#!/usr/bin/env bash

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

if [[ $1 == "" ]]; then
    printf "\n${BOLD}Usage: $0 <filename> <optional crf value> <optional output name>\n - If you want to encode a range of CRF values then use -1 as the crf value.${NORMAL}\n"
    exit 1
fi

filename=$(basename -- "$1")
extension="${filename##*.}"
filename="${filename%.*}"

use_crf=$2
default_crf=25 # Programming vids have pretty crisp text @ crf 25.

output_name="$3"

function encode() {
    crf=$1
    if [[ $output_name == "" ]]; then
        output="${filename}_REDUCED_CRF-${crf}.$extension"
    else
        output="${output_name}.$extension"
    fi

    printf "\n${YELLOW}${BOLD}Encoding with crf $crf | output: $output${NORMAL}\n"
    ffmpeg -i "$filename.$extension" -c:v libx264 -crf $crf -preset veryfast -profile:v baseline -level 3.0 -strict -2 "$output"
    printf "\n${GREEN}${BOLD}Done encoding with crf $crf${NORMAL}\n\n"
}


if [[ $use_crf == "" ]]; then
    use_crf=$default_crf
fi

if [[ $use_crf == -1 ]]; then
    printf "\n${YELLOW}${BOLD}Encoding using a range of crf values.${NORMAL}\n"

    # Bigger crf values == bigger compression.
    for crf in {25..28}
    do
        encode $crf
    done
else
    encode $use_crf
fi