#!/usr/bin/env bash
# Montaz lokalny, bez API. N przejsc zajmuje 10 s, potem 2 s najazdu, 6 s makro i 2 s planszy.
# INPUT/transition-1.mp4 ... transition-N.mp4 (kazdy >= 5 s), push.mp4 (>= 2 s), macro.mp4 (>= 6 s), outro.png.
set -euo pipefail
input=${1:?Podaj katalog wejscia}
output=${2:?Podaj plik wyjsciowy mp4}
n=${3:-3}
[[ "$n" =~ ^[1-9][0-9]*$ ]] && (( n <= 10 )) || { echo 'N musi wynosic 1-10' >&2; exit 1; }
input=$(cd "$input" && pwd)
output_dir=$(dirname "$output")
mkdir -p "$output_dir"
output="$(cd "$output_dir" && pwd)/$(basename "$output")"
[[ ! -e "$output" ]] || { echo 'Plik wyjsciowy juz istnieje' >&2; exit 1; }
workdir=$(mktemp -d)
# Bez kasowania rekursywnego; tymczasowe pliki sa male i zostaja do kontroli.
printf 'Pliki robocze: %s\n' "$workdir"
font=${FONT_FILE:-C:/Windows/Fonts/arial.ttf}
cp "$font" "$workdir/font.ttf"
for name in years title tagline; do
  if [[ -f "$input/$name.txt" ]]; then cp "$input/$name.txt" "$workdir/$name.txt"; else printf '%s' "$name" > "$workdir/$name.txt"; fi
done
args=()
for ((i=1;i<=n;i++)); do args+=(-i "$input/transition-$i.mp4"); done
args+=(-i "$input/push.mp4" -i "$input/macro.mp4" -loop 1 -i "$input/outro.png")
cd "$workdir"
filter=''
for ((i=0;i<n;i++)); do
  filter+="[$i:v]trim=duration=5,setpts=(PTS-STARTPTS)*2/$n,fps=30,scale=1080:1920:force_original_aspect_ratio=decrease,pad=1080:1920:(ow-iw)/2:(oh-ih)/2:color=0xF2EFE8,setsar=1,format=yuv420p[v$i];"
done
filter+="[$n:v]trim=duration=2,setpts=PTS-STARTPTS,fps=30,scale=1080:1920:force_original_aspect_ratio=decrease,pad=1080:1920:(ow-iw)/2:(oh-ih)/2:color=0xF2EFE8,setsar=1,format=yuv420p[push];"
filter+="[$((n+1)):v]trim=duration=6,setpts=PTS-STARTPTS,fps=30,scale=1080:1920:force_original_aspect_ratio=decrease,pad=1080:1920:(ow-iw)/2:(oh-ih)/2:color=0xF2EFE8,setsar=1,format=yuv420p[macro];"
filter+="[$((n+2)):v]trim=duration=2,setpts=PTS-STARTPTS,fps=30,scale=1080:1920:force_original_aspect_ratio=decrease,pad=1080:1920:(ow-iw)/2:(oh-ih)/2:color=0x08080A,setsar=1,format=yuv420p[outro];"
for ((i=0;i<n;i++)); do filter+="[v$i]"; done
filter+="[push][macro][outro]concat=n=$((n+3)):v=1:a=0,drawbox=x=80:y=600:w=920:h=2:color=0xA47940:t=fill:enable='lt(t,10)',drawtext=fontfile=font.ttf:textfile=years.txt:expansion=none:fontsize=36:fontcolor=0x594E3D:x='(w-text_w)/2-15*t':y=540:enable='lt(t,10)',drawtext=fontfile=font.ttf:textfile=title.txt:expansion=none:fontsize=42:fontcolor=0x594E3D:x=(w-text_w)/2:y=250:enable='between(t,12,18)',drawtext=fontfile=font.ttf:textfile=tagline.txt:expansion=none:fontsize=42:fontcolor=white:x=(w-text_w)/2:y=1450:enable='gte(t,18)'[out]"
# Parametry tekstu pochodza z plikow UTF-8, nie sa interpolowane w filtrze.
ffmpeg -hide_banner -loglevel error -filter_complex_threads 1 "${args[@]}" -filter_complex "$filter" -map '[out]' -an -t 20 -c:v libx264 -preset fast -crf 18 -pix_fmt yuv420p -movflags +faststart "$output"
ffprobe -v error -select_streams v:0 -show_entries stream=width,height,r_frame_rate -show_entries format=duration -of json "$output"