#!/usr/bin/env bash

if [ "$#" -ne 2 ]; then
  echo "Uso: $0 <input_file> <output_dir>"
  exit 1
fi

INPUT="$1"
OUTDIR="$2"

# Controlli preliminari
if [ ! -f "$INPUT" ]; then
  echo "Errore: file di input non trovato: $INPUT"
  exit 2
fi

# Crea la directory di output se non esiste
mkdir -p "$OUTDIR"
chmod 0755 "$OUTDIR"

# Evita che ffmpeg appenda a playlist esistenti accidentalmente
MASTER="${OUTDIR%/}/master.m3u8"
if [ -f "$MASTER" ]; then
  echo "Attenzione: master.m3u8 esistente verrà sovrascritto: $MASTER"
fi

# Comando ffmpeg per VOD: mantiene tutti i segmenti (-hls_list_size 0) e non cancella nulla
ffmpeg -hide_banner -y \
 -i "$INPUT" \
 -c:v libx264 -profile:v high -level 4.1 -preset veryfast -tune zerolatency \
 -b:v 5000k -maxrate 6000k -bufsize 12000k \
 -r 30 -g 90 -keyint_min 90 -sc_threshold 0 -x264-params "nal-hrd=cbr" \
 -pix_fmt yuv420p \
 -c:a aac -b:a 160k -ac 2 -ar 48000 \
 -f hls \
 -hls_time 3 -hls_list_size 0 -hls_playlist_type vod \
 -hls_segment_type mpegts \
 -hls_segment_filename "${OUTDIR%/}/segment_%05d.ts" \
 "${MASTER}"