gamedata = {
    
}

local http = minetest.get_http_api()

-- Used for brevity when making fullscreen things
window = minetest.get_window_info()
size = window.max_formspec_size

-- Default textures
default_textures = minetest.get_texturepath_share().."/base/pack/"

--FIXME: Assets
local assets = "/Users/iboettcher/eclipse-workspace/mods/mtmenu/"

local version = minetest.get_version()

-- Holds all the interface parts
state = {}

local fe = minetest.formspec_escape
local hte = minetest.hypertext_escape

---[[

-- Prepended to the meta menu's formspec.
local meta_header = "formspec_version[8]\
        size["..size.x..","..size.y.."]\
        padding[0,0]\
        style[*;textcolor=#aaa]\
        style_type[image_button;border=false]\
        style_type[button;border=false;bgimg="..assets.."btn_bg.png;bgimg_middle=8,8]\
        bgcolor[#000;true;#151618]\
        style_type[box;bordercolors=#124722;borderwidths=-5;colors=#151618]\
        box[0,0;"..size.x..","..size.y..";]\
        image[0,"..(size.y *0.08)..");"..size.x..","..(size.x *(72/672))..";"..default_textures.."menu_header.png]\
        "
local meta_footer = "\
        style[nobg;border=false;bgimg="..default_textures.."blank.png;bgimg_middle=0]\
        style[show_servers_view;border=false;bgimg="..fe(assets).."menu_servers.png;bgimg_middle=0]\
        style[show_servers_view:hovered;border=false;bgimg="..fe(assets).."menu_servers_hovered.png;bgimg_middle=0]\
        button["..(size.x *0.05)..","..(size.y *0.3)..";4,4;show_servers_view;]\
        button["..(size.x *0.05)..","..(size.y *0.3 +4)..";4,0.5;nobg;Servers]\
        style[show_content_view;border=false;bgimg="..fe(assets).."menu_content.png;bgimg_middle=0]\
        style[show_content_view:hovered;border=false;bgimg="..fe(assets).."menu_content_hovered.png;bgimg_middle=0]\
        button["..(size.x -(size.x *0.05) -4)..","..(size.y *0.3)..";4,4;show_content_view;]\
        button["..(size.x -(size.x *0.05) -4)..","..(size.y *0.3 +4)..";4,0.5;nobg;Content]\
        "

-- Prepended to game menus' formspecs.
local game_header = "formspec_version[8]\
        size["..size.x..","..size.y.."]\
        padding[0,0]\
        style[*;textcolor=#aaa]\
        style_type[image_button;border=false]\
        style_type[button;border=false;bgimg="..assets.."btn_bg.png;bgimg_middle=8,8]\
        bgcolor[#0000;true;#0000]\
        "
local servers_header = "formspec_version[8]\
        size["..size.x..","..size.y.."]\
        padding[0,0]\
        style[*;textcolor=#aaa]\
        style_type[image_button;border=false]\
        style_type[field;border=false]\
        style_type[pwdfield;border=false]\
        style_type[button;border=false;bgimg="..assets.."btn_bg_2.png;bgimg_middle=8,8]\
        style_type[button:hovered;border=false;bgimg="..assets.."btn_bg_2_hover.png;bgimg_middle=8,8]\
        bgcolor[#0000;true;#151618]\
        "

local content_header = "formspec_version[8]\
        size["..size.x..","..size.y.."]\
        padding[0,0]\
        style[*;textcolor=#aaa]\
        style_type[image_button;border=false]\
        style_type[button;border=false;bgimg="..assets.."btn_bg.png;bgimg_middle=8,8]\
        bgcolor[#0000;true;#151618]\
        "

-- The default main menu for games.
local default_game_menu = [[
<meta>
    enable_clouds = true
</meta>
<main>
@set:test:Hello
    label[2,2;Test]
    scroll_container[1,6;4,2;worldscroll;vertical;;0,0]
    @foreach:$WORLDS:worlds
      @if:@i % 2:sel
        style[.select_world_${@name};bgimg=$DEFAULT_ASSET_PATH/white.png;bgimg_middle=0;bgcolor=#373530]
        style[.select_world_${@name}:hovered;bgimg=$DEFAULT_ASSET_PATH/white.png;bgimg_middle=0;bgcolor=#373530]
        style[.select_world_${@name}:hovered+focused;bgimg=$DEFAULT_ASSET_PATH/white.png;bgimg_middle=0;bgcolor=#373530]
      @else:sel
        style[.select_world_${@name};bgimg=$DEFAULT_ASSET_PATH/white.png;bgimg_middle=0;bgcolor=#403e39]
        style[.select_world_${@name}:hovered;bgimg=$DEFAULT_ASSET_PATH/white.png;bgimg_middle=0;bgcolor=#403e39]
        style[.select_world_${@name}:hovered+focused;bgimg=$DEFAULT_ASSET_PATH/white.png;bgimg_middle=0;bgcolor=#403e39]
      @endif:sel
      button[0,${@i * 0.5};4,0.5;.select_world_${@name};${@test}]
    @endforeach:worlds
    scroll_container_end[]
    scrollbaroptions[arrows=hide]
    scrollbar[-800,6;0,2;vertical;worldscroll;]
</main>
<addworld>
    label[2,2;Add World, asset path is $ASSET_PATH]
    button[2,3;3,1;.show_dialog_main;back]
    
    @foreach:[hello,there,bob]:myloop
      label[6,${@i + 3};${@item}]
    @endforeach:myloop
</addworld>
]]
          
function core.on_before_close()
    --minetest.settings:write()
end


minetest.async_jobs = {}

local function handle_job(jobid, serialized_retval)
    local retval = minetest.deserialize(serialized_retval)
    assert(type(minetest.async_jobs[jobid]) == "function")
    minetest.async_jobs[jobid](retval)
    minetest.async_jobs[jobid] = nil
end

minetest.async_event_handler = handle_job

function minetest.handle_async(func, parameter, callback)
    -- Serialize function
    local serialized_func = string.dump(func)

    assert(serialized_func ~= nil)

    -- Serialize parameters
    local serialized_param = minetest.serialize(parameter)

    if serialized_param == nil then
        return false
    end

    local jobid = minetest.do_async_callback(serialized_func, serialized_param)

    minetest.async_jobs[jobid] = callback

    return true
end


-- MARK: - Helpers

-- Returns the contents of the file, or nil in case of failure.
local function read_file(path)
    local f = io.open(path)
    if f then
        local data = f:read("a")
        f:close()
        if data == "" then return end
        return data
    end
end

-- Check if a file exists.
local function file_exists(path)
    local f = io.open(path)
    if f then
        f:close()
        return true
    end
    return false
end

-- Returns the get_games() entry corresponding to a given game ID.
local function get_game_info(game)
    for _, x in ipairs(minetest.get_games()) do
        if x.id == game then
            return x
        end
    end
end

local function get_worlds_for_game(id)
    local out = {}
    for _, x in ipairs(minetest.get_worlds()) do
        if x.gameid == id then
            if math.random() > 0.5 then x.selected = true end
            out[#out +1] = x
        end
    end
    return out
end

-- Returns a list of content available for download.
function get_all_content()
    local version = minetest.get_version()
    local cdb = minetest.settings:get("contentdb_url")
    local url = cdb.."/api/packages/?type=mod&type=game&type=txp&protocol_version="..minetest.get_max_supp_proto().."&engine_version="..minetest.urlencode(version.string)
    
    for _, x in pairs(minetest.settings:get("contentdb_flag_blacklist"):split(",")) do
        x = x:trim()
        if x ~= "" then
            url = url.."&hide="..minetest.urlencode(x)
        end
    end

    local languages
    local lang = minetest.get_language()
    if lang ~= "" then
        languages = { lang, "en;q=0.8" }
    else
        languages = { "en" }
    end

    local http = minetest.get_http_api()
    local response = http.fetch_sync({
        url = url,
        extra_headers = {
            "Accept-Language: "..table.concat(languages, ", ")
        },
    })
    if not response.succeeded then
        return
    end
    local items = minetest.parse_json(response.data)
    local out = {}
    for _, x in pairs(items) do
        out[#out +1] = x
    end
    return out
end

-- Parses text as .conf format.
function parse_conf_text(txt)
    local out = {}
    local multiline = false
    local key = ""
    local value = ""
    for line in (txt.."\n"):gmatch("(.*)\n") do
        if multiline then
            if line:find("\"\"\"") then
                line = line:gsub("\"\"\"", ""):trim()
                multiline = false
                out[key] = value.."\n"..line
                key = ""
                value = ""
            else
                value = value.."\n"..line:trim()
            end
        else
            local k, v = line:match("(.-)=(.*)")
            if not k then break end
            if v:find("\"\"\"") then
                key = k:trim()
                value = v:gsub("\"\"\"", ""):trim()
                multiline = true
            else
                out[k:trim()] = v:trim()
            end
        end
    end
    return out
end

--[[ MARK: - Template Engine
    
Builds a formspec from the contents of a game-provided main menu file.

=================================================================================
                            Menu File Documentation
=================================================================================

Menu files are essentially just formspecs, but with special semantics and extended syntax.

First, menu files are made up of a number of dialog definitions. A dialog definition is
basically an HTML tag, where the tag name is the name of the dialog. For example this:
```
<main>
  label[2,2;A label]
</main>
<other>
  button[1,1;4,1;button;This is a button]
</other>
```
will define a dialog named 'main', with a label in it, and a dialog named 'other',
with a button in it. Every menu file must have a dialog named 'main', which serves
as the entry point of the game's menu.

Being able to define these other dialogs would be pretty pointless if they couldn't
be used for anything. Accordingly, you can use standard formspec actions, e.g. buttons,
to segue to a different dialog. To do this, set the action name to
'.show_dialog_<name>', where <name> is the name of the dialog you want to open.
You can also use '.overlay_dialog_<name>' to draw the target dialog on top of the
current dialog, and '.unoverlay_dialog' to hide it again.

There are several other action patterns that invoke special behavior:
  - 
  - '.play': Start the game.
  - '.play_with_world_named_<name>': Start the game on the specified world. If the
    world in question does not exist, it will be created.

It is also possible to define metadata for the main menu. To do this, create a dialog
section named 'meta'. The contents of this section will then be parsed in the same way
as minetest.conf instead of being treated as a dialog.

Available metadata options are:
  - 'enable_clouds': true/false (defaults to false)


Now, all this is good when we know exactly what content we want on the main menu.
But what if we want to render e.g. a list of worlds, or even a list of game modes?
This can be done using the @foreach construct. @foreach takes in a list of values,
the name of a JSON file, or a reference to a menu-exposed list.

The major advantage of a foreach loop, however, is interpolation. Inside a foreach
loop, the pattern '${<expression>}' will be replaces with the result of <expression>.

Inside an expression, you can reference variables as '@<name>'. Which variables are
available depends on the iterated list. In the case of a list literal, the current
item is exposed as a variable named @item, while for a JSON file, each key in the
file's top-level object will correspond to a variable. (Note that variable names may
only contain letters or numbers, even if mapped from a JSON file.)

The menu-provided lists are:
  - $WORLDS: The list of worlds for this game. Exposes @name (the world name),
    @path (the world's full absolute path), @gameid (the ID of the current game),
    and @selected (whether the world is currently selected).

Expressions also support rudimentary mathematical operations, namely addition (+),
subtraction (+-), multiplication (*), division (/), and exponentiation (^). Trying
to perform math on a non-tonumber()-able variable will treat the variable as 0.
Grouping is not supported (yet).

As an example, this:
```
label[1,1;Worlds:]
@foreach:$WORLDS:name
  label[1,${@i + 1};World named ${@name}]
@endforeach:name

@foreach:[one,two,three]:name2
  label[4,${@i + 1};Item ${@i} is named: ${@item}]
@endforeach:name2
```
will:
  - Create a "Worlds" label at 1,1;
  - Create a label for every world with that world's name and a Y coordinate that
    corresponds to the world's position in the list, plus 1 so these labels start
    below the existing label.
  - Create labels for "one", "two", and "three" that display the item's value and
    its position in the list, with similarly increasing Y-coordinates.

Besides foreach loops, menu files also support conditionals. Conditionals are
written as '@if:<condition>:<name> ... @else:<name> ... @endif:<name>', where
<condition> is any expression. The conditional will be replaced with the contents
of its first block if the condition evaluates to non-zero, and the contents of
its second block otherwise.

Example:
```
@if: @name = test :<name>
  <formspec 1>
@else:<name>
  <formspec 2>
@endif:<name>
```
    
Note: Because of the way the main menu works, image paths must be specified in full.
To make this non-painful, when referencing images use '$ASSET_PATH/<image name>'
instead of just the image name. $ASSET_PATH will be replaced with the actual path
to the game's menu/ directory, so images used by the main menu should be stored
there. You can use $ASSET_PATH in any context. Additionally, $DEFAULT_ASSET_PATH is
the path to the builtin assets folder, and $NO_IMAGE is the path to blank.png, in
case you need to stylistically unset a background image defined by a global style.
--]]
local function build_template_dialog(fs)
    if fs:trim() == "" then return end
    local dialog = {}
    local i = 0
    -- "(.-\n?)%s-@foreach:([^:]+):(%l*)\n(.-)\n%s-@endforeach:%3(\n?.*)"
    -- Extract foreach loops
    local prev = 1
    while i < 1000 do
        local a, b, pattern, name, content = fs:find("@foreach:([^:]+):(%w*)\n(.-)\n%s-@endforeach:%2", prev)
        if not a then break end
--        print("for each "..pattern.." ("..name..")\n"..content.."\nend for each ("..name..")")
        dialog[#dialog +1] = build_template_dialog(fs:sub(prev +1, a -1))
        dialog[#dialog +1] = {
            foreach = pattern:trim(),
            name = name,
            content = build_template_dialog(content:trim())
        }
        prev = b
        i = i +1
    end
    
    if i > 0 then
        dialog[#dialog +1] = build_template_dialog(fs:sub(prev +1))
    else
        -- Extract conditionals
        prev = 0
        while i < 1000 do
            local a, b, expr, name, content, else_content = fs:find("@if:([^:]+):(%w*)\n(.-)\n%s-@else:%2\n(.-\n?)@endif:%2", prev)
            if not a then break end
    --        print("for each "..pattern.." ("..name..")\n"..content.."\nend for each ("..name..")")
            dialog[#dialog +1] = fs:sub(prev +1, a -1)
            dialog[#dialog +1] = {
                condition = expr:trim(),
                name = name,
                content = build_template_dialog(content:trim()),
                else_content = build_template_dialog(else_content:trim())
            }
            prev = b
            i = i +1
        end
        if i > 0 then
            dialog[#dialog +1] = fs:sub(prev +1)
        end
    end

    if #dialog == 1 then dialog = dialog[1] end
    if i == 0 then dialog = fs end
--    minetest.log(dump(dialog, "  "))
    return dialog
end

local function build_game_menu(input)
    -- MARK: Environment variables
    input = input
        :gsub("%$ASSET_PATH", fe(state.current_game.path.."/menu"))
        :gsub("%$DEFAULT_ASSET_PATH", fe(assets:sub(1, #assets -1)))
        :gsub("%$NO_IMAGE", fe(default_textures.."blank.png"))
        :gsub("/%*.-%*/", "")
    local menu = {}
    for name, fs in input:gmatch("<(%l+)>(.-)</%1>") do
        if name == "meta" then
            menu[name] = parse_conf_text(fs)
        else
            menu[name] = build_template_dialog(fs)
        end
    end
    return menu
end


-- Split a template expression into a binary-tree node.
local function split_template_expression(expr)
    
    -- These are basically the operator definitions, listed from lowest
    -- (evaluated last) to highest (evaluated first) precedence.
    
    local a, b, op
    -- Or
    if not a then
        a, b, op = expr:find("(|)")
    end
    -- And
    if not a then
        a, b, op = expr:find("(&)")
    end
    -- Greater than
    if not a then
        a, b, op = expr:find("(>)")
    end
    -- Greater than or equal to
    if not a then
        a, b, op = expr:find("(>=)")
    end
    -- Less than
    if not a then
        a, b, op = expr:find("(<)")
    end
    -- Less than or equal to
    if not a then
        a, b, op = expr:find("(<=)")
    end
    -- Equal to
    if not a then
        a, b, op = expr:find("(==)")
    end
    if not a then
        a, b, op = expr:find("(=)")
    end
    
    -- Addition
    if not a then
        a, b, op = expr:find("(+)")
    end
    -- Multiplication
    if not a then
        a, b, op = expr:find("(*)")
    end
    -- Division
    if not a then
        a, b, op = expr:find("(/)")
    end
    -- Modulo
    if not a then
        a, b, op = expr:find("(%%)")
    end
    -- Exponent
    if not a then
        a, b, op = expr:find("(%^)")
    end
    
    if not a then
        return {value = expr}
    end
    
    return {
        op = op,
        lhs = split_template_expression(expr:sub(1, a -1)),
        rhs = split_template_expression(expr:sub(b +1))
    }
end

-- Reduce a template expression from a binary-tree node into a single value.
local function reduce_template_expression(tree)
    if tree.op == "|" then
        return (reduce_template_expression(tree.lhs) ~= "0" or reduce_template_expression(tree.rhs) ~= "0") and "1" or "0"
    elseif tree.op == "&" then
        return (reduce_template_expression(tree.lhs) ~= "0" and reduce_template_expression(tree.rhs) ~= "0") and "1" or "0"
    elseif tree.op == ">" then
        return (tonumber(reduce_template_expression(tree.lhs)) or 0) > (tonumber(reduce_template_expression(tree.rhs)) or 0) and "1" or "0"
    elseif tree.op == ">=" then
        return (tonumber(reduce_template_expression(tree.lhs)) or 0) >= (tonumber(reduce_template_expression(tree.rhs)) or 0) and "1" or "0"
    elseif tree.op == "<" then
        return (tonumber(reduce_template_expression(tree.lhs)) or 0) < (tonumber(reduce_template_expression(tree.rhs)) or 0) and "1" or "0"
    elseif tree.op == "<=" then
        return (tonumber(reduce_template_expression(tree.lhs)) or 0) <= (tonumber(reduce_template_expression(tree.rhs)) or 0) and "1" or "0"
    elseif tree.op == "=" or tree.op == "==" then
        return (tonumber(reduce_template_expression(tree.lhs)) or 0) == (tonumber(reduce_template_expression(tree.rhs)) or 0) and "1" or "0"
    elseif tree.op == "+" then
        return (tonumber(reduce_template_expression(tree.lhs)) or 0) + (tonumber(reduce_template_expression(tree.rhs)) or 0)
    elseif tree.op == "*" then
        return (tonumber(reduce_template_expression(tree.lhs)) or 0) * (tonumber(reduce_template_expression(tree.rhs)) or 0)
    elseif tree.op == "/" then
        return (tonumber(reduce_template_expression(tree.lhs)) or 0) / (tonumber(reduce_template_expression(tree.rhs)) or 0)
    elseif tree.op == "%" then
        return (tonumber(reduce_template_expression(tree.lhs)) or 0) % (tonumber(reduce_template_expression(tree.rhs)) or 0)
    elseif tree.op == "^" then
        return (tonumber(reduce_template_expression(tree.lhs)) or 0) ^ (tonumber(reduce_template_expression(tree.rhs)) or 0)
    else
        return tree.value
    end
end

-- Evaluate an interpolation expression, with an optional table of variables.
local function evaluate_template_expression(expr, vars, depth)
    if expr == "" then return "0" end
    if not depth then depth = 0 end
    -- This handles the case where vars is omitted, because then it ends up
    -- just setting vars to an empty table.
    if type(vars) ~= "table" then
        vars = {item = vars}
    end
    
    -- Expand all variables so we can deal with a constexpr
    local offset = 1
    while offset < 100000 do
        local a, b, name = expr:find("@([%a]+)", offset)
        if not a then break end
        -- If referencing an undefined variable, default to 0 because it's safest that way.
        local result = minetest.formspec_escape(tostring(vars[name] or "0"))
        expr = expr:sub(1, a -1)..result..expr:sub(b +1)
        offset = a +#result
    end
    -- If there are no operators, this is a constant expression and we can just return.
    if not expr:find("%p") then return expr end
    
    -- Expression parsing
    local tree = split_template_expression(expr)
    return tostring(reduce_template_expression(tree))
end

-- Do variable interpolation for the given formspec using the provided variable table.
local function evaluate_template_block(fs, vars)
    -- Assignment statements
    local offset = 1
    while offset < #fs do
        local a, b, name, expr = fs:find("@set:(%w+):(.-)\n", offset)
        if not a then break end
        vars[name] = evaluate_template_expression(expr, vars)
        fs = fs:sub(1, a -1)..fs:sub(b +1)
        offset = a
    end
    -- Interpolations
    offset = 1
    while offset < #fs do
        local a, b, expr = fs:find("%${([^}]-)}", offset)
        if not a then break end
        local result = evaluate_template_expression(expr, vars)
        fs = fs:sub(1, a -1)..result..fs:sub(b +1)
        offset = a +#result
    end
    return fs
end

-- Interpret the list expression of a foreach loop, then iterate.
local function evaluate_template_foreach(loop, vars)
    local out = ""
    local list = {}
    if loop.foreach:sub(1,1) == "[" then
        list = loop.foreach:gsub("^%[(.*)%]$", "%1"):split(",")
    elseif loop.foreach == "$WORLDS" then
        list = get_worlds_for_game(state.current_game.id)
    end
    for i, x in ipairs(list) do
        local vars2 = {}
        if type(x) ~= "table" then
            vars2.item = x
        else
            for k, v in pairs(x) do
                vars2[k] = v
            end
        end
        vars.i = i
        out = out..evaluate_game_dialog(loop.content, setmetatable(vars2, {__index = vars, __newindex = vars})).."\n"
    end
    return out
end

-- Determine which branch of an if statement should be evaluated.
local function evaluate_template_conditional(cond, vars)
    local out = ""
    local list = {}
    local condition = evaluate_template_expression(cond.condition, vars)
    if condition ~= "0" then
        out = out..evaluate_game_dialog(cond.content, vars).."\n"
    else
        out = out..evaluate_game_dialog(cond.else_content, vars).."\n"
    end
    return out
end

-- Game dialogs might contain e.g. foreach loops, so build those if needed.
function evaluate_game_dialog(dialog, vars)
    local out = ""
    if type(dialog) == "string" then return evaluate_template_block(dialog, vars) end
    for _, x in ipairs(dialog) do
        if type(x) == "string" then
            out = out..evaluate_template_block(x, vars)
        elseif x.condition then
            out = out..evaluate_template_conditional(x, vars)
        elseif x.foreach then
            out = out..evaluate_template_foreach(x, vars)
        else
            for _, c in ipairs(x) do
                out = out..evaluate_game_dialog(c, vars)
            end
        end
    end
    return out
end

-- MARK: - Views

-- The meta menu, for choosing which game menu to enter or entering the servers/content views.
local last_game = minetest.settings:get("menu_last_game")
function show_meta_menu(v)
    state.loc = "games"
    local games = minetest.get_games()
    if #games < 1 then
        minetest.update_formspec(meta_header.."\
        hypertext[0,0;"..size.x..","..size.y..";ht;<global valign=middle halign=center><tag name=action color=#222 hovercolor=#444>\
            <style size=72 color=#222><b>No games installed.</b></style>\
            <style size=36 color=#222><action name=content>Click here to install a game.</action></style>]\
        ")
        return
    end
    local idx = 1
    for i, x in ipairs(games) do
        if x.id == last_game then idx = i end
    end
    if v then idx = v else v = idx end
    local fs = ""
    
    
    fs = fs.."\
    scroll_container[0,0;"..size.x..","..size.y..";carousel;horizontal;;]\
    box[0,0;"..(#games *5)..",1;#0000]\
    "

    
    local center = (size.x /2) +(v /10)
        
    for i, x in ipairs(games) do
        fs = fs.."\
        image_button["..(center +(i -(#games /2)) *0.25)..","..(size.y -0.5)..";0.25,0.25;"..assets..(i == idx and "circle_light" or "circle")..".png;jump"..i..";]\
        "
        
        local dist = i -idx
        local scale = 4 /(math.abs(dist) +1)
        if scale > 0.1 then
            --This looks cool, but is useless for UI purposes: center +10^(1 /math.abs(dist)) *math.sign(dist)
            local lc = center +math.abs(dist *10)^0.55 *math.sign(dist)
            local test = io.open(x.menuicon_path)
            if test then
                test:close()
            else
                x.menuicon_path = assets.."games.png"
            end
            --TODO: Do these need some kind of background?
            fs = fs.."\
                image_button["..(lc -(scale /2))..","..(size.y /2 -(scale /2) +(4 -scale) /2 +2)..";"..scale..","..scale..";"..fe(x.menuicon_path)..";game"..fe(x.id)..";]\
                tooltip[game"..fe(x.id)..";"..fe(x.title)..";#444;#aaa]\
                "
            if dist == 0 then
                fs = fs.."\
                style[_game_label;bgimg="..default_textures.."blank.png]\
                button["..(lc -(scale /2))..","..(size.y /2 +4)..";4,0.5;_game_label;"..fe(x.title).."]\
                "
            end
        end
    end
    
    
    fs = fs.."\
    scroll_container_end[]\
    scrollbaroptions[min=1;max="..#games..";smallstep=1]\
    scrollbar[0,-800;"..size.x..",0;horizontal;carousel;"..(v or "").."]\
    "
    
    minetest.update_formspec(meta_header..fs..meta_footer)
end

-- Shows games' custom menus.
function show_game_menu(args)
    if not state.current_game then
        minetest.log("warning", "Main menu attempted to show a menu for a nonexistent game; aborting.")
        return
    end
    if not args then args = {} end
    local game = state.current_game
    if not game.menu then
        local file = read_file(game.path.."/menu/mainmenu.txt") or default_game_menu
        
        local overlays = {}
        local backgrounds = {}
        local headers = {}
        local footers = {}
        local music = {}
        
        for _, x in ipairs(minetest.get_dir_list(game.path.."/menu", false)) do
            if x:sub(1, string.len("background")) == "background" then
                local a, b, id = x:find("background.(%d+).png")
                if a or x == "background.png" then
                    backgrounds[(tonumber(id) or 0) +1] = x
                end
            elseif x:sub(1, string.len("overlay")) == "overlay" then
                local a, b, id = x:find("overlay.(%d+).png")
                if a or x == "overlay.png" then
                    overlays[(tonumber(id) or 0) +1] = x
                end
            elseif x:sub(1, string.len("header")) == "header" then
                local a, b, id = x:find("header.(%d+).png")
                if a or x == "header.png" then
                    headers[(tonumber(id) or 0) +1] = x
                end
            elseif x:sub(1, string.len("footer")) == "footer" then
                local a, b, id = x:find("footer.(%d+).png")
                if a or x == "footer.png" then
                    footers[(tonumber(id) or 0) +1] = x
                end
            elseif x:sub(1, string.len("theme")) == "theme" then
                local a, b, id = x:find("theme.(%d+).ogg")
                if a or x == "theme.ogg" then
                    music[(tonumber(id) or 0) +1] = x
                end
            end
        end
                
        if #backgrounds > 0 then
            local path = game.path.."/menu/"..backgrounds[math.random(#backgrounds)]
            if minetest.set_background("background", path) then
                game.background = path
            end
        elseif #overlays > 0 then
            local path = game.path.."/menu/"..overlays[math.random(#overlays)]
            -- I don't know why, but using "overlay" here simply does nothing. Whatever
            -- the difference is, it isn't visual, so this effectively 'fixes' it.
            if minetest.set_background("background", path) then
                game.overlay = path
            end
        else
            minetest.set_background("background", "")
        end

        if #headers > 0 then
            local path = game.path.."/menu/"..headers[math.random(#headers)]
            if minetest.set_background("header", path) then
                game.header = path
            end
        end
        
        game.menu = build_game_menu(file)
    end
    
    if args.show_dialog then
        state.menu_current = {args.show_dialog}
    elseif args.overlay_dialog then
        state.menu_current[#state.menu_current +1] = args.overlay_dialog
    elseif args.unoverlay_dialog and #state.menu_current > 1 then
        state.menu_current[#state.menu_current] = nil
    end
    
    local fs = ""
    
    if not game.background and not game.overlay then
        fs = "\
        bgcolor[#000;true;#151618]\
        "
    end
    
    for i, x in ipairs(state.menu_current) do
        fs = fs..evaluate_game_dialog(game.menu[x], setmetatable({WIDTH = size.x, HEIGHT = size.y}, {__index = state.menu_vars}))
    end
    
    minetest.update_formspec(game_header..fs.."\
    button[0,"..(size.y -1)..";1,1;to_meta_menu;<]\
    ")
end


function refresh_server_list()
    minetest.handle_async(
        function(param)
            local http = minetest.get_http_api()
            local url = ("%s/list?proto_version_min=%d&proto_version_max=%d"):format(
                "https://servers.luanti.org" or minetest.settings:get("serverlist_url"),
                minetest.get_min_supp_proto(),
                minetest.get_max_supp_proto())

            local response = http.fetch_sync({ url = url })
            if not response.succeeded then
                return {}
            end

            local retval = minetest.parse_json(response.data)
            return retval and retval.list or {}
        end,
        nil,
        function(result)
            state.serverlist = result
            -- If we need to load the server list, we need to read the list of favorite servers as well.
            local favorite_servers = minetest.parse_json(read_file(minetest.get_user_path().."/client/serverlist/favoriteservers.json") or "{}")
            if #favorite_servers > 0 then
                for _, x in ipairs(favorite_servers) do
                    x.favorite = true
                end
                table.insert_all(favorite_servers, state.serverlist)
                state.serverlist = favorite_servers
            end
            state.favorite_servers = favorite_servers
            if state.loc == "servers" then
                show_servers_menu()
            end
        end
    )
end

-- Shows the server list.
function show_servers_menu()
    local fs = ""
    local loading
    if not state.serverlist then
        loading = true
        refresh_server_list()
        local favorite_servers = minetest.parse_json(read_file(minetest.get_user_path().."/client/serverlist/favoriteservers.json") or "{}")
        for _, x in ipairs(favorite_servers) do
            x.favorite = true
        end
        state.serverlist = favorite_servers
--        fs = "\
--        hypertext[0,0;"..size.x..","..size.y..";ht;<global valign=middle halign=center><tag name=action color=#222 hovercolor=#444>\
--            <style size=72 color=#222><b>Fetching server list...</b></style>]\
--        "
    end
    local current_server
    local joining_server
    
    fs = "\
    style[servers_filter;border=false;textcolor=#aaa]\
    image["..(size.x *0.095)..","..(size.y *0.1 -0.85)..";"..(size.x *0.81 -2.55)..",0.75;"..assets.."btn_bg_2_light.png;8,8]\
    field["..(size.x *0.095 +0.1)..","..(size.y *0.1 -0.85)..";"..(size.x *0.81 -2.2)..",0.75;servers_filter;;"..(state.menu_vars.servers_filter or "").."]\
    style[servers_search,servers_refresh,servers_cancel;bgimg="..assets.."btn_bg_2.png;bgimg_middle=8,8]\
    image_button["..(size.x *0.91 -0.85)..","..(size.y *0.1 -0.85)..";0.75,0.75;"..assets.."refresh.png;servers_refresh;]\
    image_button["..(size.x *0.91 -1.7)..","..(size.y *0.1 -0.85)..";0.75,0.75;"..assets.."cancel.png;servers_cancel;]\
    image_button["..(size.x *0.91 -2.55)..","..(size.y *0.1 -0.85)..";0.75,0.75;"..assets.."search.png;servers_search;]\
    image["..(size.x *0.095)..","..(size.y *0.1)..";"..(size.x *0.81)..","..(size.y *0.8)..";"..assets.."btn_bg.png;8,8]\
    scroll_container[0,"..(size.y *0.1 +0.1)..";"..size.x..","..(size.y *0.8 -0.2)..";serverscroll;vertical;;0,0]\
    "
    local listx = size.x *0.1
    local infox = state.current_server and size.x *0.6 or size.x *0.9
    local max = size.x *0.9
    local i = 0
--    if #state.favorite_servers > 0 then
--        fs = fs.."\
--        box["..listx..","..(i *0.5)..";"..(infox -listx)..",0.5;#"..(i %2 == 1 and "373530" or "403e39").."ff]\
--        box["..(listx -0.05)..","..(i *0.5 +0.2)..";"..(infox -listx +0.1)..",0.1;#292d2fff]\
--        box["..((infox -listx) /2 -1.5)..","..(i *0.5)..";3,0.5;#"..(i %2 == 1 and "373530" or "403e39").."ff]\
--        box["..((infox -listx) /2 -1.55)..","..(i *0.5 +0.125)..";0.1,0.25;#292d2fff]\
--        box["..((infox -listx) /2 +1.45)..","..(i *0.5 +0.125)..";0.1,0.25;#292d2fff]\
--        hypertext["..((infox -listx) /2 -1.5)..","..(i *0.5)..";3,0.5;;<global valign=middle halign=center color=#aaa>Favorite Servers]\
--        "
--        i = i +1
--    end
--    for idx, x in ipairs(state.favorite_servers) do
--        if x.address and x.port then
--            local address = minetest.encode_base64(x.address)
--            if address == state.current_server then
--                current_server = x
--            end
--            if address == state.joining_server then
--                joining_server = x
--            end
--            fs = fs.."\
--            style[serverinfof"..idx..";border=false;bgimg="..assets.."white.png;bgimg_middle=0;bgcolor=#"..(i %2 == 1 and "373530" or "403e39").."ff]\
--            style[serverinfof"..idx..":hovered;border=false;bgimg="..assets.."white.png;bgimg_middle=0]\
--            button["..listx..","..(i *0.5)..";"..(infox -listx)..",0.5;serverinfof"..idx..";]\
--            label["..(listx +0.1)..","..(i *0.5 +0.25)..";"..fe(x.address..":"..x.port).."]\
--            "
--            i = i +1
--        end
--    end
--    if i > 0 then
--        fs = fs.."\
--        box["..listx..","..(i *0.5)..";"..(infox -listx)..",0.5;#"..(i %2 == 1 and "373530" or "403e39").."ff]\
--        box["..(listx -0.05)..","..(i *0.5 +0.2)..";"..(infox -listx +0.1)..",0.1;#292d2fff]\
--        box["..((infox -listx) /2 -1.5)..","..(i *0.5)..";3,0.5;#"..(i %2 == 1 and "373530" or "403e39").."ff]\
--        box["..((infox -listx) /2 -1.55)..","..(i *0.5 +0.125)..";0.1,0.25;#292d2fff]\
--        box["..((infox -listx) /2 +1.45)..","..(i *0.5 +0.125)..";0.1,0.25;#292d2fff]\
--        hypertext["..((infox -listx) /2 -1.5)..","..(i *0.5)..";3,0.5;;<global valign=middle halign=center color=#aaa>Public Servers]\
--        "
--        i = i +1
--    end
    for idx, x in ipairs(state.serverlist) do
        -- Skip incompatible servers. You can't join them, so showing them is rather pointless.
        if (x.proto_max or version.proto_min) >= version.proto_min then
            local ping_lvl = 0
            local lag = (x.lag or 0) * 1000 + (x.ping or 0) * 250
            if lag <= 125 then
                ping_lvl = 4
            elseif lag <= 175 then
                ping_lvl = 3
            elseif lag <= 250 then
                ping_lvl = 2
            elseif lag <= 400 then
                ping_lvl = 1
            end
            
            local name = x.name and x.name:trim() or ""
            if name == "" then
                name = minetest.colorize("#888", x.address..":"..x.port)
            end
            -- Otherwise, the colons in an IPv6 address would make the style element blow up.
            --local address = minetest.encode_base64(x.address)
            local label_offset = 0.1
            fs = fs.."\
            style[serverinfo"..idx..";border=false;bgimg="..assets.."white.png;bgimg_middle=0;bgcolor=#"..(i %2 == 1 and "373530" or "403e39").."ff]\
            style[serverinfo"..idx..":hovered;border=false;bgimg="..assets.."white.png;bgimg_middle=0]\
            button["..listx..","..(i *0.5)..";"..(infox -listx)..",0.5;serverinfo"..idx..";]\
            "
            if x.favorite then
                -- The overlay dialog doesn't occlude area tooltips, so they are disabled in that case.
                fs = fs.."\
                image["..(listx)..","..(i *0.5)..";0.5,0.5;"..assets.."menu_servers_favorite.png]\
                "..(state.joining_server and "" or "tooltip["..(listx)..","..(i *0.5)..";0.5,0.5;Favorite server;#444;#aaa]\
                ")
                label_offset = 0.6
            end
            fs = fs.."\
            label["..(listx +label_offset)..","..(i *0.5 +0.25)..";"..fe(name).."]\
            "..((x.ping or x.lag) and "image["..(infox -0.6)..","..(i *0.5)..";0.5,0.5;"..assets.."menu_servers_icon_ping_"..ping_lvl..".png]\
            "..(state.joining_server and "" or "tooltip["..(infox -0.6)..","..(i *0.5)..";0.5,0.5;Ping: "..math.floor(lag)..";#444;#aaa]\
            ") or "")
            i = i +1
        end
    end
    if loading then
        fs = fs.."\
        hypertext["..listx..","..(i *0.5)..";"..(infox -listx)..",0.5;;<global valign=middle halign=center color=#777>Loading...]\
        "
    end
    fs = fs.."\
    scroll_container_end[]\
    scrollbar[-800,0;1,1;vertical;serverscroll;"..(state.menu_vars.serverscroll and tonumber(state.menu_vars.serverscroll:sub(5)) or 0).."]\
    "
    if state.current_server then
        fs = fs.."box["..(infox -0.05)..","..(size.y *0.1 +0.05)..";0.1,"..(size.y *0.8 -0.1)..";#292d2fff]\
        container["..infox..","..(size.y *0.1).."]\
        hypertext[0,0;"..(max -infox)..",0.75;;<global valign=middle halign=center color=#aaa><b>"..fe(hte(state.current_server.name or state.current_server.address..":"..state.current_server.port)).."</b>]\
        image[0.1,0.75;"..(max -infox -0.2)..",0.5;"..assets.."btn_bg_2_dark.png;8,8]\
        box["..((max -infox) *0.7 -0.05)..",0.75;0.1,0.5;#292d2fff]\
        hypertext[0.2,0.8;"..((max -infox) *0.7 -0.2)..",0.5;server_address;<global valign=middle color=#aaa>"..fe(hte(state.current_server.address)).."]\
        hypertext["..((max -infox) *0.7 +0.1)..",0.8;"..((max -infox) *0.3 -0.2)..",0.5;server_port;<global valign=middle color=#aaa>"..fe(hte(tostring(state.current_server.port))).."]\
        hypertext[0.1,1.5;"..(max -infox -0.2)..","..((size.y *0.8 -1.5 -1.05))..";server_desc;<global color=#aaa>"..fe(hte(state.current_server.description or "")).."]\
        button[0.1,"..(size.y *0.8 -1)..";"..(max -infox -0.2)..",0.75;join_server;Join Server]\
        container_end[]\
        "
    end
    
    fs = fs.."\
    button[0,"..(size.y -1)..";1,1;to_meta_menu;<]\
    "
    
    if state.joining_server or state.connecting_to_server then
        local offset = 0
        if state.server_connection_error then
            offset = offset +1
            fs= fs.."\
            hypertext[0,0;"..(size.x *0.5)..",1;;<global valign=middle color=#faa>"..fe(hte(state.server_connection_error)).."]\
            "
        end
        fs = fs.."\
        box[0,0;"..size.x..","..size.y..";#0008]\
        image["..(size.x *0.25 -0.2)..","..(size.y *0.25 -0.1)..";"..(size.x *0.5 +0.4)..","..(size.y *0.5 +0.2)..";"..assets.."btn_bg.png;8,8]\
        scroll_container["..(size.x *0.25)..","..(size.y *0.25)..";"..(size.x *0.5)..","..(size.y *0.5 +0.2)..";serverconfscroll;vertical;;0,0]\
        hypertext[0,"..offset..";"..(size.x *0.5)..",0.75;;<global valign=middle halign=center color=#aaa>Connecting to <b>"..fe(hte(state.current_server.name or state.current_server.address..":"..state.current_server.port)).."</b>...]\
        image[0,"..(1.25 +offset)..";"..(size.x *0.5)..",0.75;"..assets.."btn_bg_2_light.png;8,8]\
        label[0.2,"..(1.1 +offset)..";Username]\
        field[0.2,"..(1.25 +offset)..";"..(size.x *0.5 -0.4)..",0.75;server_username;;"..minetest.settings:get("name").."]\
        image[0,"..(2.25 +offset)..";"..(size.x *0.5)..",0.75;"..assets.."btn_bg_2_light.png;8,8]\
        style[server_password;border=false;textcolor=#aaa;bgimg="..assets.."btn_bg.png]\
        label[0.2,"..(2.1 +offset)..";Password]\
        pwdfield[0.2,"..(2.25 +offset)..";"..(size.x *0.5 -0.4)..",0.75;server_password;]\
        button[0,"..(3.25 +offset)..";"..(size.x *0.5)..",0.75;cancel_join_server;Cancel]\
        button[0,"..(4.25 +offset)..";"..(size.x *0.5)..",0.75;confirm_join_server;Join]\
        scroll_container_end[]\
        scrollbar[-800,0;1,1;vertical;serverconfscroll;"..(state.menu_vars.serverconfscroll and tonumber(state.menu_vars.serverconfscroll:sub(5)) or 0).."]\
        "
    end
    minetest.update_formspec(servers_header..fs)
end

-- Shows the content manager.
function show_content_menu()
    local fs = ""
    minetest.update_formspec(content_header..fs.."\
    button[0,"..(size.y -1)..";1,1;to_meta_menu;<]\
    ")
end

function minetest.button_handler(data)
    state.menu_vars = data
    if state.loc == "games" then
        if data.content or data.ht == "action:content" then
            if state.loc ~= "content" then show_content() end
        elseif data.games then
            if state.loc ~= "games" then show_meta_menu() end
        elseif data.carousel and data.carousel:sub(1, 4) == "CHG:" then
            local v = tonumber(data.carousel:sub(5))
            show_meta_menu(v)
        else
            for k, v in pairs(data) do
                if k:sub(1, 4) == "game" then
                    local id = k:sub(5)
                    state.current_game = get_game_info(id)
                    state.menu_current = {"main"}
                    state.loc = "game"
                    state.menu_vars = {}
                    show_game_menu()
                    minetest.settings:set("menu_last_game", id)
                    last_game = id
                elseif k:sub(1, 4) == "jump" then
                    local v = tonumber(k:sub(5))
                    show_meta_menu(v)
                end
            end
        end
    elseif state.loc == "servers" then
        if data.servers_refresh then
            refresh_server_list()
        elseif data.servers_search or data.key_enter_field == "servers_filter" then
            state.servers_filter = data.servers_filter
            show_servers_menu()
        elseif data.servers_cancel then
            state.servers_filter = nil
            show_servers_menu()
        elseif data.join_server then
            state.joining_server = true
            show_servers_menu()
        elseif data.cancel_join_server then
            state.joining_server = nil
            show_servers_menu()
        elseif data.confirm_join_server or data.key_enter_field == "server_username" or data.key_enter_field == "server_password" then
            minetest.settings:set("name", data.server_username)
            minetest.settings:set("address", state.current_server.address)
            minetest.settings:set("remote_port", state.current_server.port)
            gamedata = {
                playername = data.server_username,
                password = data.server_password,
                address = state.current_server.address,
                port = state.current_server.port,
                selected_world = 0,
                singleplayer = false
            }

            minetest.start()
        else
            for k, v in pairs(data) do
                if k:sub(1, string.len("serverinfo")) == "serverinfo" then
                    local idx = k:sub(string.len("serverinfo>"))
                    if idx:sub(1, 1) == "f" then
                        state.current_server = state.favorite_servers[tonumber(idx:sub(2))]
                    else
                        state.current_server = state.serverlist[tonumber(idx)]
                    end
                    show_servers_menu()
                end
            end
        end
    elseif state.loc == "content" then
        for k, v in pairs(data) do
            
        end
    elseif state.loc == "game" then
        for k, v in pairs(data) do
            if k:sub(1, string.len(".show_dialog_")) == ".show_dialog_" then
                show_game_menu {
                    show_dialog = k:sub(string.len(".show_dialog_>"))
                }
            elseif k:sub(1, string.len(".overlay_dialog_")) == ".overlay_dialog_" then
                show_game_menu {
                    overlay_dialog = k:sub(string.len(".overlay_dialog_>"))
                }
            elseif k == ".unoverlay_dialog" then
                show_game_menu {
                    unoverlay_dialog = true
                }
            end
        end
    end
    if data.to_meta_menu then
        state.current_game = nil
        state.loc = "games"
        show_meta_menu()
    elseif data.show_servers_view then
        state.current_game = nil
        state.loc = "servers"
        show_servers_menu()
    elseif data.show_content_view then
        state.current_game = nil
        state.loc = "content"
        show_content_menu()
    end
end

function minetest.event_handler(ev)
    -- Quit on quit
    if ev == "MenuQuit" then
        if state.joining_server then
            state.joining_server = nil
            show_servers_menu()
        elseif state.loc ~= "games" then
            show_meta_menu()
        else
            minetest.close()
        end
    end
end

minetest.set_clouds(false)

if last_game then
    state.current_game = get_game_info(last_game)
    state.menu_current = {"main"}
    state.loc = "game"
    show_game_menu()
else
    show_meta_menu()
end

--]]