#!/bin/bash

#Find the video file
video_path=$(find /usr/src/app/video -type f -name "*.mp4")

#Take the screenshot of the first frame of the video
ffmpeg -i $video_path -vframes 1 /usr/src/app/video/screenshot.png

#Get the list of of all frames resembling to the image with %85 ratio
ffmpeg -i $video_path -loop 1 -i /usr/src/app/video/screenshot.png -an -filter_complex "blend=difference:shortest=1,blackframe=85:32" -f null - > /usr/src/app/video/output.txt 2>&1

file='/usr/src/app/video/output.txt'
regex='t:([0-9\.]+)'
detected='/usr/src/app/video/detected.txt'

global_rematch() {
    local file=$1 regex=$2
    timeStamps=()
    while IFS= read -r line; do
        [[ $line =~ $regex ]]
        if [[ "${BASH_REMATCH[1]}" == "" ]]; then
            :
        else
            timeStamps+=("${BASH_REMATCH[1]}")
        fi
    done < $file
}


# Function to convert seconds to HH:MM:SS format using awk
seconds_to_hms() {
    local seconds=$1

    local hours=$(awk -v secs="$seconds" 'BEGIN { printf "%02d", int(secs / 3600) }')
    local minutes=$(awk -v secs="$seconds" 'BEGIN { printf "%02d", int((secs / 60) % 60) }')
    local seconds=$(awk -v secs="$seconds" 'BEGIN { printf "%06.3f", secs % 60 }')

    echo "$hours:$minutes:$seconds"
}

global_rematch "$file" "$regex" 

newTime=()

for ((i=1;i<${#timeStamps[@]};i++)); do
    if (( $(echo "${timeStamps[$i+1]}-${timeStamps[$i]} > 1" |bc -l) )); then
        newTime+=($(seconds_to_hms "${timeStamps[$i]}"))
        newTime+=($(seconds_to_hms "${timeStamps[$i+1]}"))
    fi
done

# Write array elements to file
for element in "${newTime[@]}"; do
    echo "$element" >> "$detected"
done

scene-time -i /usr/src/app/video/detected.txt -o /usr/src/app/video/cutlist.txt

scene-cut -i $video_path -c /usr/src/app/video/cutlist.txt

rm /usr/src/app/video/cutlist.txt /usr/src/app/video/detected.txt /usr/src/app/video/output.txt /usr/src/app/video/screenshot.png