#!/usr/bin/env bash

# This is for reencoding a non-mp4 video to mp4 using an mpeg4 encoder.
# Can optionally compress the video.

if which tput >/dev/null 2>&1; then
    ncolors=$(tput colors)
fi
if [ -t 1 ] && [ -n "$ncolors" ] && [ "$ncolors" -ge 8 ]; then
    RED="$(tput setaf 1)"
    GREEN="$(tput setaf 2)"
    YELLOW="$(tput setaf 3)"
    BLUE="$(tput setaf 4)"
    MAGENTA="$(tput setaf 5)"
    CYAN="$(tput setaf 6)"
    BOLD="$(tput bold)"
    NORMAL="$(tput sgr0)"
else
    RED=""
    GREEN=""
    YELLOW=""
    BLUE=""
    MAGENTA=""
    CYAN=""
    BOLD=""
    NORMAL=""
fi

compress="$1"
filename="$2"
output_name="$3"
bitrate="$4"

if [[ $compress == "" || $filename == "" || $output_name == "" ]]; then
    printf "${BOLD}${RED}Usage: convert-video-to-mp4 <compress 1|0> <filename> <output name> <optional: bitrate, e.g. \"4000k\", defaults to source>${NORMAL}\n"
    exit 1
fi


filename=$(basename -- "$filename")
extension="${filename##*.}"
extension="${extension,,}"  # go lower-case
filename="${filename%.*}"

output="$output_name.mp4"

bitrate_args=""

if [[ $compress -eq 1 ]]; then
    temp_output="temp_$output"
else
    temp_output="$output"
fi

# convert first.
# we convert then compress instead of compressing on first pass because this results in a slightly higher bitrate.

cmd=""

if [[ $extension == "mkv" || $extension == "mpg" ]]; then
    if [[ $bitrate != "" ]]; then
        bitrate_args="-b:v $bitrate"
    else
        bitrate="<source value>"
    fi

    cmd="ffmpeg -y -stats -loglevel level+error -i \"$filename.$extension\" -vcodec copy -acodec copy $bitrate_args \"$temp_output\""

elif [[ $extension == "flv" ]]; then
    if [[ $bitrate == "" ]]; then
        bitrate="5M"
    fi
    bitrate_args="-b:v $bitrate"

    cmd="ffmpeg -y -stats -loglevel level+error -vsync 0 -hwaccel cuvid -c:v h264_cuvid -i \"$filename.$extension\" -c:a aac -c:v h264_nvenc $bitrate_args \"$temp_output\""

elif [[ $extension == "avi" || $extension == "wmv" ]]; then
    cmd="ffmpeg -y -stats -loglevel level+error -i \"$filename.$extension\" -c:a aac -c:v mpeg4 $bitrate_args \"$output\""

else
    printf "${BOLD}${RED}Don't know how to convert a '$extension' to mp4. Add support!${NORMAL}\n"
    exit 1
fi

printf "\n${YELLOW}${BOLD}Encoding '$filename.$extension' | compress: $compress | output: $output | bitrate: $bitrate${NORMAL}\n"

eval "$cmd"

if [[ $compress -eq 1 ]]; then
    compress-video 1 "$temp_output" "$output"
    rm "$temp_output"
else
    printf "\n"
fi

printf "${GREEN}${BOLD}Done encoding '$filename.$extension' to '$output'${NORMAL}\n\n"