#!/usr/bin/env bash
check_newgrounds() {
    online_page=$(curl -s "$line") || return 1;
    online_latest=$(grep -o '<meta property="og:description" content="Latest: '.* <<< "$online_page" | sed 's|<meta property="og:description" content="Latest: '\''||; s|'\''" />.*||;')
    online_title=$(grep '<title>.*</title>' <<< "$online_page" | sed 's|.*<title>||; s|'\''s Movies</title>.*||')
}
check_youtube() {
    online_page=$(curl -s "$line") || return 1;
    online_latest=$(grep -o '"text":"'[^}]*'"}],"' <<< "$online_page" | sed 's|^"text":"||; s|"}],"$||' | head -n1)
    online_title=$(grep -o "<title>.*</title>" <<< "$online_page" | sed 's|<title>||; s| - YouTube</title>||')
}
check_prawnhub() {
    online_page=$(curl -s "$line") || return 1;
    online_page_condensed=$(tr -d '\n' <<< "$online_page" | sed 's|\t| |g; s|  *| |g')
    online_latest=$(sed 's|.*"profileContent"||; s|.*"channelsBody"||; s|data-related-url.*||; s|.*title="||; s|" class.*||' <<< "$online_page_condensed")
    online_title=$(sed 's|.*<title>||; s|</title>.*|</title>|; s|Prawn Videos Uploaded by Prawnstar ||; s| &#124; Prawnhub</title>||; s|&#039;s Videos$||' <<< "$online_page_condensed")
}
remove_old_entry() {
    lineno=$(grep -n "$line" "$cachefile"|sed 's|:.*$||')
    sed -i "$lineno"'d' "$cachefile"
}
add_entry() {
    echo "$line|$online_latest|$today" >> "$cachefile"
    online_date="NEW!"
}

cachefile="channels_cache.txt"
[[ ! -f "$cachefile" ]] && touch "$cachefile"
today=$(date +%d-%m-%Y)
printf "%-15.15s %-15.15s %-75.75s\n" "[Author]" "[Updated]" "[Latest video]"
while read line; do

    # Get online version
    online_date="$today"
    if [[ "$line" == *"newgrounds.com"* ]]; then check_newgrounds;
    elif [[ "$line" == *"youtube.com"* ]]; then check_youtube;
    elif [[ "$line" == *"prawnhub.com"* ]]; then check_prawnhub;
    else
        printf "%s\n" "$line";
        continue;
    fi

    if [ "$?" = "1" ]; then
        printf "%-15.15s %-15.15s %-75.75s\n" "ERROR" "n/a" "Page could not be reached: $line"
        continue
    fi

    # Compare against local txt file
    if cached_page=$(grep "$line" "$cachefile"); then
        cache_date=$(cut -d\| -f3 <<< "$cached_page")
        cache_latest=$(cut -d\| -f2 <<< "$cached_page")
        if [[ "$cache_latest" = "$online_latest" ]]; then
            online_date="$cache_date"
        else
            remove_old_entry
            add_entry
        fi
    else
        add_entry
    fi

    printf "%-15.15s %-15.15s %-75.75s\n" "$online_title" "$online_date" "$online_latest"
done < "channels.txt"