local S = unified_inventory.gettext
local F = minetest.formspec_escape

minetest.register_privilege("creative", {
	description = S("Can use the creative inventory"),
	give_to_singleplayer = false,
})

minetest.register_privilege("ui_full", {
	description = S("Forces Unified Inventory to be displayed in Full mode if Lite mode is configured globally"),
	give_to_singleplayer = false,
})


local trash = minetest.create_detached_inventory("trash", {
	--allow_put = function(inv, listname, index, stack, player)
	--	if unified_inventory.is_creative(player:get_player_name()) then
	--		return stack:get_count()
	--	else
	--		return 0
	--	end
	--end,
	on_put = function(inv, listname, index, stack, player)
		inv:set_stack(listname, index, nil)
		local player_name = player:get_player_name()
		minetest.sound_play("trash", {to_player=player_name, gain = 1.0})
	end,
})
trash:set_size("main", 1)

unified_inventory.register_button("craft", {
	type = "image",
	image = "ui_craft_icon.png",
	tooltip = S("Crafting Grid")
})

unified_inventory.register_button("craftguide", {
	type = "image",
	image = "ui_craftguide_icon.png",
	tooltip = S("Crafting Guide")
})

unified_inventory.register_button("home_gui_set", {
	type = "image",
	image = "ui_sethome_icon.png",
	tooltip = S("Set home position"),
	hide_lite=true,
	action = function(player)
		local player_name = player:get_player_name()
		if minetest.check_player_privs(player_name, {home=true}) then
			unified_inventory.set_home(player, player:getpos())
			local home = unified_inventory.home_pos[player_name]
			if home ~= nil then
				minetest.sound_play("dingdong",
						{to_player=player_name, gain = 1.0})
				minetest.chat_send_player(player_name,
					S("Home position set to: %s"):format(minetest.pos_to_string(home)))
			end
		else
			minetest.chat_send_player(player_name,
				S("You don't have the \"home\" privilege!"))
			unified_inventory.set_inventory_formspec(player, unified_inventory.current_page[player_name])
		end
	end,
	condition = function(player)
		return minetest.check_player_privs(player:get_player_name(), {home=true})
	end,
})

unified_inventory.register_button("home_gui_go", {
	type = "image",
	image = "ui_gohome_icon.png",
	tooltip = S("Go home"),
	hide_lite=true,
	action = function(player)
		local player_name = player:get_player_name()
		if minetest.check_player_privs(player_name, {home=true}) then
			minetest.sound_play("teleport",
				{to_player=player:get_player_name(), gain = 1.0})
			unified_inventory.go_home(player)
		else
			minetest.chat_send_player(player_name,
				S("You don't have the \"home\" privilege!"))
			unified_inventory.set_inventory_formspec(player, unified_inventory.current_page[player_name])
		end
	end,
	condition = function(player)
		return minetest.check_player_privs(player:get_player_name(), {home=true})
	end,
})

unified_inventory.register_button("misc_set_day", {
	type = "image",
	image = "ui_sun_icon.png",
	tooltip = S("Set time to day"),
	hide_lite=true,
	action = function(player)
		local player_name = player:get_player_name()
		if minetest.check_player_privs(player_name, {settime=true}) then
			minetest.sound_play("birds",
					{to_player=player_name, gain = 1.0})
			minetest.set_timeofday((6000 % 24000) / 24000)
			minetest.chat_send_player(player_name,
				S("Time of day set to 6am"))
		else
			minetest.chat_send_player(player_name,
				S("You don't have the settime privilege!"))
			unified_inventory.set_inventory_formspec(player, unified_inventory.current_page[player_name])
		end
	end,
	condition = function(player)
		return minetest.check_player_privs(player:get_player_name(), {settime=true})
	end,
})

unified_inventory.register_button("misc_set_night", {
	type = "image",
	image = "ui_moon_icon.png",
	tooltip = S("Set time to night"),
	hide_lite=true,
	action = function(player)
		local player_name = player:get_player_name()
		if minetest.check_player_privs(player_name, {settime=true}) then
			minetest.sound_play("owl",
					{to_player=player_name, gain = 1.0})
			minetest.set_timeofday((21000 % 24000) / 24000)
			minetest.chat_send_player(player_name,
					S("Time of day set to 9pm"))
		else
			minetest.chat_send_player(player_name,
					S("You don't have the settime privilege!"))
			unified_inventory.set_inventory_formspec(player, unified_inventory.current_page[player_name])
		end
	end,
	condition = function(player)
		return minetest.check_player_privs(player:get_player_name(), {settime=true})
	end,
})

unified_inventory.register_button("clear_inv", {
	type = "image",
	image = "ui_trash_icon.png",
	tooltip = S("Clear inventory"),
	action = function(player)
		local player_name = player:get_player_name()
		if not unified_inventory.is_creative(player_name) then
			minetest.chat_send_player(player_name,
					S("This button has been disabled outside"
					.." of creative mode to prevent"
					.." accidental inventory trashing."
					.."\nUse the trash slot instead."))
			unified_inventory.set_inventory_formspec(player, unified_inventory.current_page[player_name])
			return
		end
		player:get_inventory():set_list("main", {})
		minetest.chat_send_player(player_name, S('Inventory cleared!'))
		minetest.sound_play("trash_all",
				{to_player=player_name, gain = 1.0})
	end,
	condition = function(player)
		return unified_inventory.is_creative(player:get_player_name())
	end,
})

unified_inventory.register_page("craft", {
	get_formspec = function(player, perplayer_formspec)

		local formspecy = perplayer_formspec.formspec_y
		local formheadery =  perplayer_formspec.form_header_y

		local player_name = player:get_player_name()
		local formspec = "background[2,"..formspecy..";6,3;ui_crafting_form.png]"
		formspec = formspec.."background[0,"..(formspecy + 3.5)..";8,4;ui_main_inventory.png]"
		formspec = formspec.."label[0,"..formheadery..";" ..F(S("Crafting")).."]"
		formspec = formspec.."listcolors[#00000000;#00000000]"
		formspec = formspec.."list[current_player;craftpreview;6,"..formspecy..";1,1;]"
		formspec = formspec.."list[current_player;craft;2,"..formspecy..";3,3;]"
		if unified_inventory.trash_enabled or unified_inventory.is_creative(player_name) or minetest.get_player_privs(player_name).give then
			formspec = formspec.."label[7,"..(formspecy + 1.5)..";" .. F(S("Trash:")) .. "]"
			formspec = formspec.."background[7,"..(formspecy + 2)..";1,1;ui_single_slot.png]"
			formspec = formspec.."list[detached:trash;main;7,"..(formspecy + 2)..";1,1;]"
		end
		formspec = formspec.."listring[current_name;craft]"
		formspec = formspec.."listring[current_player;main]"
		if unified_inventory.is_creative(player_name) then
			formspec = formspec.."label[0,"..(formspecy + 1.5)..";" .. F(S("Refill:")) .. "]"
			formspec = formspec.."list[detached:"..F(player_name).."refill;main;0,"..(formspecy +2)..";1,1;]"
		end
		return {formspec=formspec}
	end,
})

-- stack_image_button(): generate a form button displaying a stack of items
--
-- The specified item may be a group.  In that case, the group will be
-- represented by some item in the group, along with a flag indicating
-- that it's a group.  If the group contains only one item, it will be
-- treated as if that item had been specified directly.

local function stack_image_button(x, y, w, h, buttonname_prefix, item)
	local name = item:get_name()
	local count = item:get_count()
	local show_is_group = false
	local displayitem = name.." "..count
	local selectitem = name
	if name:sub(1, 6) == "group:" then
		local group_name = name:sub(7)
		local group_item = unified_inventory.get_group_item(group_name)
		show_is_group = not group_item.sole
		displayitem = group_item.item or "unknown"
		selectitem = group_item.sole and displayitem or name
	end
	local label = show_is_group and "G" or ""
	local buttonname = F(buttonname_prefix..unified_inventory.mangle_for_formspec(selectitem))
	local button = string.format("item_image_button[%f,%f;%f,%f;%s;%s;%s]",
			x, y, w, h,
			F(displayitem), buttonname, label)
	if show_is_group then
		local groupstring, andcount = unified_inventory.extract_groupnames(name)
		local grouptip
		if andcount == 1 then
			grouptip = string.format(S("Any item belonging to the %s group"), groupstring)
		elseif andcount > 1 then
			grouptip = string.format(S("Any item belonging to the groups %s"), groupstring)
		end
		grouptip = F(grouptip)
		if andcount >= 1 then
			button = button  .. string.format("tooltip[%s;%s]", buttonname, grouptip)
		end
	end
	return button
end

local recipe_text = {
	recipe = S("Recipe %d of %d"),
	usage = S("Usage %d of %d"),
}
local no_recipe_text = {
	recipe = S("No recipes"),
	usage = S("No usages"),
}
local role_text = {
	recipe = S("Result"),
	usage = S("Ingredient"),
}
local next_alt_text = {
	recipe = S("Show next recipe"),
	usage = S("Show next usage"),
}
local prev_alt_text = {
	recipe = S("Show previous recipe"),
	usage = S("Show previous usage"),
}
local other_dir = {
	recipe = "usage",
	usage = "recipe",
}

unified_inventory.register_page("craftguide", {
	get_formspec = function(player, perplayer_formspec)

		local formspecy =    perplayer_formspec.formspec_y
		local formheadery =  perplayer_formspec.form_header_y
		local craftresultx = perplayer_formspec.craft_result_x
		local craftresulty = perplayer_formspec.craft_result_y

		local player_name = player:get_player_name()
		local player_privs = minetest.get_player_privs(player_name)
		local fs = {
			"background[0,"..(formspecy + 3.5)..";8,4;ui_main_inventory.png]",
			"label[0,"..formheadery..";" .. F(S("Crafting Guide")) .. "]",
			"listcolors[#00000000;#00000000]"
		}
		local item_name = unified_inventory.current_item[player_name]
		if not item_name then
			return { formspec = table.concat(fs) }
		end

		local item_name_shown
		if minetest.registered_items[item_name]
				and minetest.registered_items[item_name].description then
			item_name_shown = string.format(S("%s (%s)"),
				minetest.registered_items[item_name].description, item_name)
		else
			item_name_shown = item_name
		end

		local dir = unified_inventory.current_craft_direction[player_name]
		local rdir = dir == "recipe" and "usage" or "recipe"

		local crafts = unified_inventory.crafts_for[dir][item_name]
		local alternate = unified_inventory.alternate[player_name]
		local alternates, craft
		if crafts and #crafts > 0 then
			alternates = #crafts
			craft = crafts[alternate]
		end
		local has_give = player_privs.give or unified_inventory.is_creative(player_name)

		fs[#fs + 1] = "background[0.5,"..(formspecy + 0.2)..";8,3;ui_craftguide_form.png]"
		fs[#fs + 1] = string.format("textarea[%f,%f;10,1;;%s: %s;]",
				craftresultx, craftresulty, F(role_text[dir]), item_name_shown)
		fs[#fs + 1] = stack_image_button(0, formspecy, 1.1, 1.1,
				"item_button_" .. rdir .. "_", ItemStack(item_name))

		if not craft then
			-- No craft recipes available for this item.
			fs[#fs + 1] = "label[5.5,"..(formspecy + 2.35)..";"
					.. F(no_recipe_text[dir]) .. "]"
			local no_pos = dir == "recipe" and 4.5 or 6.5
			local item_pos = dir == "recipe" and 6.5 or 4.5
			fs[#fs + 1] = "image["..no_pos..","..formspecy..";1.1,1.1;ui_no.png]"
			fs[#fs + 1] = stack_image_button(item_pos, formspecy, 1.1, 1.1,
				"item_button_" .. other_dir[dir] .. "_", ItemStack(item_name))
			if has_give then
				fs[#fs + 1] = "label[0," .. (formspecy + 2.10) .. ";" .. F(S("Give me:")) .. "]"
						.. "button[0,  " .. (formspecy + 2.7) .. ";0.6,0.5;craftguide_giveme_1;1]"
						.. "button[0.6," .. (formspecy + 2.7) .. ";0.7,0.5;craftguide_giveme_10;10]"
						.. "button[1.3," .. (formspecy + 2.7) .. ";0.8,0.5;craftguide_giveme_99;99]"
			end
			return { formspec = table.concat(fs) }
		end

		local craft_type = unified_inventory.registered_craft_types[craft.type] or
				unified_inventory.craft_type_defaults(craft.type, {})
		if craft_type.icon then
			fs[#fs + 1] = string.format("image[%f,%f;%f,%f;%s]",
					5.7, (formspecy + 0.05), 0.5, 0.5, craft_type.icon)
		end
		fs[#fs + 1] = "label[5.5,"..(formspecy + 1)..";" .. F(craft_type.description).."]"
		fs[#fs + 1] = stack_image_button(6.5, formspecy, 1.1, 1.1,
				"item_button_usage_", ItemStack(craft.output))

		local display_size = craft_type.dynamic_display_size
				and craft_type.dynamic_display_size(craft)
				or { width = craft_type.width, height = craft_type.height }
		local craft_width = craft_type.get_shaped_craft_width
				and craft_type.get_shaped_craft_width(craft)
				or display_size.width

		-- This keeps recipes aligned to the right,
		-- so that they're close to the arrow.
		local xoffset = 5.5
		-- Offset factor for crafting grids with side length > 4
		local of = (3/math.max(3, math.max(display_size.width, display_size.height)))
		local od = 0
		-- Minimum grid size at which size optimazation measures kick in
		local mini_craft_size = 6
		if display_size.width >= mini_craft_size then
			od = math.max(1, display_size.width - 2)
			xoffset = xoffset - 0.1
		end
		-- Size modifier factor
		local sf = math.min(1, of * (1.05 + 0.05*od))
		-- Button size
		local bsize_h = 1.1 * sf
		local bsize_w = bsize_h
		if display_size.width >= mini_craft_size then
			bsize_w = 1.175 * sf
		end
		if (bsize_h > 0.35 and display_size.width) then
		for y = 1, display_size.height do
		for x = 1, display_size.width do
			local item
			if craft and x <= craft_width then
				item = craft.items[(y-1) * craft_width + x]
			end
			-- Flipped x, used to build formspec buttons from right to left
			local fx = display_size.width - (x-1)
			-- x offset, y offset
			local xof = (fx-1) * of + of
			local yof = (y-1) * of + 1
			if item then
				fs[#fs + 1] = stack_image_button(
						xoffset - xof, formspecy - 1 + yof, bsize_w, bsize_h,
						"item_button_recipe_",
						ItemStack(item))
			else
				-- Fake buttons just to make grid
				fs[#fs + 1] = string.format("image_button[%f,%f;%f,%f;ui_blank_image.png;;]",
						xoffset - xof, formspecy - 1 + yof, bsize_w, bsize_h)
			end
		end
		end
		else
			-- Error
			fs[#fs + 1] = string.format("label[2,%f;%s]",
				formspecy, F(S("This recipe is too\nlarge to be displayed.")))
		end

		if craft_type.uses_crafting_grid and display_size.width <= 3 then
			fs[#fs + 1] = "label[0," .. (formspecy + 0.9) .. ";" .. F(S("To craft grid:")) .. "]"
					.. "button[0,  " .. (formspecy + 1.5) .. ";0.6,0.5;craftguide_craft_1;1]"
					.. "button[0.6," .. (formspecy + 1.5) .. ";0.7,0.5;craftguide_craft_10;10]"
					.. "button[1.3," .. (formspecy + 1.5) .. ";0.8,0.5;craftguide_craft_max;" .. F(S("All")) .. "]"
		end
		if has_give then
			fs[#fs + 1] = "label[0," .. (formspecy + 2.1) .. ";" .. F(S("Give me:")) .. "]"
					.. "button[0,  " .. (formspecy + 2.7) .. ";0.6,0.5;craftguide_giveme_1;1]"
					.. "button[0.6," .. (formspecy + 2.7) .. ";0.7,0.5;craftguide_giveme_10;10]"
					.. "button[1.3," .. (formspecy + 2.7) .. ";0.8,0.5;craftguide_giveme_99;99]"
		end

		if alternates and alternates > 1 then
			fs[#fs + 1] = "label[5.5," .. (formspecy + 1.6) .. ";"
					.. string.format(F(recipe_text[dir]), alternate, alternates) .. "]"
					.. "image_button[5.5," .. (formspecy + 2) .. ";1,1;ui_left_icon.png;alternate_prev;]"
					.. "image_button[6.5," .. (formspecy + 2) .. ";1,1;ui_right_icon.png;alternate;]"
					.. "tooltip[alternate_prev;" .. F(prev_alt_text[dir]) .. "]"
					.. "tooltip[alternate;" .. F(next_alt_text[dir]) .. "]"
		end
		return { formspec = table.concat(fs) }
	end,
})

local function craftguide_giveme(player, formname, fields)
	local player_name = player:get_player_name()
	local player_privs = minetest.get_player_privs(player_name)
	if not player_privs.give and
			not unified_inventory.is_creative(player_name) then
		minetest.log("action", "[unified_inventory] Denied give action to player " ..
			player_name)
		return
	end

	local amount
	for k, v in pairs(fields) do
		amount = k:match("craftguide_giveme_(.*)")
		if amount then break end
	end

	amount = tonumber(amount) or 0
	if amount == 0 then return end

	local output = unified_inventory.current_item[player_name]
	if (not output) or (output == "") then return end

	local player_inv = player:get_inventory()

	player_inv:add_item("main", {name = output, count = amount})
end

-- Takes any stack from "main" where the `amount` of `needed_item` may fit
-- into the given crafting stack (`craft_item`)
local function craftguide_move_stacks(inv, craft_item, needed_item, amount)
	if craft_item:get_count() >= amount then
		return
	end

	local get_item_group = minetest.get_item_group
	local group = needed_item:match("^group:(.+)")
	if group then
		if not craft_item:is_empty() then
			-- Source item must be the same to fill
			if get_item_group(craft_item:get_name(), group) ~= 0 then
				needed_item = craft_item:get_name()
			else
				-- TODO: Maybe swap unmatching "craft" items
				-- !! Would conflict with recursive function call
				return
			end
		else
			-- Take matching group from the inventory (biggest stack)
			local main = inv:get_list("main")
			local max_found = 0
			for i, stack in ipairs(main) do
				if stack:get_count() > max_found and
						get_item_group(stack:get_name(), group) ~= 0 then
					needed_item = stack:get_name()
					max_found = stack:get_count()
					if max_found >= amount then
						break
					end
				end
			end
		end
	else
		if not craft_item:is_empty() and
				craft_item:get_name() ~= needed_item then
			return -- Item must be identical
		end
	end

	needed_item = ItemStack(needed_item)
	local to_take = math.min(amount, needed_item:get_stack_max())
	to_take = to_take - craft_item:get_count()
	if to_take <= 0 then
		return -- Nothing to do
	end
	needed_item:set_count(to_take)

	local taken = inv:remove_item("main", needed_item)
	local leftover = taken:add_item(craft_item)
	if not leftover:is_empty() then
		-- Somehow failed to add the existing "craft" item. Undo the action.
		inv:add_item("main", leftover)
		return taken
	end
	return taken
end

local function craftguide_craft(player, formname, fields)
	local amount
	for k, v in pairs(fields) do
		amount = k:match("craftguide_craft_(.*)")
		if amount then break end
	end
	if not amount then return end

	amount = tonumber(amount) or 99 -- fallback for "all"
	if amount <= 0 or amount > 99 then return end

	local player_name = player:get_player_name()

	local output = unified_inventory.current_item[player_name] or ""
	if output == "" then return end

	local player_inv = player:get_inventory()
	local craft_list = player_inv:get_list("craft")

	local crafts = unified_inventory.crafts_for[
		unified_inventory.current_craft_direction[player_name]][output] or {}
	if #crafts == 0 then return end

	local alternate = unified_inventory.alternate[player_name]

	local craft = crafts[alternate]
	if craft.width > 3 then return end

	local needed = craft.items
	local width = craft.width
	if width == 0 then
		-- Shapeless recipe
		width = 3
	end

	-- To spread the items evenly
	local STEPSIZE = math.ceil(math.sqrt(amount) / 5) * 5
	local current_count = 0
	repeat
		current_count = math.min(current_count + STEPSIZE, amount)
		local index = 1
		for y = 1, 3 do
			for x = 1, width do
				local needed_item = needed[index]
				if needed_item then
					local craft_index = ((y - 1) * 3) + x
					local craft_item = craft_list[craft_index]
					local newitem = craftguide_move_stacks(player_inv,
							craft_item, needed_item, current_count)

					if newitem then
						craft_list[craft_index] = newitem
					end
				end
				index = index + 1
			end
		end
	until current_count == amount

	player_inv:set_list("craft", craft_list)

	unified_inventory.set_inventory_formspec(player, "craft")
end

minetest.register_on_player_receive_fields(function(player, formname, fields)
	if formname ~= "" then
		return
	end

	for k, v in pairs(fields) do
		if k:match("craftguide_craft_") then
			craftguide_craft(player, formname, fields)
			return
		end
		if k:match("craftguide_giveme_") then
			craftguide_giveme(player, formname, fields)
			return
		end
	end
end)