create.sh

#!/usr/bin/env bash
# Program:
#     Convert your mp4 file to KDE Plasma splash screen
# 2025-12-07    Coldrain    Release 1.0.0

set -Eeuo pipefail

tmp_dir=""
work_created=0

log_info() {
    printf '[INFO] %s\n' "$1"
}

log_ok() {
    printf '[OK] %s\n' "$1"
}

log_error() {
    printf '[ERROR] %s\n' "$1" >&2
}

log_done() {
    printf '[DONE] %s\n' "$1"
}

cleanup() {
    if [[ -n "${tmp_dir:-}" && -d "$tmp_dir" ]]; then
        rm -rf "$tmp_dir"
    fi
}

handle_error() {
    local exit_code=$?
    log_error "exit=$exit_code at line $LINENO: $BASH_COMMAND"
    if [[ "$work_created" -eq 1 && -n "${work_path:-}" && -d "$work_path" ]]; then
        rm -rf "$work_path"
        log_info "Removed incomplete work directory: $work_path"
    fi
    exit "$exit_code"
}

trap cleanup EXIT
trap handle_error ERR

script_dir="$(cd -- "$(dirname -- "${BASH_SOURCE[0]}")" && pwd)"
template_path="$script_dir/template"
target_path="$HOME/.local/share/plasma/look-and-feel"

print_header() {
    printf '\n'
    printf '== ✨ Video to Plasma Splash Screen ✨ ==\n'
    printf '\n'
}

check_dependencies() {
    log_info "Checking dependencies..."
    for command_name in ffmpeg jq; do
        if ! command -v "$command_name" >/dev/null 2>&1; then
            log_error "'$command_name' is required but not installed."
            exit 1
        fi
        log_ok "$command_name"
    done
}

prompt_slug() {
    local prompt_text="$1"
    local value

    while true; do
        read -r -p "$prompt_text" value
        if [[ "$value" =~ ^[A-Za-z0-9._-]+$ ]]; then
            printf '%s\n' "$value"
            return
        fi
        log_error "Please use only letters, numbers, '.', '_' or '-'."
    done
}

prompt_existing_file() {
    local prompt_text="$1"
    local value

    while true; do
        read -r -p "$prompt_text" value
        if [[ "$value" == "exit" ]]; then
            log_info "Exit now."
            exit 0
        fi
        if [[ -f "$value" ]]; then
            printf '%s\n' "$value"
            return
        fi
        log_error "File not found. Please enter an existing file path."
    done
}

time_to_seconds() {
    local time_value="$1"
    local hours minutes seconds

    IFS=: read -r hours minutes seconds <<<"$time_value"
    printf '%d\n' "$((10#$hours * 3600 + 10#$minutes * 60 + 10#$seconds))"
}

prompt_time_range() {
    local value begin end begin_seconds end_seconds

    while true; do
        read -r -p "[4/7] Clip range (hh:mm:ss~hh:mm:ss, less than 5 seconds recommended): " value
        if [[ ! "$value" =~ ^[0-9]{2}:[0-9]{2}:[0-9]{2}~[0-9]{2}:[0-9]{2}:[0-9]{2}$ ]]; then
            log_error "Invalid format. Example: 00:00:00~00:00:04"
            continue
        fi

        begin="${value%%~*}"
        end="${value##*~}"
        begin_seconds="$(time_to_seconds "$begin")"
        end_seconds="$(time_to_seconds "$end")"

        if ((end_seconds <= begin_seconds)); then
            log_error "End time must be greater than begin time."
            continue
        fi

        printf '%s\n' "$value"
        return
    done
}

prompt_number() {
    local prompt_text="$1"
    local value

    while true; do
        read -r -p "$prompt_text" value
        if [[ "$value" =~ ^[0-9]+$ && "$value" -gt 0 ]]; then
            printf '%s\n' "$value"
            return
        fi
        log_error "Please enter a positive number."
    done
}

prompt_preview() {
    local choice

    while true; do
        printf '[7/7] Preview image:\n'
        printf '      1) Auto-generate from video\n'
        printf '      2) Use custom png\n'
        printf '      3) Skip\n'
        read -r -p "Choose [1/2/3] (default: 1): " choice
        choice="${choice:-1}"

        case "$choice" in
        1)
            preview_mode="auto"
            preview_path=""
            return
            ;;
        2)
            preview_path="$(prompt_existing_file "Preview png path: ")"
            preview_mode="custom"
            return
            ;;
        3)
            preview_mode="skip"
            preview_path=""
            return
            ;;
        *)
            log_error "Please choose 1, 2 or 3."
            ;;
        esac
    done
}

confirm_summary() {
    printf '\n'
    printf 'Generation summary:\n'
    printf '  Author:  %s\n' "$author_name"
    printf '  Work:    %s\n' "$work_name"
    printf '  Output:  %s\n' "$work_path"
    printf '  Video:   %s\n' "$video_path"
    printf '  Clip:    %s ~ %s\n' "$begin_time" "$end_time"
    printf '  FPS:     %s\n' "$fps"
    printf '  Width:   %s\n' "$scale_width"
    case "$preview_mode" in
    auto) printf '  Preview: auto-generate from video\n' ;;
    custom) printf '  Preview: %s\n' "$preview_path" ;;
    skip) printf '  Preview: skip\n' ;;
    esac
    printf '\n'

    read -r -p "Continue? [Y/n]: " confirm
    case "${confirm:-Y}" in
    y | Y | yes | YES) ;;
    *)
        log_info "Cancelled."
        exit 0
        ;;
    esac
}

write_metadata() {
    jq --arg author_name "$author_name" \
        --arg plugin_id "$new_name" \
        --arg plugin_name "$work_name" \
        '.KPlugin.Authors[0].Name = $author_name
        | .KPlugin.Id = $plugin_id
        | .KPlugin.Description = $plugin_name
        | .KPlugin.Name = $plugin_name' \
        "$work_path/metadata.json" >"$metadata_tmp"
    mv "$metadata_tmp" "$work_path/metadata.json"
}

write_preview() {
    case "$preview_mode" in
    auto)
        mkdir -p "$work_path/contents/previews"
        ffmpeg -i "$tmp_video" -frames:v 1 -loglevel quiet -hide_banner -y "$work_path/contents/previews/splash.png"
        log_ok "Preview image generated"
        ;;
    custom)
        mkdir -p "$work_path/contents/previews"
        cp "$preview_path" "$work_path/contents/previews/splash.png"
        log_ok "Preview image configured"
        ;;
    skip)
        log_info "Preview image skipped. You can add it later at '$work_path/contents/previews/splash.png'."
        ;;
    esac
}

print_header
check_dependencies

author_name="$(prompt_slug "[1/7] Author name: ")"
work_name="$(prompt_slug "[2/7] Work name: ")"
new_name="$author_name.$work_name"
work_path="$target_path/$new_name"

if [[ -e "$work_path" ]]; then
    log_error "'$work_path' already exists. Please remove it or choose another name."
    exit 1
fi

video_path="$(prompt_existing_file "[3/7] MP4 video path (enter 'exit' to exit): ")"
log_ok "Video found"

time_range="$(prompt_time_range)"
begin_time="${time_range%%~*}"
end_time="${time_range##*~}"
begin_seconds="$(time_to_seconds "$begin_time")"
end_seconds="$(time_to_seconds "$end_time")"
duration_seconds="$((end_seconds - begin_seconds))"

fps="$(prompt_number "[5/7] FPS (30~120 recommended): ")"
scale_width="$(prompt_number "[6/7] Width scale (1920 recommended): ")"
preview_mode=""
preview_path=""
prompt_preview

confirm_summary

tmp_dir="$(mktemp -d)"
tmp_video="$tmp_dir/tmp_video.mp4"
palette="$tmp_dir/palette.png"
metadata_tmp="$tmp_dir/metadata.json"

log_info "Creating theme directory..."
mkdir -p "$target_path"
cp -r "$template_path" "$work_path"
work_created=1
log_ok "Theme directory created"

log_info "Extracting video clip..."
ffmpeg -ss "$begin_time" -i "$video_path" -t "$duration_seconds" -c:v libx264 -c:a aac -loglevel quiet -hide_banner -y "$tmp_video"
log_ok "Video clip extracted"

log_info "Generating palette..."
ffmpeg -i "$tmp_video" -vf "fps=$fps,scale=$scale_width:-2:flags=lanczos,palettegen" -loglevel quiet -hide_banner -y "$palette"
log_ok "Palette generated"

log_info "Generating GIF..."
ffmpeg -i "$tmp_video" -i "$palette" -lavfi "fps=$fps,scale=$scale_width:-2:flags=lanczos[x];[x][1:v]paletteuse" -loglevel quiet -hide_banner -y "$work_path/contents/splash/images/$work_name.gif"
log_ok "GIF generated"

log_info "Writing theme metadata..."
write_metadata
sed -i "s/gif_file_here/$work_name/" "$work_path/contents/splash/Splash.qml"
log_ok "Theme metadata written"

write_preview

printf '\n'
log_done "Your splash screen has been created:"
printf '       %s\n' "$work_path"