-- anime_sort.lua — a Naut-Torrent script that files each anime episode into a
-- tidy library as it finishes downloading:
--
--     <SORTED_ROOT>/<Anime Title>/Season NN/<Anime Title> - SNNENN.<ext>
--
-- It parses the filename with an embedded Anitomy-style parser (anime title,
-- season, episode) and asks the daemon to relocate the completed file via
-- naut.move_file(). Because Naut-Torrent fires on_file_complete the instant a
-- file's last piece verifies, episodes are sorted the moment they're done —
-- without waiting for the rest of the torrent.
--
-- Install:
--   nautd --socket /tmp/nautd.sock --script examples/anime_sort.lua
--   nautctl --socket /tmp/nautd.sock add_torrent \
--     '{"torrent_id":1,"torrent":"show.torrent","root":"/downloads/1"}'
--
-- The parser below is a VERBATIM COPY of examples/anitomy.lua (the sandbox has
-- no `require`, so it must be inlined). Keep the two in sync; examples/
-- test_anime_sort.lua asserts they agree.

----------------------------------------------------------------------
-- CONFIG — edit these
----------------------------------------------------------------------

local SORTED_ROOT       = "/sorted"   -- destination library root
local ONLY_VIDEO        = true        -- skip non-video files (subs, nfo, samples)
local KEEP_ORIGINAL_NAME = false      -- true: keep the original filename;
                                      -- false: rename to "Title - SNNENN.ext"

----------------------------------------------------------------------
-- embedded anitomy parser (== examples/anitomy.lua)
----------------------------------------------------------------------

local anitomy = (function()
local M = {}

local VIDEO_EXT = {
    mkv=true, mp4=true, avi=true, ogm=true, wmv=true, mov=true, flv=true,
    webm=true, m4v=true, mpg=true, mpeg=true, ts=true, m2ts=true, rmvb=true,
}

local KEYWORD = {}
for _, w in ipairs({
    "bd","bdrip","bdremux","bluray","blu-ray","dvd","dvdrip","dvd5","dvd9",
    "web","webrip","web-dl","webdl","hdtv","tvrip","hdrip","remux","hr",
    "x264","x265","h264","h265","h.264","h.265","hevc","avc","xvid","divx",
    "vp9","10bit","10bits","10-bit","8bit","hi10p","hi10",
    "aac","ac3","eac3","flac","dts","dts-hd","opus","mp3","truehd","aacx2",
    "flacx2","2.0","2.1","5.1","7.1","2ch","6ch",
    "dual","dualaudio","multi","multisubs","eng","engsub","jpn","jap","ita",
    "esp","vostfr","vf","raw","sub","subs","subbed","softsub","softsubs",
    "hardsub","hardsubs","dub","dubbed",
    "uncensored","censored","batch","repack","proper","internal","final",
    "ncop","nced","menu","preview",
}) do KEYWORD[w] = true end

local ORDINAL = { st=true, nd=true, rd=true, th=true }

local function splitext(name)
    local base, ext = name:match("^(.*)%.([%w]+)$")
    if base and #ext <= 4 then return base, ext:lower() end
    return name, nil
end

local function is_resolution(t)
    return t:match("^%d+[pi]$") ~= nil
        or t:match("^%d+[xX]%d+$") ~= nil
        or t:match("^[24][kK]$") ~= nil
end

local function is_crc(t)
    return #t == 8 and t:match("^%x+$") ~= nil and t:match("%a") ~= nil
end

local function is_junk(t)
    local low = t:lower()
    return KEYWORD[low] or is_resolution(t) or is_crc(t)
end

local function tokenize(s)
    local out = {}
    for tok in s:gmatch("%S+") do out[#out + 1] = tok end
    return out
end

local function extract(toks)
    local n = #toks
    local season, episode, episode_end, e_idx, s_idx

    for i = 1, n do
        local s, e = toks[i]:match("^[Ss](%d+)[Ee](%d+)$")
        if s then
            local _, e2 = toks[i]:match("[Ee](%d+)[%-~][Ee]?(%d+)$")
            return tonumber(s), tonumber(e), e2 and tonumber(e2) or nil, i
        end
    end

    for i = 1, n do
        local t = toks[i]
        if t:match("^[Ss]eason$") and toks[i + 1] and toks[i + 1]:match("^%d+$") then
            season, s_idx = tonumber(toks[i + 1]), i
            break
        end
        local num, ord = t:match("^(%d+)(%a%a)$")
        if num and ORDINAL[ord:lower()] and toks[i + 1]
           and toks[i + 1]:match("^[Ss]eason$") then
            season, s_idx = tonumber(num), i
            break
        end
        local sn = t:match("^[Ss](%d+)$")
        if sn and i > 1 then
            season, s_idx = tonumber(sn), i
            break
        end
    end

    for i = 1, n do
        local t = toks[i]
        local ep, epend
        local m = t:match("^[Ee](%d+)$") or t:match("^[Ee][Pp]%.?(%d+)$")
               or t:match("^[Ee]pisode(%d+)$") or t:match("^#(%d+)$")
        if m then ep = tonumber(m) end
        if not ep then
            local v = t:match("^(%d+)[vV]%d+$")
            if v then ep = tonumber(v) end
        end
        if not ep then
            local a, b = t:match("^(%d+)[%-~](%d+)$")
            if a then ep, epend = tonumber(a), tonumber(b) end
        end
        if not ep and (t:lower() == "ep" or t:lower() == "episode"
                       or t == "#") and toks[i + 1]
           and toks[i + 1]:match("^%d+$") then
            ep = tonumber(toks[i + 1])
        end
        if not ep and t:match("^%d+$") and i > 1 and toks[i - 1] == "-" then
            ep = tonumber(t)
        end
        if ep ~= nil then
            episode, episode_end, e_idx = ep, epend, i
        end
    end

    if episode == nil then
        for i = n, 1, -1 do
            local t = toks[i]
            if t == "-" then
                -- skip trailing dashes
            elseif t:match("^%d+$") then
                local num = tonumber(t)
                local year = (#t == 4 and num >= 1900 and num <= 2099)
                if i > 1 and not year and num > 0 then
                    episode, e_idx = num, i
                end
                break
            else
                break
            end
        end
    end

    local cut
    if e_idx then cut = e_idx end
    if s_idx and (not cut or s_idx < cut) then cut = s_idx end
    if episode ~= nil and season == nil then season = 1 end
    return season, episode, episode_end, cut
end

local function build_title(toks, cut)
    local last = (cut and cut - 1) or #toks
    local parts = {}
    for i = 1, last do
        local t = toks[i]
        if not is_junk(t) then parts[#parts + 1] = t end
    end
    while #parts > 0 and parts[#parts]:match("^[%-~:_]+$") do
        parts[#parts] = nil
    end
    local year
    if #parts > 1 then
        local y = parts[#parts]:match("^([12]%d%d%d)$")
        if y and tonumber(y) >= 1900 and tonumber(y) <= 2099 then
            year = tonumber(y)
            parts[#parts] = nil
            while #parts > 0 and parts[#parts]:match("^[%-~:_]+$") do
                parts[#parts] = nil
            end
        end
    end
    local title = table.concat(parts, " ")
    title = title:gsub("%s+", " "):gsub("^%s+", ""):gsub("%s+$", "")
    return title, year
end

function M.is_video(ext)
    return ext ~= nil and VIDEO_EXT[ext:lower()] == true
end

function M.parse(filename)
    local base, ext = splitext(filename)
    local release = base:match("^%s*%[(.-)%]") or base:match("^%s*%((.-)%)")
    local resolution = base:match("(%d+[pi])%f[%A]") or base:match("(%d+[xX]%d+)")
    local work = base:gsub("%b[]", " "):gsub("%b()", " "):gsub("%b{}", " ")
    work = work:gsub("[_]", " ")
    if not work:find(" ") and work:find("%.") then
        work = work:gsub("%.", " ")
    end
    work = work:gsub("%s+", " "):gsub("^%s+", ""):gsub("%s+$", "")

    local toks = tokenize(work)
    local season, episode, episode_end, cut = extract(toks)
    local title, year = build_title(toks, cut)
    if title == "" then title = release or "Unknown" end

    return {
        title=title, season=season, episode=episode, episode_end=episode_end,
        year=year, release_group=release, resolution=resolution,
        extension=ext, file_name=filename,
    }
end

return M
end)()

----------------------------------------------------------------------
-- path helpers
----------------------------------------------------------------------

local function basename(path)
    return path:match("[^/]+$") or path
end

-- Make a path component safe: drop characters that are illegal or awkward on
-- common filesystems, collapse whitespace, and trim.
local function sanitize(s)
    s = s:gsub('[<>:"/\\|%?%*%c]', "")
    s = s:gsub("%s+", " "):gsub("^%s+", ""):gsub("%s+$", "")
    if s == "" then s = "Unknown" end
    return s
end

local function destination(parsed)
    local title = sanitize(parsed.title)
    local ext = parsed.extension and ("." .. parsed.extension) or ""
    local original = sanitize(basename(parsed.file_name))

    if parsed.episode == nil then
        -- movie / special: <root>/<title>/<file>
        local fname
        if KEEP_ORIGINAL_NAME then
            fname = original
        else
            fname = title .. (parsed.year and (" (" .. parsed.year .. ")") or "") .. ext
        end
        return SORTED_ROOT .. "/" .. title .. "/" .. fname
    end

    local season = parsed.season or 1
    local sdir = string.format("Season %02d", season)
    local fname
    if KEEP_ORIGINAL_NAME then
        fname = original
    else
        fname = string.format("%s - S%02dE%02d", title, season, parsed.episode)
        if parsed.episode_end then
            fname = fname .. string.format("-E%02d", parsed.episode_end)
        end
        fname = fname .. ext
    end
    return SORTED_ROOT .. "/" .. title .. "/" .. sdir .. "/" .. fname
end

-- exposed for tests; harmless in the daemon
_G.anime_sort = { anitomy = anitomy, destination = destination }

----------------------------------------------------------------------
-- event hook
----------------------------------------------------------------------

function on_file_complete(event)
    if not event.path then return end
    local name = basename(event.path)
    local parsed = anitomy.parse(name)

    if ONLY_VIDEO and not anitomy.is_video(parsed.extension) then
        return  -- leave subtitles, .nfo, samples, etc. where they are
    end

    local dest = destination(parsed)
    local ok, err = pcall(naut.move_file, event.torrent_id, event.index, dest)
    if ok then
        print(string.format("[anime_sort] %s  ->  %s", name, dest))
    else
        print(string.format("[anime_sort] could not queue move for %s: %s",
                            name, tostring(err)))
    end
end

function on_torrent_finished(event)
    print(string.format("[anime_sort] torrent %d finished", event.torrent_id))
end