Update to work with Unified Inventory v2

i.e. the formspec v4 rewrite
Requires UI "version-2" tag or commit a7556c50 or later and
and Minetest v5.4.0 or later

This also makes it work properly in UI's "lite" mode.

formspecs.lua

@@ -1,4 +1,5 @@
 local S = minetest.get_translator("skinsdb")
+local ui = unified_inventory
 
 function skins.get_formspec_context(player)
 	if player then
@@ -11,7 +12,7 @@ function skins.get_formspec_context(player)
 end
 
 -- Show skin info
-function skins.get_skin_info_formspec(skin)
+function skins.get_skin_info_formspec(skin, perplayer_formspec)
 	local texture = skin:get_texture()
 	local m_name = skin:get_meta_string("name")
 	local m_author = skin:get_meta_string("author")
@@ -20,30 +21,82 @@ function skins.get_skin_info_formspec(skin)
 	-- overview page
 	local raw_size = m_format == "1.8" and "2,2" or "2,1"
 
-	local formspec = "image[0.8,.6;1,2;"..minetest.formspec_escape(skin:get_preview()).."]"
+	local lxoffs = 0.8
+	local cxoffs = 2
+	local rxoffs = 5.5
+
+	if type(perplayer_formspec) == "table" then -- we're using Unified Inventory
+		lxoffs = 1.5
+		cxoffs = 3.75
+		rxoffs = 7.5
+	end
+
+	local formspec = "image["..lxoffs..",.6;1,2;"..minetest.formspec_escape(skin:get_preview()).."]"
 	if texture then
-		formspec = formspec.."label[6,.5;"..S("Raw texture")..":]"
-		.."image[6,1;"..raw_size..";"..texture.."]"
+		formspec = formspec.."label["..rxoffs..",.5;"..S("Raw texture")..":]"
+		.."image["..rxoffs..",1;"..raw_size..";"..texture.."]"
 	end
 	if m_name ~= "" then
-		formspec = formspec.."label[2,.5;"..S("Name")..": "..minetest.formspec_escape(m_name).."]"
+		formspec = formspec.."label["..cxoffs..",.5;"..S("Name")..": "..minetest.formspec_escape(m_name).."]"
 	end
 	if m_author ~= "" then
-		formspec = formspec.."label[2,1;"..S("Author")..": "..minetest.formspec_escape(m_author).."]"
+		formspec = formspec.."label["..cxoffs..",1;"..S("Author")..": "..minetest.formspec_escape(m_author).."]"
 	end
 	if m_license ~= "" then
-		formspec = formspec.."label[2,1.5;"..S("License")..": "..minetest.formspec_escape(m_license).."]"
+		formspec = formspec.."label["..cxoffs..",1.5;"..S("License")..": "..minetest.formspec_escape(m_license).."]"
 	end
 	return formspec
 end
 
-function skins.get_skin_selection_formspec(player, context, y_delta)
+function skins.get_skin_selection_formspec(player, context, perplayer_formspec)
 	context.skins_list = skins.get_skinlist_for_player(player:get_player_name())
 	context.total_pages = 1
+	local xoffs = 0
+	local yoffs = 4
+	local xspc = 1
+	local yspc = 2
+	local skinwidth = 1
+	local skinheight = 2
+	local xscale = 1
+	local btn_y = 8.15
+	local drop_y = 8
+	local btn_width = 1
+	local droppos = 1
+	local droplen = 6.25
+	local btn_right = 7
+	local maxdisp = 16
+
+	local ctrls_height = 0.5
+
+	if type(perplayer_formspec) == "table" then -- it's being used under Unified Inventory
+		xoffs =  perplayer_formspec.std_inv_x
+		xspc =   ui.imgscale
+		yspc =   ui.imgscale*2
+		skinwidth =  ui.imgscale*0.9
+		skinheight = ui.imgscale*1.9
+		xscale = ui.imgscale
+		btn_width = ui.imgscale
+		droppos = xoffs + btn_width + 0.1
+		droplen = ui.imgscale * 6 - 0.2
+		btn_right = droppos + droplen + 0.1
+
+		if perplayer_formspec.pagecols == 4 then -- and we're in lite mode
+			yoffs =  1
+			maxdisp = 8
+			drop_y = yoffs + skinheight + 0.1
+		else
+			yoffs =  0.2
+			drop_y = yoffs + skinheight*2 + 0.2
+		end
+
+		btn_y = drop_y
+
+	end
+
 	for i, skin in ipairs(context.skins_list ) do
-		local page = math.floor((i-1) / 16)+1
+		local page = math.floor((i-1) / maxdisp)+1
 		skin:set_meta("inv_page", page)
-		skin:set_meta("inv_page_index", (i-1)%16+1)
+		skin:set_meta("inv_page_index", (i-1)%maxdisp+1)
 		context.total_pages = page
 	end
 	context.skins_page = context.skins_page or skins.get_player_skin(player):get_meta("inv_page") or 1
@@ -51,22 +104,25 @@ function skins.get_skin_selection_formspec(player, context, y_delta)
 
 	local page = context.skins_page
 	local formspec = ""
-	for i = (page-1)*16+1, page*16 do
+	
+	for i = (page-1)*maxdisp+1, page*maxdisp do
 		local skin = context.skins_list[i]
 		if not skin then
 			break
 		end
 
 		local index_p = skin:get_meta("inv_page_index")
-		local x = (index_p-1) % 8
+		local x = ((index_p-1) % 8) * xspc + xoffs
 		local y
 		if index_p > 8 then
-			y = y_delta + 1.9
+			y = yoffs + yspc
 		else
-			y = y_delta
+			y = yoffs
 		end
-		formspec = formspec.."image_button["..x..","..y..";1,2;"..
-			minetest.formspec_escape(skin:get_preview())..";skins_set$"..i..";]"..
+		formspec = formspec..
+			string.format("image_button[%f,%f;%f,%f;%s;skins_set$%i;]",
+				x, y, skinwidth, skinheight,
+				minetest.formspec_escape(skin:get_preview()), i)..
 			"tooltip[skins_set$"..i..";"..minetest.formspec_escape(skin:get_meta_string("name")).."]"
 	end
 
@@ -87,10 +143,13 @@ function skins.get_skin_selection_formspec(player, context, y_delta)
 			if pg > 1 then page_list = page_list.."," end
 			page_list = page_list..pagename
 		end
-		formspec = formspec
-			.."button[0,"..(y_delta+4.0)..";1,.5;skins_page$"..page_prev..";<<]"
-			.."dropdown[0.9,"..(y_delta+3.88)..";6.5,.5;skins_selpg;"..page_list..";"..page.."]"
-			.."button[7,"..(y_delta+4.0)..";1,.5;skins_page$"..page_next..";>>]"
+		formspec = formspec..
+			string.format("button[%f,%f;%f,%f;skins_page$%i;<<]",
+				xoffs, btn_y, btn_width, ctrls_height, page_prev)..
+			string.format("button[%f,%f;%f,%f;skins_page$%i;>>]",
+				btn_right, btn_y, btn_width, ctrls_height, page_next)..
+			string.format("dropdown[%f,%f;%f,%f;skins_selpg;%s;%i]",
+				droppos, drop_y, droplen, ctrls_height, page_list, page)
 	end
 	return formspec
 end

mod.conf

@@ -2,3 +2,4 @@ name = skinsdb
 description = Player skin mod, supporting unified_inventory, sfinv and smart_inventory
 depends = player_api
 optional_depends = unified_inventory,3d_armor,clothing,sfinv
+min_minetest_version = 5.4.0

unified_inventory_page.lua

@@ -1,10 +1,13 @@
 local S = minetest.get_translator("skinsdb")
 
 unified_inventory.register_page("skins", {
-	get_formspec = function(player)
+	get_formspec = function(player, perplayer_formspec)
 		local skin = skins.get_player_skin(player)
-		local formspec = "background[0.06,0.99;7.92,7.52;ui_misc_form.png]"..skins.get_skin_info_formspec(skin)..
-				"button[.75,3;6.5,.5;skins_page;"..S("Change").."]"
+		local boffs = (type(perplayer_formspec) == "table") and 2 or 0.75
+
+		local formspec = perplayer_formspec.standard_inv_bg..
+			skins.get_skin_info_formspec(skin, perplayer_formspec)..
+			"button["..boffs..",3;6.5,.5;skins_page;"..S("Change").."]"
 		return {formspec=formspec}
 	end,
 })
@@ -15,16 +18,16 @@ unified_inventory.register_button("skins", {
 	tooltip = S("Skins"),
 })
 
-local function get_formspec(player)
+local function get_formspec(player, perplayer_formspec)
 	local context = skins.get_formspec_context(player)
-	local formspec = "background[0.06,0.99;7.92,7.52;ui_misc_form.png]"..
-			skins.get_skin_selection_formspec(player, context, -0.2)
+	local formspec = perplayer_formspec.standard_inv_bg..
+			skins.get_skin_selection_formspec(player, context, perplayer_formspec)
 	return formspec
 end
 
 unified_inventory.register_page("skins_page", {
-	get_formspec = function(player)
-		return {formspec=get_formspec(player)}
+	get_formspec = function(player, perplayer_formspec)
+		return {formspec=get_formspec(player, perplayer_formspec)}
 	end
 })