Remember which episode you had watched

fiml.desktop

[Desktop Entry]
Type=Service
X-KDE-ServiceTypes=KonqPopupMenu/Plugin
MimeType=inode/directory;
Actions=fimlAction;
Icon=videoclip-amarok

[Desktop Action fimlAction]
Name=Fiml
Icon=videoclip-amarok
Exec=/path/to/fiml.sh "%u"

fiml.sh

#!/bin/bash

set -euo pipefail

dialog() {
    kdialog --title "fiml" "$@" 2>/dev/null
}

return-code() {
    local result=0
    "$@" || { result=$?; }
    echo ${result}
}

play-vlc() {
    local -r film="$1" sub="$2"
    local cmd=(vlc "${film}")
    if [[ -n "${sub}" ]]; then
        cmd+=(--sub-file "${sub}")
    fi
    "${cmd[@]}" >/dev/null 2>&1
}

find-by-ext() {
    local -r ext="$1"
    find -iname "*.${ext}" -print0
}

find-films() {
    { find-by-ext mp4; find-by-ext mkv; } | sort -z
}

find-subs() {
    find-by-ext srt | sort -z
}

find-and-set() {
    readarray -d '' films < <(find-films)
    readarray -d '' subs  < <(find-subs)
}

play-nth() {
    local -r n="$1"
    play-vlc "${films[$n]}" "${subs[$n]:-""}"
}

read-counter() {
    [[ -f ".fiml" ]] && counter=$(< ".fiml") || counter=0
}

write-counter() {
    echo ${counter} > ".fiml"
}

choose-film() {
    local radiopts=() toggle item
    for i in ${!films[@]}; do
        (( counter == i )) && toggle=on || toggle=off
        item="${films[$i]}"
        if [[ -n "${subs[$i]:-""}" ]]; then
            item="${item}    + subtitle"
        fi
        radiopts+=($i "${item}" ${toggle})
    done
    dialog --radiolist "Which episode?" "${radiopts[@]}"
}

ask-reset-counter() {
    local result
    result=$(return-code dialog --yesnocancel "Reset the counter?")
    if (( result == 2 )); then
        return 1
    elif (( result == 0 )); then
        counter="${selected}"
    fi
}

ask-complete-watch() {
    local result
    result=$(return-code dialog --yesno "Did you watch the episode?")
    if (( result == 0 )); then
        (( counter += 1 ))
    fi
}

main() {
    local path="$1"
    [[ -n "${path}" ]] || path="./"
    cd "${path}"
    find-and-set
    read-counter
    local selected
    selected="$(choose-film)"
    [[ -n "${selected}" ]] || exit
    (( selected == counter )) || ask-reset-counter || exit
    play-nth "${selected}"
    (( selected != counter )) || ask-complete-watch
    write-counter
}

main "$@"