.cauldron_nodeboxes = {}
for w=0,3 do
	mcl_cauldrons.cauldron_nodeboxes[w] = create_cauldron_nodebox(w)
end


-- The normal Lua means of inheritance uses setmetatable.
-- For node definitions, minetest.register_node() breaks/overwrite the metatable for its own use.
-- This function copies in the "old" keys/values, to let them be overwritten by another (newer) table.
-- Nested tables are recursively merged/copied, so nested keys may be selectively overridden.
-- Modifying the returned table does not risk mangling the source/parent table.
-- This workaround happens to work as declarative objects do not change after instantiation.
local function merge_tables(a,b)
	local result = {}
	for k,v in pairs(a) do result[k]=v end
	for k,v in pairs(b) do
		if type(a[k]) == "table" then
			-- recursive merge table (with copy).
			result[k] = merge_tables(a[k], v)
		else
			result[k] = v
		end
	end
	return result
end


function mcl_cauldrons.empty_cauldron_on_fill(node, change_levels, substance)
	-- base rules for cauldrons.
	if change_levels <= 0 then
		-- no change.
		return nil
	end
	local old_level = mcl_cauldrons.get_level(node)
	local whole, fraction = math.modf(change_levels)
	local new_level
	if fraction > 0 then
		if math.random() < fraction then
			whole = whole + 1
		end
	end
	if (substance and mcl_cauldrons.has_substance(node, substance)) or (substance == nil) then
		-- same substance, add more.
		new_level = old_level + whole
	else
		-- different substance, delete old content.
		new_level = whole
	end
	-- clamp 0 through 3 inclusive.
	new_level = math.max(0, math.min(new_level, 3))
	local newnode = mcl_cauldrons.set_level(node, new_level, substance)
	return newnode
end

function mcl_cauldrons.empty_cauldron_on_drain(node, change_levels, substance)
	-- base rules for cauldrons.
	if change_levels <= 0 then
		-- no change.
		return nil
	end
	if (substance and not mcl_cauldrons.has_substance(node, substance)) then
		-- different substance, cannot drain.
		return nil
	end
	local old_level = mcl_cauldrons.get_level(node)
	local whole, fraction = math.modf(change_levels)
	local new_level
	if fraction > 0 then
		if math.random() < fraction then
			whole = whole + 1
		end
	end
	if (whole > old_level) then
		-- insufficient amount, no change.
		return nil
	end
	-- same substance, drain.
	new_level = old_level - whole
	-- clamp 0 through 3 inclusive.
	new_level = math.max(0, math.min(new_level, 3))
	local newnode = mcl_cauldrons.set_level(node, new_level, substance)
	return newnode
end

-- Empty cauldron
mcl_cauldrons.register_cauldron_node("mcl_cauldrons:cauldron", {
	description = S("Cauldron"),
	_tt_help = S("Stores water"),
	_doc_items_longdesc = S("Cauldrons are used to store water and slowly fill up under rain."),
	_doc_items_usagehelp = S("Place a water pucket into the cauldron to fill it with water. Place an empty bucket on a full cauldron to retrieve the water. Place a water bottle into the cauldron to fill the cauldron to one third with water. Place a glass bottle in a cauldron with water to retrieve one third of the water."),
	wield_image = "mcl_cauldrons_cauldron.png",
	inventory_image = "mcl_cauldrons_cauldron.png",
	use_texture_alpha = minetest.features.use_texture_alpha_string_modes and "opaque" or false,
	drawtype = "nodebox",
	paramtype = "light",
	is_ground_content = false,
	groups = {pickaxey=1, deco_block=1, cauldron=1},
	node_box = mcl_cauldrons.cauldron_nodeboxes[0],
	selection_box = { type = "regular" },
	tiles = {
		"mcl_cauldrons_cauldron_inner.png^mcl_cauldrons_cauldron_top.png",
		"mcl_cauldrons_cauldron_inner.png^mcl_cauldrons_cauldron_bottom.png",
		"mcl_cauldrons_cauldron_side.png"
	},
	sounds = mcl_sounds.node_sound_metal_defaults(),
	_mcl_hardness = 2,
	_mcl_blast_resistance = 2,

	_mcl_on_fill = function(node, change_levels, substance)
		return mcl_cauldrons.empty_cauldron_on_fill(node, change_levels, substance)
	end,
	_mcl_on_drain = function(node, change_levels, substance)
		return mcl_cauldrons.empty_cauldron_on_drain(node, change_levels, substance)
	end,
})


-- water cauldron as extension of empty cauldron.
mcl_cauldrons.register_cauldron_node("mcl_cauldrons:cauldron_water_1",
	merge_tables(mcl_cauldrons.registered_cauldrons["mcl_cauldrons:cauldron"], {
	description = S("Cauldron (1/3 Water)"),
	groups = {
		pickaxey = 1,
		cauldron = 1,
		cauldron_filled = 1,
		cauldron_maximum = 3,
		cauldron_water = 1,
		},
	node_box = mcl_cauldrons.cauldron_nodeboxes[1],
	collision_box = mcl_cauldrons.cauldron_nodeboxes[0],
	tiles = {
			"(default_water_source_animated.png^[verticalframe:16:0"..")^mcl_cauldrons_cauldron_top.png",
			"mcl_cauldrons_cauldron_inner.png^mcl_cauldrons_cauldron_bottom.png",
			"mcl_cauldrons_cauldron_side.png"
	},
	drop = "mcl_cauldrons:cauldron",
}), "mcl_cauldrons:cauldron")

-- water cauldron 2/3 as extension of 1/3.
mcl_cauldrons.register_cauldron_node("mcl_cauldrons:cauldron_water_2",
	merge_tables(mcl_cauldrons.registered_cauldrons["mcl_cauldrons:cauldron_water_1"], {
	description = S("Cauldron (2/3 Water)"),
	groups = {
		cauldron_filled = 2,
		},
	node_box = mcl_cauldrons.cauldron_nodeboxes[2],
}), "mcl_cauldrons:cauldron")

-- water cauldron 3/3 as extension of 1/3.
mcl_cauldrons.register_cauldron_node("mcl_cauldrons:cauldron_water_3",
	merge_tables(mcl_cauldrons.registered_cauldrons["mcl_cauldrons:cauldron_water_1"], {
	description = S("Cauldron (3/3 Water)"),
	groups = {
		cauldron_filled = 3,
		},
	node_box = mcl_cauldrons.cauldron_nodeboxes[3],
}), "mcl_cauldrons:cauldron")

if minetest.get_modpath("mclx_core") then
	-- river water cauldron as extension of empty cauldron.
	mcl_cauldrons.register_cauldron_node("mcl_cauldrons:cauldron_river_water_1",
		merge_tables(mcl_cauldrons.registered_cauldrons["mcl_cauldrons:cauldron"], {
		description = S("Cauldron (1/3 River Water)"),
		groups = {
			pickaxey = 1,
			cauldron = 1,
			cauldron_filled = 1,
			cauldron_maximum = 3,
			cauldron_river_water = 1,
			},
		node_box = mcl_cauldrons.cauldron_nodeboxes[1],
		collision_box = mcl_cauldrons.cauldron_nodeboxes[0],
		tiles = {
				"(default_river_water_source_animated.png^[verticalframe:16:0"..")^mcl_cauldrons_cauldron_top.png",
				"mcl_cauldrons_cauldron_inner.png^mcl_cauldrons_cauldron_bottom.png",
				"mcl_cauldrons_cauldron_side.png"
		},
		drop = "mcl_cauldrons:cauldron",
	}), "mcl_cauldrons:cauldron")
	-- water cauldron 2/3 as extension of 1/3.
	mcl_cauldrons.register_cauldron_node("mcl_cauldrons:cauldron_river_water_2",
		merge_tables(mcl_cauldrons.registered_cauldrons["mcl_cauldrons:cauldron_river_water_1"], {
		description = S("Cauldron (2/3 River Water)"),
		groups = {
			cauldron_filled = 2,
			},
		node_box = mcl_cauldrons.cauldron_nodeboxes[2],
	}), "mcl_cauldrons:cauldron")
	-- water cauldron 3/3 as extension of 1/3.
	mcl_cauldrons.register_cauldron_node("mcl_cauldrons:cauldron_river_water_3",
		merge_tables(mcl_cauldrons.registered_cauldrons["mcl_cauldrons:cauldron_river_water_1"], {
		description = S("Cauldron (3/3 River Water)"),
		groups = {
			cauldron_filled = 3,
			},
		node_box = mcl_cauldrons.cauldron_nodeboxes[3],
	}), "mcl_cauldrons:cauldron")
end


-- Crafting recipe: Cauldron
minetest.register_craft({
	output = "mcl_cauldrons:cauldron",
	recipe = {
		{ "mcl_core:iron_ingot", "", "mcl_core:iron_ingot" },
		{ "mcl_core:iron_ingot", "", "mcl_core:iron_ingot" },
		{ "mcl_core:iron_ingot", "mcl_core:iron_ingot", "mcl_core:iron_ingot" },
	}
})

minetest.register_abm({
	label = "cauldrons",
	nodenames = {"group:cauldron_filled"},
	interval = 0.5,
	chance = 1,
	action = function(pos, node)
		local EXTINGUISHING_RADIUS = 0.4
		for _, obj in pairs(minetest.get_objects_inside_radius(pos, EXTINGUISHING_RADIUS)) do
			if mcl_burning.is_burning(obj) then
				local newnode = mcl_cauldrons.drain_levels(node, 1, "cauldron_water")
				if node ~= newnode then
					-- extinguishing requires 1 level of water from cauldron.
					minetest.swap_node(pos, newnode)
					mcl_burning.extinguish(obj)
					break
				end
			end
		end
	end
})


-- backwards compatibility
local aliases = {
	-- key=old/legacy name; value=current name
	["mcl_cauldrons:cauldron_1"] = "mcl_cauldrons:cauldron_water_1",
	["mcl_cauldrons:cauldron_2"] = "mcl_cauldrons:cauldron_water_2",
	["mcl_cauldrons:cauldron_3"] = "mcl_cauldrons:cauldron_water_3",
	["mcl_cauldrons:cauldron_1r"] = "mcl_cauldrons:cauldron_river_water_1",
	["mcl_cauldrons:cauldron_2r"] = "mcl_cauldrons:cauldron_river_water_2",
	["mcl_cauldrons:cauldron_3r"] = "mcl_cauldrons:cauldron_river_water_3",
}
for legacy, current in pairs(aliases) do
	minetest.register_alias(legacy, current)
end