-- osc.lua

local assdraw = require 'mp.assdraw'
local msg = require 'mp.msg'

--
-- Parameters
--

-- default user option values
-- do not touch, change them in plugin_osc.conf
local user_opts = {
    showwindowed = true,                    -- show OSC when windowed?
    showfullscreen = true,                  -- show OSC when fullscreen?
    scalewindowed = 1,                      -- scaling of the controller when windowed
    scalefullscreen = 1,                    -- scaling of the controller when fullscreen
    scaleforcedwindow = 2,                  -- scaling of the controller when rendered on a forced (dummy) window
    vidscale = true,                        -- scale the controller with the video?
    valign = 0.8,                           -- vertical alignment, -1 (top) to 1 (bottom)
    halign = 0,                             -- horizontal alignment, -1 (left) to 1 (right)
    boxalpha = 80,                          -- alpha of the background box, 0 (opaque) to 255 (fully transparent)
    hidetimeout = 500,                      -- duration in ms until the OSC hides if no mouse movement, negative value disables autohide
    fadeduration = 200,                     -- duration of fade out in ms, 0 = no fade
    deadzonesize = 0,                       -- size of deadzone
    minmousemove = 3,                       -- minimum amount of pixels the mouse has to move between ticks to make the OSC show up
    seektooltip = false,                    -- display tooltip over the seekbar indicating time at mouse position
    iamaprogrammer = false,                 -- use native mpv values and disable OSC internal playlist management (and some functions that depend on it)
}

local osc_param = {
    osc_w = 550,                            -- width, height, corner-radius, padding of the OSC box
    osc_h = 138,
    osc_r = 10,
    osc_p = 15,

    -- calculated by osc_init()
    playresy = 0,                           -- canvas size Y
    playresx = 0,                           -- canvas size X
    posX, posY = 0,0,                       -- position of the controler
    pos_offsetX, pos_offsetY = 0,0,         -- vertical/horizontal position offset for contents aligned at the borders of the box
}

local osc_styles = {
    bigButtons = "{\\blur0\\bord0\\1c&HFFFFFF\\3c&HFFFFFF\\fs50\\fnmpv-osd-symbols}",
    smallButtonsL = "{\\blur0\\bord0\\1c&HFFFFFF\\3c&HFFFFFF\\fs20\\fnmpv-osd-symbols}",
    smallButtonsLlabel = "{\\fs17\\fn" .. mp.get_property("options/osd-font") .. "}",
    smallButtonsR = "{\\blur0\\bord0\\1c&HFFFFFF\\3c&HFFFFFF\\fs30\\fnmpv-osd-symbols}",

    elementDown = "{\\1c&H999999}",
    timecodes = "{\\blur0\\bord0\\1c&HFFFFFF\\3c&HFFFFFF\\fs20}",
    vidtitle = "{\\blur0\\bord0\\1c&HFFFFFF\\3c&HFFFFFF\\fs12}",
    box = "{\\rDefault\\blur0\\bord1\\1c&H000000\\3c&HFFFFFF}",
}

-- internal states, do not touch
local state = {
    showtime,                               -- time of last invocation (last mouse move)
    osc_visible = false,
    anistart,                               -- time when the animation started
    anitype,                                -- current type of animation
    animation,                              -- current animation alpha
    mouse_down_counter = 0,                 -- used for softrepeat
    active_element = nil,                   -- nil = none, 0 = background, 1+ = see elements[]
    active_event_source = nil,              -- the "button" that issued the current event
    rightTC_trem = true,                    -- if the right timcode should display total or remaining time
    tc_ms = false,                          -- Should the timecodes display their time with milliseconds
    mp_screen_sizeX, mp_screen_sizeY,       -- last screen-resolution, to detect resolution changes to issue reINITs
    initREQ = false,                        -- is a re-init request pending?
    last_seek,                              -- last seek position, to avoid deadlocks by repeatedly seeking to the same position
    last_mouseX, last_mouseY,                -- last mouse position, to detect siginificant mouse movement
    message_text,
    message_timeout,
}

--
-- User Settings Management
--

function val2str(val)
    local strval = val
    if type(val) == "boolean" then
        if val then strval = "yes" else strval = "no" end
    end

    return strval
end

-- converts val to type of desttypeval
function typeconv(desttypeval, val)
    if type(desttypeval) == "boolean" then
        if val == "yes" then
            val = true
        elseif val == "no" then
            val = false
        else
            msg.error("Error: Can't convert " .. val .. " to boolean!")
            val = nil
        end
    elseif type(desttypeval) == "number" then
        if not (tonumber(val) == nil) then
            val = tonumber(val)
        else
            msg.error("Error: Can't convert " .. val .. " to number!")
            val = nil
        end
    end
    return val
end

-- Automagical config handling
-- options:     A table with options setable via config with assigned default values. The type of the default values is important for
--              converting the values read from the config file back. Do not use "nil" as a default value!
-- identifier:  A simple indentifier string for the config file. Make sure this doesn't collide with other scripts.

-- How does it work:
-- Existance of the configfile will be checked, if it doesn't exist, the default values from the options table will be written in a new
-- file, commented out. If it exits, the key/value pairs will be read, and values of keys that exist in the options table will overwrite
-- their value. Keys that don't exist in the options table will be ignored, keys that don't exits in the config will keep their default
-- value. The value's types will automatically be converted to the type used in the options table.
function read_config(options, identifier)

    local conffilename = "plugin_" .. identifier .. ".conf"
    local conffile = mp.find_config_file(conffilename)
    local f = conffile and io.open(conffile,"r")
    if f == nil then
        -- config not found
    else
        -- config exists, read values
        local linecounter = 1
        for line in f:lines() do
            if string.find(line, "#") == 1 then

            else
                local eqpos = string.find(line, "=")
                if eqpos == nil then

                else
                    local key = string.sub(line, 1, eqpos-1)
                    local val = string.sub(line, eqpos+1)

                    -- match found values with defaults
                    if options[key] == nil then
                        msg.warn(conffilename..":"..linecounter.." unknown key " .. key .. ", ignoring")
                    else
                        local convval = typeconv(options[key], val)
                        if convval == nil then
                            msg.error(conffilename..":"..linecounter.." error converting value '" .. val .. "' for key '" .. key .. "'")
                        else
                            options[key] = convval
                        end
                    end
                end
            end
            linecounter = linecounter + 1
        end
        io.close(f)
    end
end

-- read configfile
read_config(user_opts, "osc")


--
-- Helperfunctions
--

function scale_value(x0, x1, y0, y1, val)
    local m = (y1 - y0) / (x1 - x0)
    local b = y0 - (m * x0)
    return (m * val) + b
end

-- returns hitbox spanning coordinates (top left, bottom right corner) according to alignment
function get_hitbox_coords(x, y, an, w, h)

    local alignments = {
      [1] = function () return x, y-h, x+w, y end,
      [2] = function () return x-(w/2), y-h, x+(w/2), y end,
      [3] = function () return x-w, y-h, x, y end,

      [4] = function () return x, y-(h/2), x+w, y+(h/2) end,
      [5] = function () return x-(w/2), y-(h/2), x+(w/2), y+(h/2) end,
      [6] = function () return x-w, y-(h/2), x, y+(h/2) end,

      [7] = function () return x, y, x+w, y+h end,
      [8] = function () return x-(w/2), y, x+(w/2), y+h end,
      [9] = function () return x-w, y, x, y+h end,
    }

    return alignments[an]()
end

function get_element_hitbox(element)
    return element.hitbox.x1, element.hitbox.y1, element.hitbox.x2, element.hitbox.y2
end

function mouse_hit(element)
    local mX, mY = mp.get_mouse_pos()
    local bX1, bY1, bX2, bY2 = get_element_hitbox(element)

    return (mX >= bX1 and mX <= bX2 and mY >= bY1 and mY <= bY2)
end

function limit_range(min, max, val)
    if val > max then
        val = max
    elseif val < min then
        val = min
    end
    return val
end

function get_slider_value(element)
    local fill_offsetV = element.metainfo.slider.border + element.metainfo.slider.gap
    local paddingH = (element.h - (2*fill_offsetV)) / 2

    local b_x1, b_x2 = element.hitbox.x1 + paddingH, element.hitbox.x2 - paddingH
    local s_min, s_max = element.metainfo.slider.min, element.metainfo.slider.max

    local pos = scale_value(b_x1, b_x2, s_min, s_max, mp.get_mouse_pos())

    return limit_range(s_min, s_max, pos)
end

function countone(val)
    if not (user_opts.iamaprogrammer) then
        val = val + 1
    end
    return val
end

-- align:  -1 .. +1
-- frame:  size of the containing area
-- obj:    size of the object that should be positioned inside the area
-- margin: min. distance from object to frame (as long as -1 <= align <= +1)
function get_align(align, frame, obj, margin)
    return (frame / 2) + (((frame / 2) - margin - (obj / 2)) * align)
end

-- multiplies two alpha values, formular can probably be improved
function mult_alpha(alphaA, alphaB)
    return 255 - (((1-(alphaA/255)) * (1-(alphaB/255))) * 255)
end

--
-- Tracklist Management
--

local nicetypes = {video = "Video", audio = "Audio", sub = "Subtitle"}

-- updates the OSC internal playlists, should be run each time the track-layout changes
function update_tracklist()
    local tracktable = mp.get_property_native("track-list", {})

    -- by osc_id
    tracks_osc = {}
    tracks_osc.video, tracks_osc.audio, tracks_osc.sub = {}, {}, {}
    -- by mpv_id
    tracks_mpv = {}
    tracks_mpv.video, tracks_mpv.audio, tracks_mpv.sub = {}, {}, {}
    for n = 1, #tracktable do
        if not (tracktable[n].type == "unkown") then
            local type = tracktable[n].type
            local mpv_id = tonumber(tracktable[n].id)

            -- by osc_id
            table.insert(tracks_osc[type], tracktable[n])

            -- by mpv_id
            tracks_mpv[type][mpv_id] = tracktable[n]
            tracks_mpv[type][mpv_id].osc_id = #tracks_osc[type]
        end
    end
end

-- return a nice list of tracks of the given type (video, audio, sub)
function get_tracklist(type)
    local msg = "Available " .. nicetypes[type] .. " Tracks: "
    local select_scale = 100
    if #tracks_osc[type] == 0 then
        msg = msg .. "none"
    else
        for n = 1, #tracks_osc[type] do
            local track = tracks_osc[type][n]
            local lang, title, selected = "unkown", "", "{\\fscx" .. select_scale .. "\\fscy" .. select_scale .. "}○{\\fscx100\\fscy100}"
            if not(track.lang == nil) then lang = track.lang end
            if not(track.title == nil) then title = track.title end
            if (track.id == tonumber(mp.get_property(type))) then
                selected = "{\\fscx" .. select_scale .. "\\fscy" .. select_scale .. "}●{\\fscx100\\fscy100}"
            end
            msg = msg .. "\n" .. selected .. " " .. n .. ": [" .. lang .. "] " .. title
        end
    end
    return msg
end

-- relatively change the track of given <type> by <next> tracks (+1 -> next, -1 -> previous)
function set_track(type, next)
    local current_track_mpv, current_track_osc
    if (mp.get_property(type) == "no") then
        current_track_osc = 0
    else
        current_track_mpv = tonumber(mp.get_property(type))
        current_track_osc = tracks_mpv[type][current_track_mpv].osc_id
    end
    local new_track_osc = (current_track_osc + next) % (#tracks_osc[type] + 1)
    local new_track_mpv
    if new_track_osc == 0 then
        new_track_mpv = "no"
    else
        new_track_mpv = tracks_osc[type][new_track_osc].id
    end

    mp.commandv("set", type, new_track_mpv)

        if (new_track_osc == 0) then
        show_message(nicetypes[type] .. " Track: none")
    else
        show_message(nicetypes[type]  .. " Track: " .. new_track_osc .. "/" .. #tracks_osc[type]
            .. " [" .. (tracks_osc[type][new_track_osc].lang or "unkown") .. "] " .. (tracks_osc[type][new_track_osc].title or ""))
    end
end

-- get the currently selected track of <type>, OSC-style counted
function get_track(type)
    local track = mp.get_property(type)
    if (track == "no" or track == nil) then
        return 0
    else
        return tracks_mpv[type][tonumber(track)].osc_id
    end
end


--
-- Element Management
--

-- do not use this function, use the wrappers below
function register_element(type, x, y, an, w, h, style, content, eventresponder, metainfo2)
    -- type             button, slider or box
    -- x, y             position
    -- an               alignment (see ASS standard)
    -- w, h             size of hitbox
    -- style            main style
    -- content          what the element should display, can be a string or a function(ass)
    -- eventresponder   A table containing functions mapped to events that shall be run on those events
    -- metainfo         A table containing additional parameters for the element

    -- set default metainfo
    local metainfo = {}
    if not (metainfo2 == nil) then metainfo = metainfo2 end
    if metainfo.visible == nil then metainfo.visible = true end         -- element visible at all?
    if metainfo.enabled == nil then metainfo.enabled = true end         -- element clickable?
    if metainfo.styledown == nil then metainfo.styledown = true end     -- should the element be styled with the elementDown style when clicked?
    if metainfo.softrepeat == nil then metainfo.softrepeat = false end  -- should the *_down event be executed with "hold for repeat" behaviour?
    if metainfo.alpha1 == nil then metainfo.alpha1 = 0 end              -- alpha1 of the element, 0 = opaque, 255 = transparent (primary fill alpha)
    if metainfo.alpha2 == nil then metainfo.alpha2 = 255 end            -- alpha1 of the element, 0 = opaque, 255 = transparent (secondary fill alpha)
    if metainfo.alpha3 == nil then metainfo.alpha3 = 255 end            -- alpha1 of the element, 0 = opaque, 255 = transparent (border alpha)
    if metainfo.alpha4 == nil then metainfo.alpha4 = 255 end            -- alpha1 of the element, 0 = opaque, 255 = transparent (shadow alpha)

    if metainfo.visible then
        local ass = assdraw.ass_new()

        ass:append("{}") -- shitty hack to troll the new_event function into inserting a \n
        ass:new_event()
        ass:pos(x, y) -- positioning
        ass:an(an)
        ass:append(style) -- styling

        -- if the element is supposed to be disabled, style it accordingly and kill the eventresponders
        if metainfo.enabled == false then
            metainfo.alpha1 = 136
            eventresponder = nil
        end

        -- Calculate the hitbox
        local bX1, bY1, bX2, bY2 = get_hitbox_coords(x, y, an, w, h)
        local hitbox
        if type == "slider" then
            -- if it's a slider, cut the border and gap off, as those aren't of interest for eventhandling
            local fill_offset = metainfo.slider.border + metainfo.slider.gap
            hitbox = {x1 = bX1 + fill_offset, y1 = bY1 + fill_offset, x2 = bX2 - fill_offset, y2 = bY2 - fill_offset}
        else
            hitbox = {x1 = bX1, y1 = bY1, x2 = bX2, y2 = bY2}
        end

        local element = {
            type = type,
            elem_ass = ass,
            hitbox = hitbox,
            w = w,
            h = h,
            x = x,
            y = y,
            content = content,
            eventresponder = eventresponder,
            metainfo = metainfo,
        }

        table.insert(elements, element)
    end
end

function register_button(x, y, an, w, h, style, content, eventresponder, metainfo)
    register_element("button", x, y, an, w, h, style, content, eventresponder, metainfo)
end

function register_box(x, y, an, w, h, r, style, metainfo2)
    local ass = assdraw.ass_new()
    ass:draw_start()
    ass:round_rect_cw(0, 0, w, h, r)
    ass:draw_stop()

    local metainfo = {}
        if not (metainfo2 == nil) then metainfo = metainfo2 end

    metainfo.styledown = false

    register_element("box", x, y, an, w, h, style, ass, nil, metainfo)
end

function register_slider(x, y, an, w, h, style, min, max, markerF, posF, eventresponder, metainfo2)
    local metainfo = {}
    if not (metainfo2 == nil) then metainfo = metainfo2 end
    local slider1 = {}
    if (metainfo.slider == nil) then metainfo.slider = slider1 end

    -- defaults
    if min == nil then metainfo.slider.min = 0 else metainfo.slider.min = min end
    if max == nil then metainfo.slider.max = 100 else metainfo.slider.max = max end
    if metainfo.slider.border == nil then metainfo.slider.border = 1 end
    if metainfo.slider.gap == nil then metainfo.slider.gap = 2 end
    if metainfo.slider.type == nil then metainfo.slider.type = "slider" end

    metainfo.slider.markerF = markerF
    metainfo.slider.posF = posF

    -- prepare the box with markers
    local ass = assdraw.ass_new()
    local border, gap = metainfo.slider.border, metainfo.slider.gap
    local fill_offsetV = border + gap       -- Vertical offset between element outline and drag-area
    local fill_offsetH = h / 2              -- Horizontal offset between element outline and drag-area

    ass:draw_start()

    -- the box
    ass:rect_cw(0, 0, w, h);

    -- the "hole"
    ass:rect_ccw(border, border, w - border, h - border)

    -- marker nibbles
    if not (markerF == nil) and gap > 0 then
        local markers = markerF()
        for n = 1, #markers do
            if (markers[n] > min) and (markers[n] < max) then

                local coordL, coordR = fill_offsetH, (w - fill_offsetH)

                local s = scale_value(min, max, coordL, coordR, markers[n])

                if gap > 1 then
                    -- draw triangles
                    local a = gap / 0.5 --0.866
                    --top
                    ass:move_to(s - (a/2), border)
                    ass:line_to(s + (a/2), border)
                    ass:line_to(s, border + gap)

                    --bottom
                    ass:move_to(s - (a/2), h - border)
                    ass:line_to(s, h - border - gap)
                    ass:line_to(s + (a/2), h - border)

                else
                    -- draw 1px nibbles
                    ass:rect_cw(s - 0.5, border, s + 0.5, border*2);
                    ass:rect_cw(s - 0.5, h - border*2, s + 0.5, h - border);
                end

            end
        end
    end

    register_element("slider", x, y, an, w, h, style, ass, eventresponder, metainfo)
end

--
-- Element Rendering
--

function render_elements(master_ass)

    for n = 1, #elements do

        local element = elements[n]
        local elem_ass = assdraw.ass_new()
        local elem_ass1 = element.elem_ass
        elem_ass:merge(elem_ass1)

        --alpha
        local alpha1 = element.metainfo.alpha1
        local alpha2 = element.metainfo.alpha2
        local alpha3 = element.metainfo.alpha3
        local alpha4 = element.metainfo.alpha4

        if not(state.animation == nil) then
            alpha1 = mult_alpha(element.metainfo.alpha1, state.animation)
            alpha2 = mult_alpha(element.metainfo.alpha2, state.animation)
            alpha3 = mult_alpha(element.metainfo.alpha3, state.animation)
            alpha4 = mult_alpha(element.metainfo.alpha4, state.animation)
        end

        elem_ass:append(string.format("{\\1a&H%X&\\2a&H%X&\\3a&H%X&\\4a&H%X&}", alpha1, alpha2, alpha3, alpha4))


        if state.active_element == n then

            -- run render event functions
            if not (element.eventresponder.render == nil) then
                element.eventresponder.render(element)
            end

            if mouse_hit(element) then
                -- mouse down styling
                if element.metainfo.styledown then
                    elem_ass:append(osc_styles.elementDown)
                end

                if (element.metainfo.softrepeat == true) and (state.mouse_down_counter >= 15 and state.mouse_down_counter % 5 == 0) then
                    element.eventresponder[state.active_event_source .. "_down"](element)
                end
                state.mouse_down_counter = state.mouse_down_counter + 1
            end

        end

        if element.type == "slider" then

            elem_ass:merge(element.content) -- ASS objects

            -- draw pos marker
            local pos = element.metainfo.slider.posF()

            if not (pos == nil) then

                pos = limit_range(element.metainfo.slider.min, element.metainfo.slider.max, pos)

                local fill_offsetV = element.metainfo.slider.border + element.metainfo.slider.gap
                local fill_offsetH = element.h/2

                local coordL, coordR = fill_offsetH, (element.w - fill_offsetH)

                local xp = scale_value(element.metainfo.slider.min, element.metainfo.slider.max, coordL, coordR, pos)

                -- the filling, draw it only if positive
                local innerH = element.h - (2*fill_offsetV)

                if element.metainfo.slider.type == "bar" then
                    elem_ass:rect_cw(fill_offsetV, fill_offsetV, xp, element.h - fill_offsetV)
                else
                    elem_ass:move_to(xp, fill_offsetV)
                    elem_ass:line_to(xp+(innerH/2), (innerH/2)+fill_offsetV)
                    elem_ass:line_to(xp, (innerH)+fill_offsetV)
                    elem_ass:line_to(xp-(innerH/2), (innerH/2)+fill_offsetV)
                end
            end

            elem_ass:draw_stop()

            -- add tooltip
            if not (element.metainfo.slider.tooltipF == nil) then

                if mouse_hit(element) then
                    local sliderpos = get_slider_value(element)
                    local tooltiplabel = element.metainfo.slider.tooltipF(sliderpos)
                    local s_min, s_max = element.metainfo.slider.min, element.metainfo.slider.max

                    local an = 2
                    if (sliderpos < (s_min + 10)) then
                        an = 1
                    elseif (sliderpos > (s_max - 10)) then
                        an = 3
                    end

                    elem_ass:new_event()
                    elem_ass:pos(mp.get_mouse_pos(), element.y - (element.h) - 0) -- positioning
                    elem_ass:an(an)
                    elem_ass:append(osc_styles.vidtitle) -- styling
                    elem_ass:append(tooltiplabel)

                end
            end



        elseif element.type == "box" then
            elem_ass:merge(element.content) -- ASS objects
        elseif type(element.content) == "function" then
            element.content(elem_ass) -- function objects
        else
            elem_ass:append(element.content) -- text objects
        end

        master_ass:merge(elem_ass)
    end
end

--
-- Message display
--

function show_message(text, duration)

    if duration == nil then
        duration = tonumber(mp.get_property("options/osd-duration")) / 1000
    end

    -- cut the text short, otherwise the following functions may slow down massively on huge input
    text = string.sub(text, 0, 4000)

    -- replace actual linebreaks with ASS linebreaks and get the amount of lines along the way
    local lines
    text, lines = string.gsub(text, "\n", "\\N")

    -- append a Zero-Width-Space to . and _ to enable linebreaking of long filenames
    text = string.gsub(text, "%.", ".\226\128\139")
    text = string.gsub(text, "_", "_\226\128\139")

    -- scale the fontsize for longer multi-line output
    local fontsize, outline = tonumber(mp.get_property("options/osd-font-size")), tonumber(mp.get_property("options/osd-border-size"))
    if lines > 12 then
        fontsize, outline = fontsize / 2, outline / 1.5
    elseif lines > 8 then
        fontsize, outline = fontsize / 1.5, outline / 1.25
    end

    local style = "{\\bord" .. outline .. "\\fs" .. fontsize .. "}"

    state.message_text = style .. text
    state.message_timeout = mp.get_time() + duration
end

function render_message(ass)
    if not(state.message_timeout == nil) and not(state.message_text == nil) and state.message_timeout > mp.get_time() then
        ass:new_event()
        ass:append(state.message_text)
    else
        state.message_text = nil
        state.message_timeout = nil
    end
end

--
-- Initialisation and Layout
--

-- OSC INIT
function osc_init()
    -- kill old Elements
    elements = {}

    -- set canvas resolution according to display aspect and scaling setting
    local baseResY = 720
    local display_w, display_h, display_aspect = mp.get_screen_size()
    local scale = 1

    if (mp.get_property("video") == "no") then -- dummy/forced window
        scale = user_opts.scaleforcedwindow
    elseif (mp.get_property("fullscreen") == "yes") then
        scale = user_opts.scalefullscreen
    else
        scale = user_opts.scalewindowed
    end


    if user_opts.vidscale then
        osc_param.playresy = baseResY / scale
    else
        osc_param.playresy = display_h / scale
    end
    osc_param.playresx = osc_param.playresy * display_aspect

    -- make sure the OSC actually fits into the video
    if (osc_param.playresx < (osc_param.osc_w + (2 * osc_param.osc_p))) then
        osc_param.playresy = (osc_param.osc_w + (2 * osc_param.osc_p)) / display_aspect
        osc_param.playresx = osc_param.playresy * display_aspect
    end

    -- position of the controller according to video aspect and valignment
    osc_param.posX = math.floor(get_align(user_opts.halign, osc_param.playresx, osc_param.osc_w, 0))
    osc_param.posY = math.floor(get_align(user_opts.valign, osc_param.playresy, osc_param.osc_h, 0))

    -- Some calculations on stuff we'll need
    -- vertical/horizontal position offset for contents aligned at the borders of the box
    osc_param.pos_offsetX, osc_param.pos_offsetY = (osc_param.osc_w - (2*osc_param.osc_p)) / 2, (osc_param.osc_h - (2*osc_param.osc_p)) / 2

    -- fetch values
    local osc_w, osc_h, osc_r, osc_p = osc_param.osc_w, osc_param.osc_h, osc_param.osc_r, osc_param.osc_p
    local pos_offsetX, pos_offsetY = osc_param.pos_offsetX, osc_param.pos_offsetY
    local posX, posY = osc_param.posX, osc_param.posY

    --
    -- Backround box
    --

    local metainfo = {}
    metainfo.alpha1 = user_opts.boxalpha
    metainfo.alpha3 = user_opts.boxalpha
    register_box(posX, posY, 5, osc_w, osc_h, osc_r, osc_styles.box, metainfo)

    --
    -- Title row
    --

    local titlerowY = posY - pos_offsetY - 10

    -- title
    local contentF = function (ass)
        local title = mp.get_property_osd("media-title")
        if not (title == nil) then

            if #title > 80 then
                title = string.format("{\\fscx%f}", (80 / #title) * 100) .. title
            end

            ass:append(title)
        else
            ass:append("mpv")
        end
    end

    local eventresponder = {}
    eventresponder.mouse_btn0_up = function ()

        local title = mp.get_property("media-title")
        local pl_count = tonumber(mp.get_property("playlist-count"))

        if pl_count > 1 then
            local playlist_pos = countone(tonumber(mp.get_property("playlist-pos")))
            title = "[" .. playlist_pos .. "/" .. pl_count .. "] " .. title
        end

        show_message(title)
    end
    eventresponder.mouse_btn2_up = function () show_message(mp.get_property("filename")) end

    register_button(posX, titlerowY, 8, 496, 12, osc_styles.vidtitle, contentF, eventresponder, nil)

    -- If we have more than one playlist entry, render playlist navigation buttons
    local metainfo = {}
    metainfo.visible = (tonumber(mp.get_property("playlist-count")) > 1)

    -- playlist prev
    local eventresponder = {}
    eventresponder.mouse_btn0_up = function () mp.commandv("playlist_prev", "weak") end
    eventresponder["shift+mouse_btn0_up"] = function () show_message(mp.get_property_osd("playlist"), 3) end
    register_button(posX - pos_offsetX, titlerowY, 7, 12, 12, osc_styles.vidtitle, "◀", eventresponder, metainfo)

    -- playlist next
    local eventresponder = {}
    eventresponder.mouse_btn0_up = function () mp.commandv("playlist_next", "weak") end
    eventresponder["shift+mouse_btn0_up"] = function () show_message(mp.get_property_osd("playlist"), 3) end
    register_button(posX + pos_offsetX, titlerowY, 9, 12, 12, osc_styles.vidtitle, "▶", eventresponder, metainfo)

    --
    -- Big buttons
    --

    local bigbuttonrowY = posY - pos_offsetY + 35
    local bigbuttondistance = 60

    --play/pause
    local contentF = function (ass)
        if mp.get_property("pause") == "yes" then
            ass:append("\238\132\129")
        else
            ass:append("\238\128\130")
        end
    end
    local eventresponder = {}
    eventresponder.mouse_btn0_up = function () mp.commandv("cycle", "pause") end
    register_button(posX, bigbuttonrowY, 5, 40, 40, osc_styles.bigButtons, contentF, eventresponder, nil)

    --skipback
    local metainfo = {}
    metainfo.softrepeat = true

    local eventresponder = {}
    eventresponder.mouse_btn0_down = function () mp.commandv("seek", -5, "relative", "keyframes") end
    eventresponder["shift+mouse_btn0_down"] = function () mp.commandv("frame_back_step") end
    eventresponder.mouse_btn2_down = function () mp.commandv("seek", -30, "relative", "keyframes") end
    register_button(posX - bigbuttondistance, bigbuttonrowY, 5, 40, 40, osc_styles.bigButtons, "\238\128\132", eventresponder, metainfo)

    --skipfrwd
    local eventresponder = {}
    eventresponder.mouse_btn0_down = function () mp.commandv("seek", 10, "relative", "keyframes") end
    eventresponder["shift+mouse_btn0_down"] = function () mp.commandv("frame_step") end
    eventresponder.mouse_btn2_down = function () mp.commandv("seek", 60, "relative", "keyframes") end
    register_button(posX + bigbuttondistance, bigbuttonrowY, 5, 40, 40, osc_styles.bigButtons, "\238\128\133", eventresponder, metainfo)

    --chapters
    -- do we have any?
    local metainfo = {}
    metainfo.enabled = ((#mp.get_property_native("chapter-list", {})) > 0)

    --prev
    local eventresponder = {}
    eventresponder.mouse_btn0_up = function () mp.commandv("osd-msg", "add", "chapter", -1) end
    eventresponder["shift+mouse_btn0_up"] = function () show_message(mp.get_property("chapter-list"), 3) end
    register_button(posX - (bigbuttondistance * 2), bigbuttonrowY, 5, 40, 40, osc_styles.bigButtons, "\238\132\132", eventresponder, metainfo)

    --next
    local eventresponder = {}
    eventresponder.mouse_btn0_up = function () mp.commandv("osd-msg", "add", "chapter", 1) end
    eventresponder["shift+mouse_btn0_up"] = function () show_message(mp.get_property("chapter-list"), 3) end
    register_button(posX + (bigbuttondistance * 2), bigbuttonrowY, 5, 40, 40, osc_styles.bigButtons, "\238\132\133", eventresponder, metainfo)


    --
    -- Smaller buttons
    --

    if not (user_opts.iamaprogrammer) then
        update_tracklist()
    end

    --cycle audio tracks

    local metainfo = {}
    local eventresponder = {}
    local contentF

    if not (user_opts.iamaprogrammer) then
        metainfo.enabled = (#tracks_osc.audio > 0)

        contentF = function (ass)
            local aid = "–"
            if not (get_track("audio") == 0) then
                aid = get_track("audio")
            end
            ass:append("\238\132\134" .. osc_styles.smallButtonsLlabel .. " " .. aid .. "/" .. #tracks_osc.audio)
        end

        eventresponder.mouse_btn0_up = function () set_track("audio", 1) end
        eventresponder.mouse_btn2_up = function () set_track("audio", -1) end
        eventresponder["shift+mouse_btn0_down"] = function ()
            show_message(get_tracklist("audio"), 2)
        end
    else
        metainfo.enabled = true
        contentF = function (ass)
            local aid = mp.get_property("audio")

            ass:append("\238\132\134" .. osc_styles.smallButtonsLlabel .. " " .. aid)
        end

        eventresponder.mouse_btn0_up = function () mp.commandv("osd-msg", "add", "audio", 1) end
        eventresponder.mouse_btn2_up = function () mp.commandv("osd-msg", "add", "audio", -1)  end
    end

    register_button(posX - pos_offsetX, bigbuttonrowY, 1, 70, 18, osc_styles.smallButtonsL, contentF, eventresponder, metainfo)


    --cycle sub tracks

    local metainfo = {}
    local eventresponder = {}
    local contentF

    if not (user_opts.iamaprogrammer) then
        metainfo.enabled = (#tracks_osc.sub > 0)

        contentF = function (ass)
            local sid = "–"
            if not (get_track("sub") == 0) then
                sid = get_track("sub")
            end
            ass:append("\238\132\135" .. osc_styles.smallButtonsLlabel .. " " .. sid .. "/" .. #tracks_osc.sub)
        end

        eventresponder.mouse_btn0_up = function () set_track("sub", 1) end
        eventresponder.mouse_btn2_up = function () set_track("sub", -1) end
        eventresponder["shift+mouse_btn0_down"] = function ()
            show_message(get_tracklist("sub"), 2)
        end
    else
        metainfo.enabled = true
        contentF = function (ass)
            local sid = mp.get_property("sub")

            ass:append("\238\132\135" .. osc_styles.smallButtonsLlabel .. " " .. sid)
        end

        eventresponder.mouse_btn0_up = function () mp.commandv("osd-msg", "add", "sub", 1) end
        eventresponder.mouse_btn2_up = function () mp.commandv("osd-msg", "add", "sub", -1)  end
    end
    register_button(posX - pos_offsetX, bigbuttonrowY, 7, 70, 18, osc_styles.smallButtonsL, contentF, eventresponder, metainfo)


    --toggle FS
    local contentF = function (ass)
        if mp.get_property("fullscreen") == "yes" then
            ass:append("\238\132\137")
        else
            ass:append("\238\132\136")
        end
    end
    local eventresponder = {}
    eventresponder.mouse_btn0_up = function () mp.commandv("cycle", "fullscreen") end
    register_button(posX+pos_offsetX, bigbuttonrowY, 6, 25, 25, osc_styles.smallButtonsR, contentF, eventresponder, nil)


    --
    -- Seekbar
    --

    local markerF = function ()
        local duration = 0
        if not (mp.get_property("length") == nil) then
            duration = tonumber(mp.get_property("length"))
        end

        local chapters = mp.get_property_native("chapter-list", {})
        local markers = {}
        for n = 1, #chapters do
            markers[n] = (chapters[n].time / duration * 100)
        end
        return markers
    end

    local posF = function ()
        if mp.get_property("percent-pos") == nil then
            return nil
        else
            return tonumber(mp.get_property("percent-pos"))
        end
    end

    local tooltipF = function (pos)
        if not (mp.get_property("length") == nil) then
            duration = tonumber(mp.get_property("length"))
            possec = duration * (pos / 100)
            return mp.format_time(possec)
        else
            return nil
        end
    end

    local metainfo = {}


    metainfo.enabled = not (mp.get_property("percent-pos") == nil)
    metainfo.styledown = false
    metainfo.slider = {}
    metainfo.slider.border = 1
    metainfo.slider.gap = 1             -- >1 will draw triangle markers
    metainfo.slider.type = "slider"     -- "bar" for old bar-style filling
    if (user_opts.seektooltip) and (not (mp.get_property("length") == nil)) then
        metainfo.slider.tooltipF = tooltipF
    end

    local eventresponder = {}
    local sliderF = function (element)
        local seek_to = get_slider_value(element)
        -- ignore identical seeks
        if not(state.last_seek == seek_to) then
            mp.commandv("seek", seek_to, "absolute-percent", "keyframes")
            state.last_seek = seek_to
        end
    end
    eventresponder.render = sliderF
    eventresponder.mouse_btn0_down = sliderF
    register_slider(posX, posY+pos_offsetY-22, 2, pos_offsetX*2, 15, osc_styles.timecodes, 0, 100, markerF, posF, eventresponder, metainfo)

    --
    -- Timecodes + Volume
    --

    local bottomrowY = posY + pos_offsetY - 5

    -- left (current pos)
    local metainfo = {}
    local eventresponder = {}

    local contentF = function (ass)
        if state.tc_ms then
            ass:append(mp.get_property_osd("time-pos/full"))
        else
            ass:append(mp.get_property_osd("time-pos"))
        end
    end

    eventresponder.mouse_btn0_up = function () state.tc_ms = not state.tc_ms end
    register_button(posX - pos_offsetX, bottomrowY, 4, 110, 18, osc_styles.timecodes, contentF, eventresponder, metainfo)

    -- center (Cache)
    local metainfo = {}
    local eventresponder = {}

    local contentF = function (ass)
        local cache = mp.get_property("cache")
        if not (cache == nil) then
            cache = tonumber(mp.get_property("cache"))
            if (cache < 45) then
                ass:append("Cache: " .. (cache) .."%")
            end
        end
    end
    register_button(posX, bottomrowY, 5, 110, 18, osc_styles.timecodes, contentF, eventresponder, metainfo)


    -- right (total/remaining time)
    -- do we have a usuable duration?
    local metainfo = {}
    metainfo.visible = (not (mp.get_property("length") == nil)) and (tonumber(mp.get_property("length")) > 0)

    local contentF = function (ass)
        if state.rightTC_trem == true then
            if state.tc_ms then
                ass:append("-" .. mp.get_property_osd("playtime-remaining/full"))
            else
                ass:append("-" .. mp.get_property_osd("playtime-remaining"))
            end
        else
            if state.tc_ms then
                ass:append(mp.get_property_osd("length/full"))
            else
                ass:append(mp.get_property_osd("length"))
            end
        end
    end
    local eventresponder = {}
    eventresponder.mouse_btn0_up = function () state.rightTC_trem = not state.rightTC_trem end

    register_button(posX + pos_offsetX, bottomrowY, 6, 110, 18, osc_styles.timecodes, contentF, eventresponder, metainfo)

end

--
-- Other important stuff
--


function show_osc()

    --remember last time of invocation (mouse move)
    state.showtime = mp.get_time()

    state.osc_visible = true

    if (user_opts.fadeduration > 0) then
        state.anitype = nil
    end

end

function hide_osc()
    if (user_opts.fadeduration > 0) then
        if not(state.osc_visible == false) then
            state.anitype = "out"
        end
    else
        state.osc_visible = false
    end
end

function mouse_leave()
    hide_osc()
    -- reset mouse position
    state.last_mouseX, state.last_mouseY = nil, nil
end

function request_init()
    state.initREQ = true
end

function render()
    local current_screen_sizeX, current_screen_sizeY = mp.get_screen_size()
    local mouseX, mouseY = mp.get_mouse_pos()
    local now = mp.get_time()

    -- check if display changed, if so request reinit
    if not (state.mp_screen_sizeX == current_screen_sizeX and state.mp_screen_sizeY == current_screen_sizeY) then
        request_init()
        state.mp_screen_sizeX, state.mp_screen_sizeY = current_screen_sizeX, current_screen_sizeY
    end

    -- init management
    if state.initREQ then
        osc_init()
        state.initREQ = false

        -- store initial mouse position
        if (state.last_mouseX == nil or state.last_mouseY == nil) and not (mouseX == nil or mouseY == nil) then
            state.last_mouseX, state.last_mouseY = mouseX, mouseY
        end
    end

    -- autohide
    if not (state.showtime == nil) and (user_opts.hidetimeout >= 0) and (state.showtime + (user_opts.hidetimeout/1000) < now) and (state.active_element == nil)
        and not (mouseX >= osc_param.posX - (osc_param.osc_w / 2) and mouseX <= osc_param.posX + (osc_param.osc_w / 2)
            and mouseY >= osc_param.posY - (osc_param.osc_h / 2) and mouseY <= osc_param.posY + (osc_param.osc_h / 2)) then
        hide_osc()
    end

    -- fade animation
    if not(state.anitype == nil) then

        if (state.anistart == nil) then
            state.anistart = now
        end

        if (now < state.anistart + (user_opts.fadeduration/1000)) then

            if (state.anitype == "in") then --fade in
                state.osc_visible = true
                state.animation = scale_value(state.anistart, (state.anistart + (user_opts.fadeduration/1000)), 255, 0, now)
            elseif (state.anitype == "out") then --fade in
                state.animation = scale_value(state.anistart, (state.anistart + (user_opts.fadeduration/1000)), 0, 255, now)
            end

        else
            if (state.anitype == "out") then state.osc_visible = false end
            state.anistart = nil
            state.animation = nil
            state.anitype =  nil
        end
    else
        state.anistart = nil
        state.animation = nil
        state.anitype =  nil
    end

    -- actual rendering
    local ass = assdraw.ass_new()

    -- Messages
    render_message(ass)

    -- actual OSC
    if state.osc_visible then
        render_elements(ass)
    end

    -- submit
    local w, h, aspect = mp.get_screen_size()
    mp.set_osd_ass(osc_param.playresy * aspect, osc_param.playresy, ass.text)

    -- set mouse area
    local area_y0, area_y1
    if user_opts.valign > 0 then
        -- deadzone above OSC
        area_y0 = get_align(-1 + (2*user_opts.deadzonesize), osc_param.posY - (osc_param.osc_h / 2), 0, 0)
        area_y1 = osc_param.playresy
    else
        -- deadzone below OSC
        area_y0 = 0
        area_y1 = (osc_param.posY + (osc_param.osc_h / 2))
         + get_align(1 - (2*user_opts.deadzonesize), osc_param.playresy - (osc_param.posY + (osc_param.osc_h / 2)), 0, 0)
    end

    --mouse show/hide area
    mp.set_mouse_area(0, area_y0, osc_param.playresx, area_y1, "showhide")

    --mouse input area
    if state.osc_visible then -- activate only when OSC is actually visible
        mp.set_mouse_area(
            osc_param.posX - (osc_param.osc_w / 2), osc_param.posY - (osc_param.osc_h / 2),
            osc_param.posX + (osc_param.osc_w / 2), osc_param.posY + (osc_param.osc_h / 2),
            "input")
        mp.enable_key_bindings("input")
    else
        mp.disable_key_bindings("input")
    end

end

--
-- Eventhandling
--

function process_event(source, what)

    if what == "down" then

        for n = 1, #elements do

            if not (elements[n].eventresponder == nil) then
                if not (elements[n].eventresponder[source .. "_up"] == nil) or not (elements[n].eventresponder[source .. "_down"] == nil) then

                    if mouse_hit(elements[n]) then
                        state.active_element = n
                        state.active_event_source = source
                        -- fire the down event if the element has one
                        if not (elements[n].eventresponder[source .. "_" .. what] == nil) then
                            elements[n].eventresponder[source .. "_" .. what](elements[n])
                        end
                    end
                end

            end
        end

    elseif what == "up" then

        if not (state.active_element == nil) then

            local n = state.active_element

            if n == 0 then
                --click on background (does not work)
            elseif n > 0 and not (elements[n].eventresponder[source .. "_" .. what] == nil) then

                if mouse_hit(elements[n]) then
                    elements[n].eventresponder[source .. "_" .. what](elements[n])
                end
            end
        end
        state.active_element = nil
        state.mouse_down_counter = 0
        state.last_seek = nil

    elseif source == "mouse_move" then
        local mouseX, mouseY = mp.get_mouse_pos()
        if (user_opts.minmousemove == 0) or
            (not ((state.last_mouseX == nil) or (state.last_mouseY == nil)) and
                ((math.abs(mouseX - state.last_mouseX) >= user_opts.minmousemove)
                    or (math.abs(mouseY - state.last_mouseY) >= user_opts.minmousemove)
                )
            ) then
            show_osc()
        end
        state.last_mouseX, state.last_mouseY = mouseX, mouseY

        if not (state.active_element == nil) then

            local n = state.active_element

            if not (elements[n].eventresponder == nil) then
                if not (elements[n].eventresponder[source] == nil) then
                    elements[n].eventresponder[source](elements[n])
                end
            end
        end
        tick()
    end
end

-- called by mpv on every frame
function tick()
    if (mp.get_property("fullscreen") == "yes" and user_opts.showfullscreen) or (mp.get_property("fullscreen") == "no" and user_opts.showwindowed) then
        render()
    else
        mp.set_osd_ass(osc_param.playresy, osc_param.playresy, "")
    end
end

function enable_osc(enable)
    if enable then
        mp.enable_key_bindings("showhide")
        show_osc()
    else
        hide_osc()
        mp.disable_key_bindings("showhide")
    end
end

mp.register_event("tick", tick)
mp.register_event("start-file", request_init)
mp.register_event("tracks-changed", request_init)

mp.register_script_message("enable-osc", function() enable_osc(true) end)
mp.register_script_message("disable-osc", function() enable_osc(false) end)

-- mouse show/hide bindings
mp.set_key_bindings({
    {"mouse_move",              function(e) process_event("mouse_move", nil) end},
    {"mouse_leave",             mouse_leave},
}, "showhide")
mp.enable_key_bindings("showhide", "allow-vo-dragging|allow-hide-cursor")

--mouse input bindings
mp.set_key_bindings({
    {"mouse_btn0",              function(e) process_event("mouse_btn0", "up") end,
                                function(e) process_event("mouse_btn0", "down")  end},
    {"shift+mouse_btn0",        function(e) process_event("shift+mouse_btn0", "up") end,
                                function(e) process_event("shift+mouse_btn0", "down")  end},
    {"mouse_btn2",              function(e) process_event("mouse_btn2", "up") end,
                                function(e) process_event("mouse_btn2", "down")  end},
    {"mouse_btn0_dbl",          "ignore"},
    {"shift+mouse_btn0_dbl",    "ignore"},
    {"mouse_btn2_dbl",          "ignore"},
    {"del",                     function() enable_osc(false) end}
}, "input", "force")
mp.enable_key_bindings("input")