Angel Beats! Insert 4 FX

-- This script is made by FichteFoll for Akatsuki-subs
-- You can see this FX in Angel Beats episode 05 (BD version)

--[[
    Remarks
]]

include("karaskel.lua")

script_name = "AB ins4 FX"
script_description = "some effects"
script_author = "FichteFoll"
script_version = 1.0

-- ############################# handler funcs ##############################

function macro_script_handler(subs)
    aegisub.progress.title(script_name);
    script_handler(subs)
    aegisub.set_undo_point("\""..script_name.."\"")
end

function script_handler(subs)
    aegisub.progress.task("Getting header data...")
    generate_styles(subs)
    local meta, styles = karaskel.collect_head(subs, false)

    undo_fx(subs)

    aegisub.progress.task("Applying effect...")
    local i, maxi = 1, #subs
    for i = 1, maxi do
        if aegisub.progress.is_cancelled() then error("User cancelled") end
        aegisub.progress.task(string.format("Applying effect (%d/%d)...", i, maxi))
        aegisub.progress.set((i-1)/maxi*100)
        local l = subs[i]

        if (l.class == "dialogue" and not l.comment) or (l.class == "dialogue" and l.comment and l.effect == "karaoke") then
            do_fx(subs, meta, styles, l)
            l.comment = true
            l.effect = "karaoke"
            subs[i] = l
        end

        i = i + 1
    end

    aegisub.progress.task("Finished!")
    aegisub.progress.set(100)
end


function undo_macro_script_handler(subs)
    aegisub.progress.title("Undo "..script_name);
    undo_fx(subs)
    aegisub.set_undo_point("\"Undo "..script_name.."\"")
end

-- ############################# fx funcs ############################## -- action begins here
local li = 0
local sub_start, kanji_start = false, false

function do_fx(subs, meta, styles, baseline)
    local line = table.copy(baseline)
    li = li + 1

    -- variables
    local fade_min, fade_max, fadein_accel = 700, 2000, 3
    local _line = {
                fadein = {
                    mindur = fade_min,
                    maxdur = fade_max,
                    accel = fadein_accel;
                },
                fadeout = {
                    mindur = fade_min,
                    maxdur = fade_max,
                    accel = 1.0/fadein_accel;
                },
                color = {},
                alpha = {};
            }
    local _syl = {
                hl = {
                    fadein = {
                        dur = 50,
                        accel = 0.4;
                    };
                    fadeout = {
                        mindur = 800,
                        multi = 1.5,
                        ymulti = 3,
                        movemulti = 6.0;
                    };
                };
                start_off = 0,
                end_off = 0,
                noblank = {n = 0};
            }

    for i, c, a in colors_from_style(styles[line.style]) do
        _line.color[i] = c
        _line.alpha[i] = a
    end

    -- generate positions
    if not kanji_start and line.style:find("kanji") then
        kanji_start = true
        li = 1
    end
    if not sub_start and line.style:find("english") then
        sub_start = true
        li = 1
    end

    if (line.actor:find("overlay") and line.actor:find("start")) then li = li-1 end
    local left = (li % 2 == 0)

    if not (line.style == "ins4_romaji" or line.style == "ins4_romaji-blue") then
        if line.style:find("english") and not line.actor:find("bg") then left = not left; end

        if left then
            line.style = line.style.."-left"
        else
            line.style = line.style.."-right"
        end
        if line.style:find("english") and not line.actor:find("bg") then left = not left; end -- reverse change to let syllables fly into the same direction
    end

    local si = 0

    if (line.style:find("ins4_romaji") or line.style:find("ins4_kanji") or line.style:find("ins4_english")) then

        -- generate syls for non-karaoke part
        if line.style:find("ins4_english") then
            local ltext, ltext_stripped = "", strip_comments(line.text)
            for word in ltext_stripped:words() do -- to generate positions for each word
                _syl.noblank.n = _syl.noblank.n + 1
                _syl.noblank[_syl.noblank.n] = string.format("{\\k1}%s ", word)
                ltext = string.format("%s{\\k1}%s ", ltext, word)
            end
            line.text = ltext
        end

        -- karaoke
        karaskel.preproc_line(subs, meta, styles, line)
        line.effect = "fx" -- affects all copies from line
        line.layer = 2

        for i = 1, line.kara.n do
            local syl = line.kara[i]
            if (syl.duration > 0 and syl.text_stripped ~= '' and syl.text_stripped ~= ' ') then
                _syl.noblank.n = _syl.noblank.n + 1
                _syl.noblank[_syl.noblank.n] = syl
            end
        end


        -- For every syl
        for i = 1, line.kara.n do
            local syl = line.kara[i]

            if (syl.duration > 0 and syl.text_stripped ~= '' and syl.text_stripped ~= ' ') then
                si = si + 1
                local l

                -- fade-in
                l = table.copy(line)
                local maxmovex, maxmovey = line.styleref.fontsize*3, -line.styleref.fontsize*3
                local minmovex, minmovey = line.styleref.fontsize, -line.styleref.fontsize
                if left then maxmovex = maxmovex * -1; minmovex = minmovex * -1; end

                if not line.actor:find("start") then
                    local temp, colnum = "{\\an5\\move(%%f,%%f,%%f,%%f)}{\\alpha&HFF&\\t(%f,\\1a%s\\3a%s\\4a%s)}{\\frx%%f\\fry%%f\\frz%%f\\t(\\frx0\\fry0\\frz0)}{\\c%s}%s", 2
                    if line.style:find("ins4_english") then colnum = 1 end

                    temp = string.format(temp, _line.fadein.accel, _line.alpha[colnum], _line.alpha[3], _line.alpha[4], _line.color[colnum], syl.text_stripped)
                    l.text = string.format(temp, line.left+syl.center + math.random()*(maxmovex-minmovex)+minmovex, line.middle + math.random()*(maxmovey-minmovey)+minmovey, line.left+syl.center, line.middle,
                            math.random(-360,360), math.random(-360,360), math.random(-70,70))

                    l.start_time = line.start_time - math.random(_line.fadein.mindur, _line.fadein.maxdur)
                    l.end_time = line.start_time
                    subs.append(l)
                end

                -- fade-out
                if not line.actor:find("end") then
                    l = table.copy(line)
                    minmovex = minmovex * -1; maxmovex = maxmovex * -1;
                    minmovey = minmovey * -1; maxmovey = maxmovey * -1;

                    local temp = string.format("{\\an5\\move(%%f,%%f,%%f,%%f)}{\\t(%f,\\alpha&HFF&)}{\\t(\\frx%%f\\fry%%f\\frz%%f}%s", _line.fadein.accel, syl.text_stripped)
                    l.text = string.format(temp, line.left+syl.center, line.middle,
                            line.left+syl.center + math.random()*(maxmovex-minmovex)+minmovex, line.middle + math.random()*(maxmovey-minmovey)+minmovey,
                            math.random(-360,360), math.random(-360,360), math.random(-70,70))

                    l.start_time = line.end_time
                    l.end_time = line.end_time + math.random(_line.fadein.mindur, _line.fadein.maxdur)
                    subs.append(l)
                end
            end
        end

        -- Highlight effect
        local show, hide, temp = tonumber(line.actor:match("start:(%d+)")), tonumber(line.actor:match("end:(%d+)")), ""
        if show and show > 0 then temp = string.format("{\\alpha&HFF&\\t(%d,%d,\\alpha&H00&)}", show, show) end
        if hide and hide > 0 then temp = string.format("{\\t(%d,%d,\\alpha&HFF&)}", hide, hide) end

        if (line.style:find("ins4_romaji") or line.style:find("ins4_kanji")) then
            l = table.copy(line)
            l.text = string.format("{\\an5\\pos(%f,%f)}%s%s", line.center, line.middle, temp, line.text)
            subs.append(l)
        elseif line.style:find("ins4_english") then
            l = table.copy(line)
            l.text = string.format("{\\an5\\pos(%f,%f)}%s%s", line.center, line.middle, temp, baseline.text)
            subs.append(l)
        end
--~         local l = table.copy(line)
--~         if (line.style:find("ins4_romaji") or line.style:find("ins4_kanji")) then
--~             subs.append(l)
--~         end
    end
end

-- Collect and generate styles
function generate_styles(subs)
    local styles = {n = 0}
    local toinsert = {}
    local first_style_line, last_style_line = nil, nil

    -- First pass: collect all existing styles
    for i = 1, #subs do
        if aegisub.progress.is_cancelled() then error("User cancelled") end
        local l = subs[i]
        l.i = i

        if l.class == "style" and l.section == "[V4+ Styles]" then
            if not first_style_line then first_style_line = i end
            -- Store styles into the style table
            styles.n = styles.n + 1
            styles[styles.n] = l
            styles[l.name] = l
            l.margin_v = l.margin_t -- convenience

            -- Generate top-left and -right styles for all
            if l.name:find("^ins4_") and (not l.name:find("-left$") and not l.name:find("-right$")) then
                local fxs = table.copy(l)
                fxs.align = 7
                fxs.name = fxs.name .. "-left"
                table.insert(toinsert, fxs) -- queue to insert in file

                fxs = table.copy(l)
                fxs.align = 9
                fxs.name = fxs.name .. "-right"
                table.insert(toinsert, fxs) -- queue to insert in file
            end

        elseif first_style_line and not last_style_line then
            last_style_line = i
        end
    end

    -- Second pass: insert all toinsert styles that don't already exist
    for i = 1, #toinsert do
        if not styles[toinsert[i].name] then
            -- Insert into styles table
            styles.n = styles.n + 1
            styles[styles.n] = toinsert[i]
            styles[toinsert[i].name] = toinsert[i]
            -- And subtitle file
            subs[-(last_style_line)] = toinsert[i]
        else
            subs[styles[toinsert[i].name].i] = toinsert[i]
        end
    end
end

function undo_fx(subs)
    aegisub.progress.task("Unapplying effect...")

    local i, ai, maxi, maxai = 1, 1, #subs, #subs
    while i <= maxi do
        aegisub.progress.task(string.format("Unapplying effect (%d/%d)...", ai, maxai))
        aegisub.progress.set((ai-1)/maxai*100)
        local l = subs[i]
        if (l.class == "dialogue" and not l.comment and l.effect == "fx") then
            subs.delete(i)
            maxi = maxi - 1
        else
            if (l.class == "dialogue" and l.comment and l.effect == "karaoke") then
                l.comment = false
                l.effect = ''
                subs[i] = l
            end
            i = i + 1
        end
    end
end

-- ############################### helping funcs ##############################

function colors_from_style(style)
    local i = 0
    function enum_colors_from_style()
        i = i + 1
        if (i > 4) then
            return nil
        end

        return i, color_from_style(style["color"..tostring(i)]), alpha_from_style(style["color"..tostring(i)])
    end

    return enum_colors_from_style, nil, nil
end

function strip_comments(str)
    return str:gsub("{.-}", "")
end

-- ############################### validation funcs ##############################

function macro_validation(subs)
    for i = 1, #subs do
        local l = subs[i]
        if (l.class == "dialogue" and not l.comment) or (l.class == "dialogue" and l.comment and l.effect == "karaoke") then
            return true
        end
    end

    return false
end

aegisub.register_filter(script_name, "", 2000, script_handler)
aegisub.register_macro(script_name, "processing script as templater", macro_script_handler, macro_validation)