#!/usr/bin/env bash
# shellcheck disable=SC2068,SC2162,SC2317 source=/dev/null

# Enable debug output to see what's happening
# set -x
set -o pipefail

####################################################################################
##
##  Purpose: Build FFmpeg from source code with addon libraries which are
##           also compiled from source to help ensure the latest functionality
##           possible
##
##  GitHub: https://github.com/slyfox1186/ffmpeg-build-script
##
##  Script version: 4.3.1
##
##  Updated: 12.24.2025
##
##  CUDA SDK Toolkit version: 12.3.1
##
##  Supported Distros: Debian 12/13, Ubuntu 22.04/24.04, WSL
##                     (Zorin OS 17 and Linux Mint 21.x also work)
##
##  Supported architecture: x86_64
##
####################################################################################

if [[ "$EUID" -eq 0 ]]; then
    echo "You must run this script without root or sudo."
    exit 1
fi

# Define global variables
script_name="${0##*/}"
script_version="4.3.1"
script_dir="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"

# Keep build artifacts out of the repo root (prevents cleanup from deleting the repo).
# Override with BUILD_ROOT=/path/to/dir if desired.
repo_root="$script_dir"
cwd="${BUILD_ROOT:-"$repo_root/build"}"
mkdir -p "$cwd"
cd "$cwd" || exit 1

packages="$cwd/packages"
workspace="$cwd/workspace"
log_file="$cwd/build.log"

# Source shared utilities
source "$script_dir/scripts/shared-utils.sh"

# Print script banner
echo
box_out_banner "FFmpeg Build Script - v$script_version"

# Create output directories
mkdir -p "$packages" "$workspace"

# Ensure staging directories remain writable between runs
ensure_user_ownership "$packages" "$workspace"

# Automatically overwrite the log file each time
log_file="$cwd/build.log"
rm -f "$log_file"
touch "$log_file"


# PRINT THE SCRIPT OPTIONS
usage() {
    echo
    echo "Usage: $script_name [options]"
    echo
    echo "Options:"
    echo "  -h, --help                        Display usage information"
    echo "   --compiler=<gcc|clang>           Set the default CC and CXX compiler (default: gcc)"
    echo "  -b, --build                       Starts the build process"
    echo "  -c, --cleanup                     Remove all working dirs"
    echo "  -g, --google-speech               Enable Google Speech for audible error messages (google_speech must already be installed to work)."
    echo "  -j, --jobs <number>               Set the number of CPU threads for parallel processing"
    echo "  -l, --latest                      Force the script to build the latest version of dependencies if newer version is available"
    echo "  -n, --enable-gpl-and-non-free     Enable GPL and non-free codecs - https://ffmpeg.org/legal.html"
    echo "  -v, --version                     Display the current script version"
    echo
    echo "Example: bash $script_name --build --compiler=clang -j 8"
    echo
}

COMPILER_FLAG=""
CONFIGURE_OPTIONS=()
LATEST=false
NONFREE_AND_GPL=false
GOOGLE_SPEECH=false
DO_BUILD=false

while (("$#" > 0)); do
    case "$1" in
        -h|--help)
            usage
            exit 0
            ;;
        -v|--version)
            echo
            echo "The script version is: $script_version"
            exit 0
            ;;
        -n|--enable-gpl-and-non-free)
            CONFIGURE_OPTIONS+=("--enable-"{gpl,libsmbclient,libcdio,nonfree})
            NONFREE_AND_GPL=true
            shift
            ;;
        -b|--build)
            DO_BUILD=true
            shift
            ;;
        -c|--cleanup)
            cleanup
            shift
            exit 0
            ;;
        -g|--google-speech)
            GOOGLE_SPEECH=true
            shift
            ;;
        -l|--latest)
            LATEST=true
            shift
            ;;
        --compiler=gcc|--compiler=clang)
            COMPILER_FLAG="${1#*=}"
            shift
            ;;
        -j|--jobs)
            if [[ -z "${2:-}" ]]; then
                fail "Missing value for $1 (expected a number)."
            fi
            if [[ ! "$2" =~ ^[0-9]+$ ]] || [[ "$2" -lt 1 ]]; then
                fail "Invalid jobs value: '$2' (expected a positive integer)."
            fi
            build_threads="$2"
            shift 2
            ;;
        *)
            usage
            exit 1
            ;;
    esac
done

if ! "$DO_BUILD"; then
    usage
    exit 0
fi

if [[ -z "$build_threads" ]]; then
    # Set the available CPU thread and core count for parallel processing (speeds up the build process)
    build_threads=$(nproc --all)
fi

MAKEFLAGS="-j$build_threads"

if [[ -z "$COMPILER_FLAG" ]] || [[ "$COMPILER_FLAG" == "gcc" ]]; then
    CC="gcc"
    CXX="g++"
elif [[ "$COMPILER_FLAG" == "clang" ]]; then
    CC="clang"
    CXX="clang++"
else
    fail "Invalid compiler specified. Valid options are 'gcc' or 'clang'."
fi
export CC CXX MAKEFLAGS
export LATEST NONFREE_AND_GPL
export GOOGLE_SPEECH

# Set ACLOCAL_PATH to include workspace m4 files
export ACLOCAL_PATH="$workspace/share/aclocal:/usr/share/aclocal"

echo
log "Utilizing $build_threads CPU threads"
echo

if "$NONFREE_AND_GPL"; then
    warn "With GPL and non-free codecs enabled"
    echo
fi


[[ -t 1 ]] && clear

# Validate sudo credentials once up front (many steps require sudo for installs).
require_sudo

# Initialize system setup (OS detection, package installation, etc.)
source "$script_dir/scripts/system-setup.sh"
initialize_system_setup

# Initialize hardware detection and CUDA setup
source "$script_dir/scripts/hardware-detection.sh" 
initialize_hardware_detection

# Prompt the user to install the GeForce CUDA SDK-Toolkit
install_cuda

# Update the ld linker search paths
sudo ldconfig

# Install Global Tools
source "$script_dir/scripts/global-tools.sh"
install_global_tools

# Install Core Libraries
source "$script_dir/scripts/core-libraries.sh"
install_core_libraries

# Install Support Libraries
source "$script_dir/scripts/support-libraries.sh"
install_miscellaneous_libraries

# Install Audio Libraries
source "$script_dir/scripts/audio-libraries.sh"
install_audio_libraries

# Install Video Libraries  
source "$script_dir/scripts/video-libraries.sh"
install_video_libraries

# Install Image Libraries
source "$script_dir/scripts/image-libraries.sh"
install_image_libraries

# Build FFmpeg
source "$script_dir/scripts/ffmpeg-build.sh"
build_ffmpeg