#!/usr/bin/env bash
# Producer: the single entry point for VoiceForge. The first run bootstraps a
# fully contained runtime under lib/ (managed Python 3.13, dependencies,
# bundled FFmpeg, and later the AI environments and model weights); every run
# then executes the program from that runtime. Nothing is installed outside
# this directory: no PATH changes, no sudo, no system Python changes.
#
# Trust boundary for downloads: official PyPI (uv, application wheels) and
# Astral's managed CPython distribution. AI setup additionally trusts
# download.pytorch.org and the pinned DeepFilterNet3 model host. Host
# package-manager settings (extra indexes, targets, constraints, config
# files) cannot add to or redirect these sources.
#
# First bootstrap needs an existing `uv`, or a Python 3 with venv support.
# Later runs, including moving or renaming this whole directory, are handled
# by the launcher itself; caches make the repair fast.
set -euo pipefail

SOURCE="${BASH_SOURCE[0]}"
while [[ -L "$SOURCE" ]]; do
    DIR="$(CDPATH='' cd -- "$(dirname -- "$SOURCE")" && pwd)"
    SOURCE="$(readlink -- "$SOURCE")"
    [[ "$SOURCE" != /* ]] && SOURCE="$DIR/$SOURCE"
done
ROOT="$(CDPATH='' cd -- "$(dirname -- "$SOURCE")" && pwd)"
LIB="$ROOT/lib"
RUNTIME="$LIB/runtime"
APP="$RUNTIME/app"
PROJECT="$LIB/project"
READY="$RUNTIME/.producer-ready"
# Bump when the bootstrap recipe changes (python version, install steps...).
RUNTIME_VERSION="2"

usage() {
    cat <<'USAGE'
Producer - local speech cleanup and podcast mastering (VoiceForge).

Usage: ./producer.sh COMMAND [options]

  process RECORDING.wav...   Master one or more WAV files
  preview RECORDING.wav      Render loudness-matched profile previews
  analyze RECORDING.wav      Print measurements as JSON on stdout
  config                     Print resolved settings (TOML, or JSON with --json)
  doctor                     Check FFmpeg, data directory and CUDA driver
  setup --device cpu|cuda    Install and self-test the AI backend

Outputs are written beside each input by default. Run
'./producer.sh COMMAND --help' for the options of a command.
'./producer.sh --rebuild COMMAND...' re-runs the bootstrap first, for example
after changing the source code under lib/project. A rebuild waits for
running producer jobs to finish.
USAGE
}

log() { printf '[producer] %s\n' "$*" >&2; }
fail() { printf '[producer] Error: %s\n' "$*" >&2; exit 1; }

case "${1:-}" in
    -h|--help) usage; exit 0 ;;
esac

REBUILD=0
ARGS=()
for arg in "$@"; do
    case "$arg" in
        --rebuild) REBUILD=1 ;;
        *) ARGS+=("$arg") ;;
    esac
done
# 'producer.sh --rebuild --help' asks for help, not a rebuild.
if [[ ${#ARGS[@]} -eq 1 && ( "${ARGS[0]}" == "-h" || "${ARGS[0]}" == "--help" ) ]]; then
    usage
    exit 0
fi

mkdir -p -- "$RUNTIME/cache/pip" "$RUNTIME/cache/uv" "$RUNTIME/uv" "$RUNTIME/tmp" \
    || fail "Cannot create the runtime directory under $LIB"

# Contained environment: host Python settings and package-manager caches
# cannot leak in, and nothing (temporary files included) is written outside
# lib/runtime. Installation-target, index, and constraint overrides from the
# host are dropped and package-manager configuration files are disabled, so
# packages can only come from the explicitly passed trusted indexes and land
# inside lib/runtime. The application reads VOICEFORGE_HOME for AI envs and
# models.
unset PYTHONPATH PYTHONHOME VIRTUAL_ENV \
    PIP_TARGET PIP_PREFIX PIP_USER PIP_FIND_LINKS PIP_INDEX_URL PIP_EXTRA_INDEX_URL \
    PIP_CONSTRAINT \
    UV_INDEX_URL UV_DEFAULT_INDEX UV_EXTRA_INDEX_URL UV_INDEX UV_FIND_LINKS \
    UV_CONSTRAINT
export PYTHONNOUSERSITE=1
export PIP_CACHE_DIR="$RUNTIME/cache/pip" UV_CACHE_DIR="$RUNTIME/cache/uv"
export PIP_CONFIG_FILE=/dev/null UV_NO_CONFIG=1
export UV_PYTHON_INSTALL_DIR="$RUNTIME/uv/python" XDG_CACHE_HOME="$RUNTIME/cache"
export TMPDIR="$RUNTIME/tmp" VOICEFORGE_HOME="$RUNTIME"

marker_current() {
    # The marker must name this exact path, and the interpreter must exist:
    # a failed or interrupted rebuild leaves neither, forcing a repair.
    [[ -f "$READY" ]] \
        && [[ "$(cat -- "$READY" 2>/dev/null)" == "$RUNTIME v$RUNTIME_VERSION" ]] \
        && [[ -x "$APP/bin/python" ]]
}

bootstrap() {
    command -v flock >/dev/null 2>&1 \
        || fail "The 'flock' utility (util-linux) is required but was not found."
    # Bootstrap lock (fd 9): serializes bootstrap across launches and covers
    # the whole destructive window below. It is released before the
    # application starts.
    exec 9>"$RUNTIME/bootstrap.lock"
    flock 9
    if [[ "$REBUILD" -eq 0 ]] && marker_current; then
        exec 9>&-
        # Runtime lock (fd 8): held shared for the application's lifetime so
        # a later --rebuild cannot delete files this process runs from.
        exec 8>"$RUNTIME/app.lock"
        flock -s 8
        return 0
    fi
    # Exclusive runtime lock: waits out running jobs before anything is
    # deleted, so a rebuild can never clobber a live environment.
    exec 8>"$RUNTIME/app.lock"
    if ! flock -n 8; then
        log "Waiting for running producer jobs to finish before building the runtime"
        flock 8
    fi
    # Invalidate the marker before any destructive work: if this bootstrap
    # fails or is interrupted, the next launch repairs instead of trusting
    # a half-built environment.
    rm -f -- "$READY" "$READY.tmp"
    log "Preparing the contained runtime in lib/runtime (first run, or the directory moved)"

    local UV=""
    local err=""
    if [[ -x "$RUNTIME/bootstrap/bin/uv" ]] \
            && "$RUNTIME/bootstrap/bin/uv" --version >/dev/null 2>&1; then
        UV="$RUNTIME/bootstrap/bin/uv"
    elif command -v uv >/dev/null 2>&1; then
        UV="$(command -v uv)"
    else
        command -v python3 >/dev/null 2>&1 \
            || fail "First-run bootstrap needs 'uv' or Python 3 with venv support; neither was found."
        log "Bootstrapping uv from PyPI"
        rm -rf -- "$RUNTIME/bootstrap"
        python3 -m venv "$RUNTIME/bootstrap" \
            || fail "python3 -m venv failed; install venv support with your system package manager and retry. Nothing was run with sudo."
        "$RUNTIME/bootstrap/bin/python" -m pip install --index-url https://pypi.org/simple 'uv==0.8.17' >/dev/null \
            || fail "Downloading uv from PyPI failed; check network access."
        UV="$RUNTIME/bootstrap/bin/uv"
    fi

    # Managed-Python alias links are absolute; after a move they dangle while
    # the downloaded payload is still intact. Drop stale links so uv
    # re-resolves what is already on disk instead of re-downloading.
    find "$RUNTIME/uv" -maxdepth 1 -type l ! -exec test -e {} \; -delete 2>/dev/null || true

    rm -rf -- "$APP"
    # Python 3.13 for the application runtime: earlier musl builds from uv
    # misreport their extension suffix and cannot load musl-tagged wheels.
    # The AI worker keeps its own pinned Python 3.11 (glibc only).
    "$UV" venv --python 3.13 --managed-python --relocatable --allow-existing "$APP" \
        || fail "Creating the managed Python 3.13 environment failed; check network access and free space."
    # The bundled FFmpeg wheel is preferred; where it does not exist (for
    # example musl systems), fall back to a system FFmpeg at runtime.
    if ! err="$("$UV" pip install --python "$APP/bin/python" --index-url https://pypi.org/simple \
            "$PROJECT[bundled-ffmpeg]" 2>&1 >/dev/null)"; then
        log "Bundled FFmpeg wheel unavailable; installing core dependencies (a system FFmpeg is then required)."
        if [[ -n "$err" ]]; then
            sed 's/^/[producer]   /' <<<"$err" >&2
        fi
        "$UV" pip install --python "$APP/bin/python" --index-url https://pypi.org/simple "$PROJECT" \
            || fail "Installing the application dependencies failed; check network access and free space."
    fi
    "$APP/bin/python" -I -c "import voiceforge" >/dev/null 2>&1 \
        || fail "The application environment failed verification."

    printf '%s v%s\n' "$RUNTIME" "$RUNTIME_VERSION" > "$READY.tmp"
    mv -f -- "$READY.tmp" "$READY"
    # Downgrade to the shared runtime lock for the application's lifetime.
    flock -s 8
    exec 9>&-
}

bootstrap
exec "$APP/bin/python" -I -m voiceforge ${ARGS[@]+"${ARGS[@]}"}