#!/bin/sh
# Unsloth Studio Installer
# Usage (curl):  curl -fsSL https://unsloth.ai/install.sh | sh
# Usage (wget):  wget -qO- https://unsloth.ai/install.sh | sh
# Usage (local): ./install.sh --local   (install from local repo instead of PyPI)
# Usage (no-torch): ./install.sh --no-torch  (skip PyTorch, GGUF-only mode)
# Usage (test):  ./install.sh --package roland-sloth  (install a different package name)
# Usage (py):    ./install.sh --python 3.12  (override auto-detected Python version)
set -e

# ── Output style (aligned with studio/setup.sh) ──
RULE=""
_rule_i=0
while [ "$_rule_i" -lt 52 ]; do
    RULE="${RULE}─"
    _rule_i=$((_rule_i + 1))
done
if [ -n "${NO_COLOR:-}" ]; then
    C_TITLE= C_DIM= C_OK= C_WARN= C_ERR= C_RST=
elif [ -t 1 ] || [ -n "${FORCE_COLOR:-}" ]; then
    _ESC="$(printf '\033')"
    C_TITLE="${_ESC}[38;5;150m"
    C_DIM="${_ESC}[38;5;245m"
    C_OK="${_ESC}[38;5;108m"
    C_WARN="${_ESC}[38;5;136m"
    C_ERR="${_ESC}[91m"
    C_RST="${_ESC}[0m"
else
    C_TITLE= C_DIM= C_OK= C_WARN= C_ERR= C_RST=
fi

step()    { printf "  ${C_DIM}%-15.15s${C_RST}${3:-$C_OK}%s${C_RST}\n" "$1" "$2"; }
substep() { printf "  ${C_DIM}%-15s${2:-$C_DIM}%s${C_RST}\n" "" "$1"; }

# ── Parse flags ──
STUDIO_LOCAL_INSTALL=false
PACKAGE_NAME="unsloth"
_USER_PYTHON=""
_NO_TORCH_FLAG=false
_VERBOSE=false
_next_is_package=false
_next_is_python=false
for arg in "$@"; do
    if [ "$_next_is_package" = true ]; then
        PACKAGE_NAME="$arg"
        _next_is_package=false
        continue
    fi
    if [ "$_next_is_python" = true ]; then
        _USER_PYTHON="$arg"
        _next_is_python=false
        continue
    fi
    case "$arg" in
        --local) STUDIO_LOCAL_INSTALL=true ;;
        --package) _next_is_package=true ;;
        --python) _next_is_python=true ;;
        --no-torch) _NO_TORCH_FLAG=true ;;
        --verbose|-v) _VERBOSE=true ;;
    esac
done

if [ "$_VERBOSE" = true ]; then
    export UNSLOTH_VERBOSE=1
fi

_is_verbose() {
    [ "${UNSLOTH_VERBOSE:-0}" = "1" ]
}

run_maybe_quiet() {
    if _is_verbose; then
        "$@"
    else
        "$@" > /dev/null 2>&1
    fi
}

run_install_cmd() {
    _label="$1"
    shift
    if _is_verbose; then
        "$@" && return 0
        _rc=$?
        step "error" "$_label failed (exit code $_rc)" "$C_ERR" >&2
        return "$_rc"
    fi
    _log=$(mktemp)
    "$@" >"$_log" 2>&1 && { rm -f "$_log"; return 0; }
    _rc=$?
    step "error" "$_label failed (exit code $_rc)" "$C_ERR" >&2
    cat "$_log" >&2
    rm -f "$_log"
    return $_rc
}

# Install bitsandbytes on AMD ROCm hosts. Uses the continuous-release_main
# wheel for the ROCm 4-bit GEMV fix (bnb PR #1887, post-0.49.2); bnb <= 0.49.2
# NaNs at decode shape on every AMD GPU. Falls back to PyPI >=0.49.1 if the
# pre-release URL is unreachable. Drop the pin once bnb 0.50+ ships on PyPI.
_install_bnb_rocm() {
    _label="$1"
    _venv_py="$2"
    case "$_ARCH" in
        x86_64|amd64)
            _bnb_whl_url="https://github.com/bitsandbytes-foundation/bitsandbytes/releases/download/continuous-release_main/bitsandbytes-1.33.7.preview-py3-none-manylinux_2_24_x86_64.whl"
            ;;
        aarch64|arm64)
            _bnb_whl_url="https://github.com/bitsandbytes-foundation/bitsandbytes/releases/download/continuous-release_main/bitsandbytes-1.33.7.preview-py3-none-manylinux_2_24_aarch64.whl"
            ;;
        *)
            _bnb_whl_url=""
            ;;
    esac
    # uv rejects the continuous-release_main bitsandbytes wheel because the
    # filename version (1.33.7rc0) does not match the embedded metadata version
    # (0.50.0.dev0). pip accepts the mismatch, so bootstrap pip and use it.
    if ! "$_venv_py" -m pip --version >/dev/null 2>&1; then
        if ! run_maybe_quiet "$_venv_py" -m ensurepip --upgrade; then
            run_maybe_quiet uv pip install --python "$_venv_py" pip || \
                substep "[WARN] could not bootstrap pip; bitsandbytes install will likely fail" "$C_WARN"
        fi
    fi
    if [ -n "$_bnb_whl_url" ]; then
        substep "installing bitsandbytes for AMD ROCm (pre-release, PR #1887)..."
        if run_install_cmd "$_label (pre-release)" "$_venv_py" -m pip install \
            --force-reinstall --no-cache-dir --no-deps "$_bnb_whl_url"; then
            return 0
        fi
        substep "[WARN] bnb pre-release install failed; falling back to PyPI (4-bit decode broken on ROCm)" "$C_WARN"
    fi
    run_install_cmd "$_label (pypi fallback)" "$_venv_py" -m pip install \
        --force-reinstall --no-cache-dir --no-deps "bitsandbytes>=0.49.1"
}

if [ "$_next_is_package" = true ]; then
    echo "❌ ERROR: --package requires an argument." >&2
    exit 1
fi
if [ "$_next_is_python" = true ]; then
    echo "❌ ERROR: --python requires a version argument (e.g. --python 3.12)." >&2
    exit 1
fi

PYTHON_VERSION=""  # resolved after platform detection
STUDIO_HOME="$HOME/.unsloth/studio"
VENV_DIR="$STUDIO_HOME/unsloth_studio"

# ── Helper: download a URL to a file (supports curl and wget) ──
download() {
    if command -v curl >/dev/null 2>&1; then
        curl -LsSf "$1" -o "$2"
    elif command -v wget >/dev/null 2>&1; then
        wget -qO "$2" "$1"
    else
        echo "Error: neither curl nor wget found. Install one and re-run."
        exit 1
    fi
}

# ── Helper: check if a single package is available on the system ──
_is_pkg_installed() {
    case "$1" in
        build-essential) command -v gcc >/dev/null 2>&1 ;;
        libcurl4-openssl-dev)
            command -v dpkg >/dev/null 2>&1 && dpkg -s "$1" >/dev/null 2>&1 ;;
        pciutils)
            command -v lspci >/dev/null 2>&1 ;;
        *) command -v "$1" >/dev/null 2>&1 ;;
    esac
}

# ── Helper: install packages via apt, escalating to sudo only if needed ──
# Usage: _smart_apt_install pkg1 pkg2 pkg3 ...
_smart_apt_install() {
    _PKGS="$*"

    # Step 1: Try installing without sudo (works when already root)
    apt-get update -y </dev/null >/dev/null 2>&1 || true
    apt-get install -y $_PKGS </dev/null >/dev/null 2>&1 || true

    # Step 2: Check which packages are still missing
    _STILL_MISSING=""
    for _pkg in $_PKGS; do
        if ! _is_pkg_installed "$_pkg"; then
            _STILL_MISSING="$_STILL_MISSING $_pkg"
        fi
    done
    _STILL_MISSING=$(echo "$_STILL_MISSING" | sed 's/^ *//')

    if [ -z "$_STILL_MISSING" ]; then
        return 0
    fi

    # Step 3: Escalate -- need elevated permissions for remaining packages
    if command -v sudo >/dev/null 2>&1; then
        echo ""
        echo "    !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!"
        echo "    WARNING: We require sudo elevated permissions to install:"
        echo "    $_STILL_MISSING"
        echo "    If you accept, we'll run sudo now, and it'll prompt your password."
        echo "    !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!"
        echo ""
        printf "    Accept? [Y/n] "
        if [ -r /dev/tty ]; then
            read -r REPLY </dev/tty || REPLY="y"
        else
            REPLY="y"
        fi
        case "$REPLY" in
            [nN]*)
                echo ""
                echo "    Please install these packages first, then re-run Unsloth Studio setup:"
                echo "    sudo apt-get update -y && sudo apt-get install -y $_STILL_MISSING"
                exit 1
                ;;
            *)
                sudo apt-get update -y </dev/null
                sudo apt-get install -y $_STILL_MISSING </dev/null
                ;;
        esac
    else
        echo ""
        echo "    sudo is not available on this system."
        echo "    Please install these packages as root, then re-run Unsloth Studio setup:"
        echo "    apt-get update -y && apt-get install -y $_STILL_MISSING"
        exit 1
    fi
}

# ── Helper: create desktop shortcuts and launcher script ──
# Usage: create_studio_shortcuts <unsloth_exe> <os>
# Creates ~/.local/share/unsloth/launch-studio.sh (shared launcher),
# plus platform-specific shortcuts (Linux .desktop / macOS .app bundle /
# WSL Windows Desktop+Start Menu .lnk).
create_studio_shortcuts() {
    _css_exe="$1"
    _css_os="$2"

    # Validate exe
    if [ ! -x "$_css_exe" ]; then
        echo "[WARN] Cannot create shortcuts: unsloth not found at $_css_exe"
        return 0
    fi

    # Resolve absolute path
    _css_exe_dir=$(cd "$(dirname "$_css_exe")" && pwd)
    _css_exe="$_css_exe_dir/$(basename "$_css_exe")"

    _css_data_dir="$HOME/.local/share/unsloth"
    _css_launcher="$_css_data_dir/launch-studio.sh"
    _css_icon_png="$_css_data_dir/unsloth-studio.png"
    _css_gem_png="$_css_data_dir/unsloth-gem.png"

    mkdir -p "$_css_data_dir"

    # ── Write launcher script ──
    # The launcher is Bash (not POSIX sh).
    # We write it with a placeholder and substitute the exe path via sed.
    cat > "$_css_launcher" << 'LAUNCHER_EOF'
#!/usr/bin/env bash
# Unsloth Studio Launcher
# Auto-generated by install.sh -- do not edit manually.
set -euo pipefail

DATA_DIR="$HOME/.local/share/unsloth"

# Read exe path from config written at install time.
# Sourcing is safe: the config file is written by install.sh, not user input.
if [ -f "$DATA_DIR/studio.conf" ]; then
    . "$DATA_DIR/studio.conf"
fi
if [ -z "${UNSLOTH_EXE:-}" ] || [ ! -x "${UNSLOTH_EXE:-}" ]; then
    echo "Error: UNSLOTH_EXE not set or not executable. Re-run the installer." >&2
    exit 1
fi

BASE_PORT=8888
MAX_PORT_OFFSET=20
TIMEOUT_SEC=60
POLL_INTERVAL_SEC=1
LOG_FILE="$DATA_DIR/studio.log"
LOCK_DIR="${XDG_RUNTIME_DIR:-/tmp}/unsloth-studio-launcher-$(id -u).lock"

# ── HTTP GET helper (supports curl and wget) ──
_http_get() {
    _url="$1"
    if command -v curl >/dev/null 2>&1; then
        curl -fsS --max-time 1 "$_url" 2>/dev/null
    elif command -v wget >/dev/null 2>&1; then
        wget -qO- --timeout=1 "$_url" 2>/dev/null
    else
        return 1
    fi
}

# ── Health check ──
_check_health() {
    _port=$1
    _resp=$(_http_get "http://127.0.0.1:$_port/api/health") || return 1
    case "$_resp" in
        *'"status"'*'"healthy"'*'"service"'*'"Unsloth UI Backend"'*) return 0 ;;
        *'"service"'*'"Unsloth UI Backend"'*'"status"'*'"healthy"'*) return 0 ;;
    esac
    return 1
}

# ── Port scanning ──
_candidate_ports() {
    echo "$BASE_PORT"
    _max_port=$((BASE_PORT + MAX_PORT_OFFSET))
    if command -v ss >/dev/null 2>&1; then
        ss -tlnH 2>/dev/null | awk '{print $4}' | grep -oE '[0-9]+$' | \
            awk -v lo="$BASE_PORT" -v hi="$_max_port" '$1 >= lo && $1 <= hi && $1 != lo {print}' || true
    elif command -v lsof >/dev/null 2>&1; then
        lsof -iTCP -sTCP:LISTEN -nP 2>/dev/null | awk '{print $9}' | grep -oE '[0-9]+$' | \
            awk -v lo="$BASE_PORT" -v hi="$_max_port" '$1 >= lo && $1 <= hi && $1 != lo {print}' || true
    else
        _offset=1
        while [ "$_offset" -le "$MAX_PORT_OFFSET" ]; do
            echo $((BASE_PORT + _offset))
            _offset=$((_offset + 1))
        done
    fi
}

_find_healthy_port() {
    for _p in $(_candidate_ports | sort -un); do
        if _check_health "$_p"; then
            echo "$_p"
            return 0
        fi
    done
    return 1
}

# ── Check if a port is busy ──
_is_port_busy() {
    _port=$1
    if command -v ss >/dev/null 2>&1; then
        ss -tlnH 2>/dev/null | awk '{print $4}' | grep -qE "[.:]$_port$"
    elif command -v lsof >/dev/null 2>&1; then
        lsof -iTCP:"$_port" -sTCP:LISTEN -nP >/dev/null 2>&1
    else
        return 1
    fi
}

# ── Find a free port in range ──
_find_launch_port() {
    _offset=0
    while [ "$_offset" -le "$MAX_PORT_OFFSET" ]; do
        _candidate=$((BASE_PORT + _offset))
        if ! _is_port_busy "$_candidate"; then
            echo "$_candidate"
            return 0
        fi
        _offset=$((_offset + 1))
    done
    return 1
}

# ── Open browser ──
_open_browser() {
    _url="$1"
    if [ "$(uname)" = "Darwin" ] && command -v open >/dev/null 2>&1; then
        open "$_url"
    elif grep -qi microsoft /proc/version 2>/dev/null; then
        # WSL: xdg-open is unreliable; use Windows browser via PowerShell or cmd
        if command -v powershell.exe >/dev/null 2>&1; then
            powershell.exe -NoProfile -Command "Start-Process '$_url'" >/dev/null 2>&1 &
        elif command -v cmd.exe >/dev/null 2>&1; then
            cmd.exe /c start "" "$_url" >/dev/null 2>&1 &
        elif command -v xdg-open >/dev/null 2>&1; then
            xdg-open "$_url" >/dev/null 2>&1 &
        else
            echo "Open in your browser: $_url" >&2
        fi
    elif command -v xdg-open >/dev/null 2>&1; then
        xdg-open "$_url" >/dev/null 2>&1 &
    else
        echo "Open in your browser: $_url" >&2
    fi
}

# ── Spawn terminal with studio command ──
_spawn_terminal() {
    _cmd="$1"
    _os=$(uname)
    if [ "$_os" = "Darwin" ]; then
        # Escape backslashes and double-quotes for AppleScript string
        _cmd_escaped=$(printf '%s' "$_cmd" | sed 's/\\/\\\\/g; s/"/\\"/g')
        osascript -e "tell application \"Terminal\" to do script \"$_cmd_escaped\"" >/dev/null 2>&1 && return 0
    else
        for _term in gnome-terminal konsole xfce4-terminal mate-terminal lxterminal xterm; do
            if command -v "$_term" >/dev/null 2>&1; then
                case "$_term" in
                    gnome-terminal) "$_term" -- sh -c "$_cmd" & return 0 ;;
                    konsole)        "$_term" -e sh -c "$_cmd" & return 0 ;;
                    xterm)          "$_term" -e sh -c "$_cmd" & return 0 ;;
                    *)              "$_term" -e sh -c "$_cmd" & return 0 ;;
                esac
            fi
        done
    fi
    # Fallback: background with log
    echo "No terminal emulator found; running in background. Logs: $LOG_FILE" >&2
    nohup sh -c "$_cmd" >> "$LOG_FILE" 2>&1 &
    return 0
}

# ── Atomic directory-based single-instance guard ──
_acquire_lock() {
    if mkdir "$LOCK_DIR" 2>/dev/null; then
        echo "$$" > "$LOCK_DIR/pid"
        return 0
    fi

    # Lock dir exists -- check if owner is still alive
    _old_pid=$(cat "$LOCK_DIR/pid" 2>/dev/null || true)
    if [ -n "$_old_pid" ] && kill -0 "$_old_pid" 2>/dev/null; then
        # Another launcher is running; wait for it to bring Studio up
        _deadline=$(($(date +%s) + TIMEOUT_SEC))
        while [ "$(date +%s)" -lt "$_deadline" ]; do
            _port=$(_find_healthy_port) && {
                _open_browser "http://localhost:$_port"
                exit 0
            }
            sleep "$POLL_INTERVAL_SEC"
        done
        echo "Timed out waiting for other launcher (PID $_old_pid)" >&2
        exit 0
    fi

    # Stale lock -- reclaim
    rm -rf "$LOCK_DIR"
    mkdir "$LOCK_DIR" 2>/dev/null || return 1
    echo "$$" > "$LOCK_DIR/pid"
}

_release_lock() {
    [ -d "$LOCK_DIR" ] || return 0
    [ "$(cat "$LOCK_DIR/pid" 2>/dev/null)" = "$$" ] || return 0
    rm -rf "$LOCK_DIR"
}

# ── Main ──
# Fast path: already healthy
_port=$(_find_healthy_port) && {
    _open_browser "http://localhost:$_port"
    exit 0
}

_acquire_lock
trap '_release_lock' EXIT INT TERM

# Post-lock re-check (handles race with another launcher)
_port=$(_find_healthy_port) && {
    _open_browser "http://localhost:$_port"
    exit 0
}

# Find a free port in range
_launch_port=$(_find_launch_port) || {
    echo "No free port found in range ${BASE_PORT}-$((BASE_PORT + MAX_PORT_OFFSET))" >&2
    exit 1
}

if [ -t 1 ]; then
    # ── Foreground mode (TTY available) ──
    # Background subshell: wait for studio to become healthy, release the
    # single-instance lock, then open the browser. The lock stays held until
    # health is confirmed so a second launcher cannot race during startup.
    (
        _obwr_deadline=$(($(date +%s) + TIMEOUT_SEC))
        while [ "$(date +%s)" -lt "$_obwr_deadline" ]; do
            if _check_health "$_launch_port"; then
                _release_lock
                _open_browser "http://localhost:$_launch_port"
                exit 0
            fi
            sleep "$POLL_INTERVAL_SEC"
        done
        # Timed out -- release the lock anyway so future launches are not blocked
        _release_lock
    ) &
    # Clear traps so exec does not trigger _release_lock (the subshell owns it)
    trap - EXIT INT TERM
    exec "$UNSLOTH_EXE" studio -H 0.0.0.0 -p "$_launch_port"
else
    # ── Background mode (no TTY) ──
    # Used by macOS .app and headless invocations.
    _launch_cmd=$(printf '%q ' "$UNSLOTH_EXE" studio -H 0.0.0.0 -p "$_launch_port")
    _launch_cmd=${_launch_cmd% }
    _spawn_terminal "$_launch_cmd"

    # Poll for health on the specific port we launched on
    _deadline=$(($(date +%s) + TIMEOUT_SEC))
    while [ "$(date +%s)" -lt "$_deadline" ]; do
        if _check_health "$_launch_port"; then
            _open_browser "http://localhost:$_launch_port"
            exit 0
        fi
        sleep "$POLL_INTERVAL_SEC"
    done

    echo "Unsloth Studio did not become healthy within ${TIMEOUT_SEC}s." >&2
    echo "Check logs at: $LOG_FILE" >&2
    exit 1
fi
LAUNCHER_EOF

    chmod +x "$_css_launcher"

    # Write the exe path to a separate conf file sourced by the launcher.
    # Using single-quote wrapping with the standard '\'' escape for any
    # embedded apostrophes. This avoids all sed metacharacter issues.
    _css_quoted_exe=$(printf '%s' "$_css_exe" | sed "s/'/'\\\\''/g")
    printf '%s\n' "UNSLOTH_EXE='$_css_quoted_exe'" > "$_css_data_dir/studio.conf"

    # ── Icon: try bundled, then download ──
    # rounded-512.png used for both Linux and macOS icons
    _css_script_dir=""
    if [ -n "${0:-}" ] && [ -f "$0" ]; then
        _css_script_dir=$(cd "$(dirname "$0")" 2>/dev/null && pwd) || true
    fi

    # Try to find rounded-512.png from installed package (site-packages) or local repo
    _css_found_icon=""
    _css_venv_dir=$(dirname "$(dirname "$_css_exe")")
    # Check site-packages
    for _sp in "$_css_venv_dir"/lib/python*/site-packages/unsloth/studio/frontend/public; do
        if [ -f "$_sp/rounded-512.png" ]; then
            _css_found_icon="$_sp/rounded-512.png"
        fi
    done
    # Check local repo (when running from clone)
    if [ -z "$_css_found_icon" ] && [ -n "$_css_script_dir" ] && [ -f "$_css_script_dir/studio/frontend/public/rounded-512.png" ]; then
        _css_found_icon="$_css_script_dir/studio/frontend/public/rounded-512.png"
    fi

    # Copy or download rounded-512.png (used for both Linux icon and macOS icns)
    if [ -n "$_css_found_icon" ]; then
        cp "$_css_found_icon" "$_css_icon_png" 2>/dev/null || true
        cp "$_css_found_icon" "$_css_gem_png" 2>/dev/null || true
    else
        download "https://raw.githubusercontent.com/unslothai/unsloth/main/studio/frontend/public/rounded-512.png" "$_css_icon_png" 2>/dev/null || true
        cp "$_css_icon_png" "$_css_gem_png" 2>/dev/null || true
    fi

    # Validate PNG header (first 4 bytes: \x89PNG)
    _css_validate_png() {
        [ -f "$1" ] || return 1
        _hdr=$(od -An -tx1 -N4 "$1" 2>/dev/null | tr -d ' ')
        [ "$_hdr" = "89504e47" ]
    }
    if [ -f "$_css_icon_png" ] && ! _css_validate_png "$_css_icon_png"; then
        rm -f "$_css_icon_png"
    fi
    if [ -f "$_css_gem_png" ] && ! _css_validate_png "$_css_gem_png"; then
        rm -f "$_css_gem_png"
    fi

    # ── Platform-specific shortcuts ──
    _css_created=0

    if [ "$_css_os" = "linux" ]; then
        # ── Linux: .desktop file ──
        _css_app_dir="$HOME/.local/share/applications"
        mkdir -p "$_css_app_dir"

        _css_desktop="$_css_app_dir/unsloth-studio.desktop"
        # Escape backslashes and double-quotes for .desktop Exec= field
        _css_exec_escaped=$(printf '%s' "$_css_launcher" | sed 's/\\/\\\\/g; s/"/\\"/g')
        _css_icon_escaped=$(printf '%s' "$_css_icon_png" | sed 's/\\/\\\\/g; s/"/\\"/g')
        cat > "$_css_desktop" << DESKTOP_EOF
[Desktop Entry]
Version=1.0
Type=Application
Name=Unsloth Studio
Comment=Launch Unsloth Studio
Exec="$_css_exec_escaped"
Icon=$_css_icon_escaped
Terminal=true
StartupNotify=true
Categories=Development;Science;
DESKTOP_EOF
        chmod +x "$_css_desktop"

        # Copy to ~/Desktop if it exists
        if [ -d "$HOME/Desktop" ]; then
            cp "$_css_desktop" "$HOME/Desktop/unsloth-studio.desktop" 2>/dev/null || true
            chmod +x "$HOME/Desktop/unsloth-studio.desktop" 2>/dev/null || true
            # Mark as trusted so GNOME/Nautilus allows launching via double-click
            if command -v gio >/dev/null 2>&1; then
                gio set "$HOME/Desktop/unsloth-studio.desktop" metadata::trusted true 2>/dev/null || true
            fi
        fi

        # Best-effort update database
        update-desktop-database "$_css_app_dir" 2>/dev/null || true
        _css_created=1

    elif [ "$_css_os" = "macos" ]; then
        # ── macOS: .app bundle ──
        _css_app="$HOME/Applications/Unsloth Studio.app"
        _css_contents="$_css_app/Contents"
        _css_macos_dir="$_css_contents/MacOS"
        _css_res_dir="$_css_contents/Resources"
        mkdir -p "$_css_macos_dir" "$_css_res_dir"

        # Info.plist
        cat > "$_css_contents/Info.plist" << 'PLIST_EOF'
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
    <key>CFBundleIdentifier</key>
    <string>ai.unsloth.studio</string>
    <key>CFBundleName</key>
    <string>Unsloth Studio</string>
    <key>CFBundleDisplayName</key>
    <string>Unsloth Studio</string>
    <key>CFBundleExecutable</key>
    <string>launch-studio</string>
    <key>CFBundleIconFile</key>
    <string>AppIcon</string>
    <key>CFBundlePackageType</key>
    <string>APPL</string>
    <key>CFBundleVersion</key>
    <string>1.0</string>
    <key>CFBundleShortVersionString</key>
    <string>1.0</string>
    <key>LSMinimumSystemVersion</key>
    <string>10.15</string>
    <key>NSHighResolutionCapable</key>
    <true/>
</dict>
</plist>
PLIST_EOF

        # Executable stub
        cat > "$_css_macos_dir/launch-studio" << STUB_EOF
#!/bin/sh
exec "$HOME/.local/share/unsloth/launch-studio.sh" "\$@"
STUB_EOF
        chmod +x "$_css_macos_dir/launch-studio"

        # Build AppIcon.icns from unsloth-gem.png (2240x2240)
        if [ -f "$_css_gem_png" ] && command -v sips >/dev/null 2>&1 && command -v iconutil >/dev/null 2>&1; then
            _css_tmpdir=$(mktemp -d 2>/dev/null)
            if [ -d "$_css_tmpdir" ]; then
                _css_iconset="$_css_tmpdir/AppIcon.iconset"
                mkdir -p "$_css_iconset"
                _css_icon_ok=true
                for _sz in 16 32 128 256 512; do
                    _sz2=$((_sz * 2))
                    sips -z "$_sz" "$_sz" "$_css_gem_png" --out "$_css_iconset/icon_${_sz}x${_sz}.png" >/dev/null 2>&1 || _css_icon_ok=false
                    sips -z "$_sz2" "$_sz2" "$_css_gem_png" --out "$_css_iconset/icon_${_sz}x${_sz}@2x.png" >/dev/null 2>&1 || _css_icon_ok=false
                done
                if [ "$_css_icon_ok" = "true" ]; then
                    iconutil -c icns "$_css_iconset" -o "$_css_res_dir/AppIcon.icns" 2>/dev/null || true
                fi
                rm -rf "$_css_tmpdir"
            fi
        fi
        # Fallback: copy PNG as icon
        if [ ! -f "$_css_res_dir/AppIcon.icns" ] && [ -f "$_css_icon_png" ]; then
            cp "$_css_icon_png" "$_css_res_dir/AppIcon.icns" 2>/dev/null || true
        fi

        # Touch so Finder indexes it
        touch "$_css_app"

        # Symlink on Desktop
        if [ -d "$HOME/Desktop" ]; then
            ln -sf "$_css_app" "$HOME/Desktop/Unsloth Studio" 2>/dev/null || true
        fi
        _css_created=1

    elif [ "$_css_os" = "wsl" ]; then
        # ── WSL: create Windows Desktop and Start Menu shortcuts ──
        # Detect current WSL distro for targeted shortcut
        _css_distro="${WSL_DISTRO_NAME:-}"

        # Build the wsl.exe arguments.
        # Double-quote distro name and launcher path for Windows command line
        # parsing so values with spaces (e.g. "Ubuntu Preview") are kept as
        # single arguments.
        _css_wsl_args=""
        if [ -n "$_css_distro" ]; then
            _css_wsl_args="-d \"$_css_distro\" "
        fi
        _css_wsl_args="${_css_wsl_args}-- bash -l -c \"exec \\\"$_css_launcher\\\"\""

        # Detect whether Windows Terminal (wt.exe) is available (better UX)
        _css_use_wt=false
        if command -v wt.exe >/dev/null 2>&1; then
            _css_use_wt=true
        fi

        if [ "$_css_use_wt" = true ]; then
            _css_sc_target='wt.exe'
            _css_sc_args="wsl.exe $_css_wsl_args"
        else
            _css_sc_target='wsl.exe'
            _css_sc_args="$_css_wsl_args"
        fi

        # Escape single quotes for PowerShell single-quoted string embedding
        _css_sc_args_ps=$(printf '%s' "$_css_sc_args" | sed "s/'/''/g")

        # Create shortcuts via a temp PowerShell script to avoid escaping issues
        _css_ps1_tmp=$(mktemp /tmp/unsloth-shortcut-XXXXXX.ps1 2>/dev/null) || true
        if [ -n "$_css_ps1_tmp" ]; then
            cat > "$_css_ps1_tmp" << WSLPS1_EOF
\$WshShell = New-Object -ComObject WScript.Shell
\$targetExe = (Get-Command '$_css_sc_target' -ErrorAction SilentlyContinue).Source
if (-not \$targetExe) { exit 1 }
\$locations = @(
    [Environment]::GetFolderPath('Desktop'),
    (Join-Path \$env:APPDATA 'Microsoft\Windows\Start Menu\Programs')
)
foreach (\$dir in \$locations) {
    if (-not \$dir -or -not (Test-Path \$dir)) { continue }
    \$linkPath = Join-Path \$dir 'Unsloth Studio.lnk'
    \$shortcut = \$WshShell.CreateShortcut(\$linkPath)
    \$shortcut.TargetPath = \$targetExe
    \$shortcut.Arguments = '$_css_sc_args_ps'
    \$shortcut.Description = 'Launch Unsloth Studio'
    \$shortcut.Save()
}
WSLPS1_EOF

            # Convert WSL path to Windows path for powershell.exe
            _css_ps1_win=$(wslpath -w "$_css_ps1_tmp" 2>/dev/null)
            if [ -n "$_css_ps1_win" ]; then
                powershell.exe -NoProfile -ExecutionPolicy Bypass -File "$_css_ps1_win" >/dev/null 2>&1 && _css_created=1
            fi
            rm -f "$_css_ps1_tmp"
        fi
    fi

    if [ "$_css_created" -eq 1 ]; then
        substep "Created Unsloth Studio shortcut"
    fi
}

echo ""
printf "  ${C_TITLE}%s${C_RST}\n" "🦥 Unsloth Studio Installer"
printf "  ${C_DIM}%s${C_RST}\n" "$RULE"
echo ""

# ── Detect platform ──
OS="linux"
if [ "$(uname)" = "Darwin" ]; then
    OS="macos"
elif grep -qi microsoft /proc/version 2>/dev/null; then
    OS="wsl"
fi
step "platform" "$OS"

# ── Architecture detection & Python version ──
_ARCH=$(uname -m)
MAC_INTEL=false
if [ "$OS" = "macos" ] && [ "$_ARCH" = "x86_64" ]; then
    # Guard against Apple Silicon running under Rosetta (reports x86_64).
    # sysctl hw.optional.arm64 returns "1" on Apple Silicon even in Rosetta.
    if [ "$(sysctl -in hw.optional.arm64 2>/dev/null || echo 0)" = "1" ]; then
        echo ""
        echo "  WARNING: Apple Silicon detected, but this shell is running under Rosetta (x86_64)."
        echo "  Re-run install.sh from a native arm64 terminal for full PyTorch support."
        echo "  Continuing in GGUF-only mode for now."
        echo ""
    fi
    MAC_INTEL=true
fi

if [ -n "$_USER_PYTHON" ]; then
    PYTHON_VERSION="$_USER_PYTHON"
    echo "  Using user-specified Python $PYTHON_VERSION (--python override)"
elif [ "$MAC_INTEL" = true ]; then
    PYTHON_VERSION="3.12"
else
    PYTHON_VERSION="3.13"
fi

if [ "$MAC_INTEL" = true ]; then
    echo ""
    echo "  NOTE: Intel Mac (x86_64) detected."
    echo "  PyTorch is unavailable for this platform (dropped Jan 2024)."
    echo "  Studio will install in GGUF-only mode."
    echo "  Chat, inference via GGUF, and data recipes will work."
    echo "  Training requires Apple Silicon or Linux with GPU."
    echo ""
fi

# ── Unified SKIP_TORCH: --no-torch flag OR Intel Mac auto-detection ──
SKIP_TORCH=false
if [ "$_NO_TORCH_FLAG" = true ] || [ "$MAC_INTEL" = true ]; then
    SKIP_TORCH=true
fi

# ── Check system dependencies ──
# cmake and git are needed by unsloth studio setup to build the GGUF inference
# engine (llama.cpp). build-essential and libcurl-dev are also needed on Linux.
MISSING=""

command -v cmake >/dev/null 2>&1 || MISSING="$MISSING cmake"
command -v git   >/dev/null 2>&1 || MISSING="$MISSING git"

case "$OS" in
    macos)
        # Xcode Command Line Tools provide the C/C++ compiler
        if ! xcode-select -p >/dev/null 2>&1; then
            echo ""
            echo "==> Xcode Command Line Tools are required."
            echo "    Installing (a system dialog will appear)..."
            xcode-select --install </dev/null 2>/dev/null || true
            echo "    After the installation completes, please re-run this script."
            exit 1
        fi
        ;;
    linux|wsl)
        # curl or wget is needed for downloads; check both
        if ! command -v curl >/dev/null 2>&1 && ! command -v wget >/dev/null 2>&1; then
            MISSING="$MISSING curl"
        fi
        command -v gcc  >/dev/null 2>&1 || MISSING="$MISSING build-essential"
        # libcurl dev headers for llama.cpp HTTPS support
        if command -v dpkg >/dev/null 2>&1; then
            dpkg -s libcurl4-openssl-dev >/dev/null 2>&1 || MISSING="$MISSING libcurl4-openssl-dev"
        fi
        ;;
esac

MISSING=$(echo "$MISSING" | sed 's/^ *//')

if [ -n "$MISSING" ]; then
    echo ""
    step "deps" "missing: $MISSING" "$C_WARN"
    substep "These are needed to build the GGUF inference engine."

    case "$OS" in
        macos)
            if ! command -v brew >/dev/null 2>&1; then
                echo ""
                echo "    Homebrew is required to install them."
                echo "    Install Homebrew from https://brew.sh then re-run this script."
                exit 1
            fi
            brew install $MISSING </dev/null
            ;;
        linux|wsl)
            if command -v apt-get >/dev/null 2>&1; then
                _smart_apt_install $MISSING
            else
                echo "    apt-get is not available. Please install with your package manager:"
                echo "    $MISSING"
                echo "    Then re-run Unsloth Studio setup."
                exit 1
            fi
            ;;
    esac
    echo ""
else
    step "deps" "all system dependencies found"
fi

# ── Install uv ──
UV_MIN_VERSION="0.7.14"

version_ge() {
    # returns 0 if $1 >= $2
    _a=$1
    _b=$2

    while [ -n "$_a" ] || [ -n "$_b" ]; do
        _a_part=${_a%%.*}
        _b_part=${_b%%.*}

        [ "$_a" = "$_a_part" ] && _a="" || _a=${_a#*.}
        [ "$_b" = "$_b_part" ] && _b="" || _b=${_b#*.}

        [ -z "$_a_part" ] && _a_part=0
        [ -z "$_b_part" ] && _b_part=0

        if [ "$_a_part" -gt "$_b_part" ]; then
            return 0
        fi
        if [ "$_a_part" -lt "$_b_part" ]; then
            return 1
        fi
    done

    return 0
}

_uv_version_ok() {
    _raw=$("$1" --version 2>/dev/null | awk '{print $2}') || return 1
    [ -n "$_raw" ] || return 1
    _ver=${_raw%%[-+]*}
    case "$_ver" in
        ''|*[!0-9.]*) return 1 ;;
    esac
    version_ge "$_ver" "$UV_MIN_VERSION" || return 1
    # Prerelease of the exact minimum (e.g. 0.7.14-rc1) is still below stable 0.7.14
    [ "$_ver" = "$UV_MIN_VERSION" ] && [ "$_raw" != "$_ver" ] && return 1
    return 0
}

if ! command -v uv >/dev/null 2>&1 || ! _uv_version_ok uv; then
    substep "installing uv package manager..."
    _uv_tmp=$(mktemp)
    download "https://astral.sh/uv/install.sh" "$_uv_tmp"
    run_maybe_quiet sh "$_uv_tmp" </dev/null
    rm -f "$_uv_tmp"
    if [ -f "$HOME/.local/bin/env" ]; then
        . "$HOME/.local/bin/env"
    fi
    export PATH="$HOME/.local/bin:$PATH"
fi

# ── Create venv (migrate old layout if possible, otherwise fresh) ──
mkdir -p "$STUDIO_HOME"

_MIGRATED=false

if [ -x "$VENV_DIR/bin/python" ]; then
    # New layout already exists — nuke for fresh install
    rm -rf "$VENV_DIR"
elif [ -x "$STUDIO_HOME/.venv/bin/python" ]; then
    # Old layout exists — validate before migrating
    substep "found legacy Studio environment, validating..."
    if "$STUDIO_HOME/.venv/bin/python" -c "
import torch
device = 'cuda' if torch.cuda.is_available() else 'cpu'
A = torch.ones((10, 10), device=device)
B = torch.ones((10, 10), device=device)
C = torch.ones((10, 10), device=device)
D = A + B
E = D @ C
torch.testing.assert_close(torch.unique(E), torch.tensor((20,), device=E.device, dtype=E.dtype))
" >/dev/null 2>&1; then
        echo "✅ Legacy environment is healthy — migrating..."
        mv "$STUDIO_HOME/.venv" "$VENV_DIR"
        echo "   Moved ~/.unsloth/studio/.venv → $VENV_DIR"
        _MIGRATED=true
    else
        echo "⚠️  Legacy environment failed validation — creating fresh environment"
        rm -rf "$STUDIO_HOME/.venv"
    fi
fi

# If an Intel Mac has a stale 3.13 venv from a previous failed install, recreate
# (skip when the user explicitly chose a version via --python)
if [ "$SKIP_TORCH" = true ] && [ "$MAC_INTEL" = true ] && [ -z "$_USER_PYTHON" ] && [ -x "$VENV_DIR/bin/python" ]; then
    _PY_MM=$("$VENV_DIR/bin/python" -c \
        "import sys; print('{}.{}'.format(*sys.version_info[:2]))" 2>/dev/null || echo "")
    if [ "$_PY_MM" != "3.12" ]; then
        echo "  Recreating Intel Mac environment with Python 3.12 (was $_PY_MM)..."
        rm -rf "$VENV_DIR"
    fi
fi

if [ ! -x "$VENV_DIR/bin/python" ]; then
    step "venv" "creating Python ${PYTHON_VERSION} virtual environment"
    substep "$VENV_DIR"
    run_install_cmd "create venv" uv venv "$VENV_DIR" --python "$PYTHON_VERSION"
fi

# Guard against Python 3.13.8 torch import bug on Apple Silicon
# (skip when the user explicitly chose a version via --python)
if [ -z "$_USER_PYTHON" ] && [ "$OS" = "macos" ] && [ "$_ARCH" = "arm64" ]; then
    _PY_VER=$("$VENV_DIR/bin/python" -c \
        "import sys; print('{}.{}.{}'.format(*sys.version_info[:3]))" 2>/dev/null || echo "")
    if [ "$_PY_VER" = "3.13.8" ]; then
        echo "  WARNING: Python 3.13.8 has a known torch import bug."
        echo "  Recreating venv with Python 3.12..."
        rm -rf "$VENV_DIR"
        PYTHON_VERSION="3.12"
        run_install_cmd "recreate venv" uv venv "$VENV_DIR" --python "$PYTHON_VERSION"
    fi
fi

if [ -x "$VENV_DIR/bin/python" ]; then
    step "venv" "using environment"
    substep "${VENV_DIR}"
fi

# Default torch constraint -- tightened for Python 3.13+ on arm64 macOS
# (torch <2.6 has no cp313 macOS arm64 wheels)
TORCH_CONSTRAINT="torch>=2.4,<2.11.0"
if [ "$SKIP_TORCH" = false ] && [ "$OS" = "macos" ] && [ "$_ARCH" = "arm64" ]; then
    _PY_MINOR=$("$VENV_DIR/bin/python" -c \
        "import sys; print(sys.version_info.minor)" 2>/dev/null || echo "0")
    if [ "$_PY_MINOR" -ge 13 ] 2>/dev/null; then
        TORCH_CONSTRAINT="torch>=2.6,<2.11.0"
    fi
fi

# ── Resolve repo root (for --local installs) ──
_REPO_ROOT="$(cd "$(dirname "$0" 2>/dev/null || echo ".")" && pwd)"

# ── Helper: find no-torch-runtime.txt (local repo or site-packages) ──
_find_no_torch_runtime() {
    # Check local repo first (for --local installs)
    if [ -f "$_REPO_ROOT/studio/backend/requirements/no-torch-runtime.txt" ]; then
        echo "$_REPO_ROOT/studio/backend/requirements/no-torch-runtime.txt"
        return
    fi
    # Check inside installed package
    _rt=$(find "$VENV_DIR" -path "*/studio/backend/requirements/no-torch-runtime.txt" -print -quit 2>/dev/null || echo "")
    if [ -n "$_rt" ]; then
        echo "$_rt"
        return
    fi
}

# ── AMD ROCm GPU detection helper ──
# Returns 0 (true) if an actual AMD GPU is present, 1 (false) otherwise.
# Checks rocminfo for gfx[1-9]* (excludes gfx000 CPU agent) and
# amd-smi list for GPU data rows (excludes header-only output).
_has_amd_rocm_gpu() {
    if command -v rocminfo >/dev/null 2>&1 && \
       rocminfo 2>/dev/null | awk '/Name:[[:space:]]*gfx[0-9]/ && !/Name:[[:space:]]*gfx000/{found=1} END{exit !found}'; then
        return 0
    elif command -v amd-smi >/dev/null 2>&1 && \
         amd-smi list 2>/dev/null | awk '/^GPU[[:space:]]*[:\[][[:space:]]*[0-9]/{ found=1 } END{ exit !found }'; then
        return 0
    fi
    return 1
}

# ── NVIDIA usable-GPU helper ──
# Returns 0 (true) only if nvidia-smi is present AND actually lists a GPU.
# Prevents AMD-only hosts with a stale nvidia-smi on PATH from being routed
# into the CUDA branch.
_has_usable_nvidia_gpu() {
    _nvsmi=""
    if command -v nvidia-smi >/dev/null 2>&1; then
        _nvsmi="nvidia-smi"
    elif [ -x "/usr/bin/nvidia-smi" ]; then
        _nvsmi="/usr/bin/nvidia-smi"
    else
        return 1
    fi
    "$_nvsmi" -L 2>/dev/null | awk '/^GPU[[:space:]]+[0-9]+:/{found=1} END{exit !found}'
}

# ── Detect GPU and choose PyTorch index URL ──
# Mirrors Get-TorchIndexUrl in install.ps1.
# On CPU-only machines this returns the cpu index, avoiding the solver
# dead-end where --torch-backend=auto resolves to unsloth==2024.8.
get_torch_index_url() {
    _base="${UNSLOTH_PYTORCH_MIRROR:-https://download.pytorch.org/whl}"
    _base="${_base%/}"
    # macOS: always CPU (no CUDA support)
    case "$(uname -s)" in Darwin) echo "$_base/cpu"; return ;; esac
    # Try nvidia-smi -- require the binary to actually list a usable GPU.
    # Presence of the binary alone (container leftovers, stale driver
    # packages) is not sufficient: otherwise an AMD-only host would
    # silently install CUDA wheels.
    _smi=""
    if _has_usable_nvidia_gpu; then
        if command -v nvidia-smi >/dev/null 2>&1; then
            _smi="nvidia-smi"
        elif [ -x "/usr/bin/nvidia-smi" ]; then
            _smi="/usr/bin/nvidia-smi"
        fi
    fi
    if [ -z "$_smi" ]; then
        # No NVIDIA GPU -- check for AMD ROCm GPU.
        # PyTorch only publishes ROCm wheels for linux-x86_64; skip the
        # ROCm branch entirely on aarch64 / arm64 / other architectures
        # so non-x86_64 Linux hosts fall back cleanly to CPU wheels.
        case "$(uname -m)" in
            x86_64|amd64) : ;;
            *) echo "$_base/cpu"; return ;;
        esac
        if ! _has_amd_rocm_gpu; then
            echo "$_base/cpu"; return
        fi
        # AMD GPU confirmed -- detect ROCm version
        _rocm_tag=""
        _rocm_tag=$({ command -v amd-smi >/dev/null 2>&1 && \
            amd-smi version 2>/dev/null | awk -F'ROCm version: ' \
                'NF>1{gsub(/[^0-9.]/, "", $2); split($2,a,"."); print "rocm"a[1]"."a[2]; ok=1; exit} END{exit !ok}'; } || \
            { [ -r /opt/rocm/.info/version ] && \
                awk -F. '{print "rocm"$1"."$2; exit}' /opt/rocm/.info/version; } || \
            { command -v hipconfig >/dev/null 2>&1 && \
                hipconfig --version 2>/dev/null | awk 'NR==1 && /^[0-9]/{split($1,a,"."); if(a[1]+0>0){print "rocm"a[1]"."a[2]; found=1}} END{exit !found}'; } || \
            { command -v dpkg-query >/dev/null 2>&1 && \
                ver="$(dpkg-query -W -f='${Version}\n' rocm-core 2>/dev/null)" && \
                [ -n "$ver" ] && \
                printf '%s\n' "$ver" | sed 's/^[0-9]*://' | awk -F'[.-]' '{print "rocm"$1"."$2; exit}'; } || \
            { command -v rpm >/dev/null 2>&1 && \
                ver="$(rpm -q --qf '%{VERSION}\n' rocm-core 2>/dev/null)" && \
                [ -n "$ver" ] && \
                printf '%s\n' "$ver" | awk -F'[.-]' '{print "rocm"$1"."$2; exit}'; }) 2>/dev/null
        # Validate _rocm_tag: must match "rocmX.Y" with major >= 1
        case "$_rocm_tag" in
            rocm[1-9]*.[0-9]*) : ;;  # valid (major >= 1)
            *) _rocm_tag="" ;;        # reject malformed (empty, garbled, or major=0)
        esac
        if [ -n "$_rocm_tag" ]; then
            # Minimum supported: ROCm 6.0 (no PyTorch wheels exist for older)
            case "$_rocm_tag" in
                rocm[1-5].*) echo "$_base/cpu"; return ;;
            esac
            # ROCm 7.2 only has torch 2.11.0 which exceeds current bounds
            # (<2.11.0).  Fall back to rocm7.1 index which has torch 2.10.0.
            # Enumerate explicit versions rather than matching rocm6.* so
            # a host on ROCm 6.5 or 6.6 (no PyTorch wheels published) is
            # clipped down to the last supported 6.x (rocm6.4) instead of
            # constructing https://download.pytorch.org/whl/rocm6.5 which
            # returns HTTP 403. PyTorch only ships: rocm5.7, 6.0, 6.1, 6.2,
            # 6.3, 6.4, 7.0, 7.1, 7.2 (and 5.7 is below our minimum).
            # TODO: uncomment rocm7.2 when the torch upper bound is bumped
            # to >=2.11.0.
            case "$_rocm_tag" in
                rocm6.0|rocm6.0.*|rocm6.1|rocm6.1.*|rocm6.2|rocm6.2.*|rocm6.3|rocm6.3.*|rocm6.4|rocm6.4.*|rocm7.0|rocm7.0.*|rocm7.1|rocm7.1.*)
                    echo "$_base/$_rocm_tag" ;;
                rocm6.*)
                    # ROCm 6.5+ (no published PyTorch wheels): clip down
                    # to the last supported 6.x wheel set.
                    echo "$_base/rocm6.4" ;;
                *)
                    # ROCm 7.2+ (including future 10.x+): cap to rocm7.1
                    echo "$_base/rocm7.1" ;;
            esac
            return
        fi
        echo "$_base/cpu"; return
    fi
    # Parse CUDA version from nvidia-smi output (POSIX-safe, no grep -P)
    _cuda_ver=$(LC_ALL=C $_smi 2>/dev/null \
        | sed -n 's/.*CUDA Version:[[:space:]]*\([0-9][0-9]*\.[0-9][0-9]*\).*/\1/p' \
        | head -1)
    if [ -z "$_cuda_ver" ]; then
        echo "[WARN] Could not determine CUDA version from nvidia-smi, defaulting to cu126" >&2
        echo "$_base/cu126"; return
    fi
    _major=${_cuda_ver%%.*}
    _minor=${_cuda_ver#*.}
    if [ "$_major" -ge 13 ]; then echo "$_base/cu130"
    elif [ "$_major" -eq 12 ] && [ "$_minor" -ge 8 ]; then echo "$_base/cu128"
    elif [ "$_major" -eq 12 ] && [ "$_minor" -ge 6 ]; then echo "$_base/cu126"
    elif [ "$_major" -ge 12 ]; then echo "$_base/cu124"
    elif [ "$_major" -ge 11 ]; then echo "$_base/cu118"
    else echo "$_base/cpu"; fi
}

get_radeon_wheel_url() {
    # Only meaningful on Linux. Picks a repo.radeon.com base URL whose listing
    # contains torch wheels. Tries paths like rocm-rel-7.2.1/, rocm-rel-7.2/,
    # rocm-rel-7.1.1/, rocm-rel-7.1/ (AMD publishes both M.m and M.m.p dirs).
    # Accepts both X.Y and X.Y.Z host versions since /opt/rocm/.info/version
    # and hipconfig --version can return either shape.
    case "$(uname -s)" in Linux) ;; *) echo ""; return ;; esac

    # Detect ROCm version (X.Y or X.Y.Z) -- try amd-smi, then
    # /opt/rocm/.info/version, then hipconfig.
    _full_ver=""
    _full_ver=$({ command -v amd-smi >/dev/null 2>&1 && \
        amd-smi version 2>/dev/null | awk -F'ROCm version: ' \
            'NF>1{if(match($2,/[0-9]+\.[0-9]+(\.[0-9]+)?/)){print substr($2,RSTART,RLENGTH); ok=1; exit}} END{exit !ok}'; } || \
        { [ -r /opt/rocm/.info/version ] && \
            awk 'match($0,/[0-9]+\.[0-9]+(\.[0-9]+)?/){print substr($0,RSTART,RLENGTH); found=1; exit} END{exit !found}' /opt/rocm/.info/version; } || \
        { command -v hipconfig >/dev/null 2>&1 && \
            hipconfig --version 2>/dev/null | awk 'NR==1 && match($0,/[0-9]+\.[0-9]+(\.[0-9]+)?/){print substr($0,RSTART,RLENGTH); found=1} END{exit !found}'; }) 2>/dev/null

    # Validate: must be X.Y or X.Y.Z with X >= 1
    case "$_full_ver" in
        [1-9]*.[0-9]*.[0-9]*) : ;;  # X.Y.Z
        [1-9]*.[0-9]*) : ;;          # X.Y
        *) echo ""; return ;;
    esac
    echo "https://repo.radeon.com/rocm/manylinux/rocm-rel-${_full_ver}/"
}

# ── Radeon repo wheel selection helpers ──────────────────────────────────────
# Fetches the Radeon repo directory listing once into _RADEON_LISTING (global).
# _RADEON_PYTAG holds the CPython tag for the running interpreter (e.g. cp312).
# _RADEON_BASE_URL holds the base URL for relative-href resolution.
_RADEON_LISTING=""
_RADEON_PYTAG=""
_RADEON_BASE_URL=""

_radeon_fetch_listing() {
    # Usage: _radeon_fetch_listing BASE_URL
    # Populates _RADEON_LISTING, _RADEON_PYTAG, _RADEON_BASE_URL.
    _RADEON_BASE_URL="$1"
    _RADEON_PYTAG=$("$_VENV_PY" -c "
import sys
print('cp{}{}'.format(sys.version_info.major, sys.version_info.minor))
" 2>/dev/null) || return 1
    if command -v curl >/dev/null 2>&1; then
        _RADEON_LISTING=$(curl -fsSL --max-time 20 "$_RADEON_BASE_URL" 2>/dev/null)
    elif command -v wget >/dev/null 2>&1; then
        _RADEON_LISTING=$(wget -qO- --timeout=20 "$_RADEON_BASE_URL" 2>/dev/null)
    fi
    [ -n "$_RADEON_LISTING" ] || return 1
}

_pick_radeon_wheel() {
    # Usage: _pick_radeon_wheel PACKAGE_NAME
    # Scans $_RADEON_LISTING for the newest wheel whose filename starts exactly
    # with PACKAGE_NAME- and matches _RADEON_PYTAG + linux_x86_64.
    # Prints the full URL (resolving relative hrefs against _RADEON_BASE_URL).
    #
    # POSIX-compliant pipeline: all href parsing, filtering, and version
    # selection is done inside a single awk script rather than reaching
    # for GNU extensions (grep -o, sort -V) that would break under BSD
    # or BusyBox coreutils.
    _pkg="$1"
    [ -n "$_RADEON_LISTING" ] || return 1
    [ -n "$_RADEON_PYTAG"   ] || return 1
    _tag="$_RADEON_PYTAG"
    _href=$(printf '%s\n' "$_RADEON_LISTING" \
        | awk -v pkg="$_pkg" -v tag="$_tag" '
            BEGIN { max_pad = ""; max_url = "" }
            {
                line = $0
                while (match(line, /href="[^"]*"/)) {
                    # Strip the leading href=" (6 chars) and trailing " (1 char)
                    url = substr(line, RSTART + 6, RLENGTH - 7)
                    line = substr(line, RSTART + RLENGTH)

                    # Extract basename, strip query / fragment
                    n = split(url, p, "/")
                    base = p[n]
                    sub(/[?#].*/, "", base)

                    prefix = pkg "-"
                    # Match cpXY-cpXY or cpXY-abi3 with any linux x86_64
                    # platform tag (linux_x86_64, manylinux_2_28_x86_64,
                    # manylinux2014_x86_64, etc.)
                    if (substr(base, 1, length(prefix)) == prefix &&
                            index(base, "-" tag "-") > 0 &&
                            match(base, /x86_64\.whl$/)) {
                        # Extract the version component (first
                        # dotted-number run) and pad each piece so a
                        # plain lexical comparison gives us the newest.
                        if (match(base, /[0-9]+\.[0-9]+(\.[0-9]+)?/)) {
                            ver = substr(base, RSTART, RLENGTH)
                            m = split(ver, v, ".")
                            pad = ""
                            for (i = 1; i <= m; i++)
                                pad = pad sprintf("%08d", v[i])
                            if (pad > max_pad) {
                                max_pad = pad
                                max_url = url
                            }
                        }
                    }
                }
            }
            END { if (max_url != "") print max_url }')
    [ -z "$_href" ] && return 1
    case "$_href" in
        http*) printf '%s\n' "$_href" ;;
        *)     printf '%s\n' "${_RADEON_BASE_URL%/}/${_href#/}" ;;
    esac
}

TORCH_INDEX_URL=$(get_torch_index_url)

# Auto-detect GPU for AMD ROCm based
# get_torch_index_url must have chosen */rocm*
# (gfx in rocminfo or amd-smi list). Then require rocminfo "Marketing Name:.*Radeon".
_amd_gpu_radeon=false
case "$TORCH_INDEX_URL" in
    */rocm*)
        if _has_amd_rocm_gpu && command -v rocminfo >/dev/null 2>&1 && \
           rocminfo 2>/dev/null | grep -q 'Marketing Name:.*Radeon'; then
            _amd_gpu_radeon=true
        fi
        ;;
esac

# ── Print CPU-only hint when no GPU detected ──
case "$TORCH_INDEX_URL" in
    */cpu)
        if [ "$SKIP_TORCH" = false ] && [ "$OS" != "macos" ]; then
            echo ""
            echo "  NOTE: No GPU detected (nvidia-smi and ROCm not found)."
            echo "  Installing CPU-only PyTorch. If you only need GGUF chat/inference,"
            echo "  re-run with --no-torch for a faster, lighter install:"
            echo "    curl -fsSL https://unsloth.ai/install.sh | sh -s -- --no-torch"
            echo "  AMD ROCm users: see https://docs.unsloth.ai/get-started/install-and-update/amd"
            echo ""
        fi
        ;;
    */rocm*)
        echo ""
        if [ "$_amd_gpu_radeon" = true ]; then
            echo "  AMD Radeon + ROCm detected -- installing PyTorch wheels from repo.radeon.com"
        else
            echo "  AMD ROCm detected -- installing ROCm-enabled PyTorch ($TORCH_INDEX_URL)"
        fi
        echo ""
        ;;
esac

# ── Install unsloth directly into the venv (no activation needed) ──
_VENV_PY="$VENV_DIR/bin/python"
if [ "$_MIGRATED" = true ]; then
    # Migrated env: force-reinstall unsloth+unsloth-zoo to ensure clean state
    # in the new venv location, while preserving existing torch/CUDA
    substep "upgrading unsloth in migrated environment..."
    if [ "$SKIP_TORCH" = true ]; then
        # No-torch: install unsloth + unsloth-zoo with --no-deps (current
        # PyPI metadata still declares torch as a hard dep), then install
        # runtime deps (typer, safetensors, transformers, etc.) with --no-deps
        # to prevent transitive torch resolution.
        run_install_cmd "install unsloth (migrated no-torch)" uv pip install --python "$_VENV_PY" --no-deps \
            --reinstall-package unsloth --reinstall-package unsloth-zoo \
            "unsloth>=2026.4.5" unsloth-zoo
        _NO_TORCH_RT="$(_find_no_torch_runtime)"
        if [ -n "$_NO_TORCH_RT" ]; then
            run_install_cmd "install no-torch runtime deps" uv pip install --python "$_VENV_PY" --no-deps -r "$_NO_TORCH_RT"
        fi
    else
        run_install_cmd "install unsloth (migrated)" uv pip install --python "$_VENV_PY" \
            --reinstall-package unsloth --reinstall-package unsloth-zoo \
            "unsloth>=2026.4.5" unsloth-zoo
    fi
    if [ "$STUDIO_LOCAL_INSTALL" = true ]; then
        substep "overlaying local repo (editable)..."
        run_install_cmd "overlay local repo" uv pip install --python "$_VENV_PY" -e "$_REPO_ROOT" --no-deps
    fi
    # AMD ROCm: install bitsandbytes even in migrated environments so
    # existing ROCm installs gain the AMD bitsandbytes build without a
    # fresh reinstall.
    if [ "$SKIP_TORCH" = false ]; then
        case "$TORCH_INDEX_URL" in
            */rocm*)
                _install_bnb_rocm "install bitsandbytes (AMD)" "$_VENV_PY"
                # Repair ROCm torch if overwritten during migrated install
                _has_hip=$("$_VENV_PY" -c "import torch; print(getattr(torch.version,'hip','') or '')" 2>/dev/null || true)
                if [ -z "$_has_hip" ]; then
                    substep "repairing ROCm torch (overwritten by dependency resolution)..."
                    run_install_cmd "repair ROCm torch" uv pip install --python "$_VENV_PY" \
                        "$TORCH_CONSTRAINT" torchvision torchaudio \
                        --index-url "$TORCH_INDEX_URL" \
                        --force-reinstall
                fi
                ;;
        esac
    fi
elif [ -n "$TORCH_INDEX_URL" ]; then
    # Fresh: Step 1 - install torch from explicit index (skip when --no-torch or Intel Mac)
    if [ "$SKIP_TORCH" = true ]; then
        substep "skipping PyTorch (--no-torch or Intel Mac x86_64)." "$C_WARN"
    elif [ "$_amd_gpu_radeon" = true ]; then
        _radeon_url=$(get_radeon_wheel_url)
        if [ -n "$_radeon_url" ]; then
            _radeon_listing_ok=false
            if _radeon_fetch_listing "$_radeon_url" 2>/dev/null; then
                _radeon_listing_ok=true
            else
                # Try shorter X.Y path (AMD publishes both X.Y.Z and X.Y dirs)
                _radeon_url_short=$(printf '%s\n' "$_radeon_url" \
                    | sed 's|rocm-rel-\([0-9]*\)\.\([0-9]*\)\.[0-9]*/|rocm-rel-\1.\2/|')
                if [ "$_radeon_url_short" != "$_radeon_url" ] && \
                   _radeon_fetch_listing "$_radeon_url_short" 2>/dev/null; then
                    _radeon_listing_ok=true
                fi
            fi

            if [ "$_radeon_listing_ok" = true ]; then
                # Require torch, torchvision, torchaudio wheels to all resolve
                # from the Radeon listing. If any is missing for this Python
                # tag, fall through to the standard ROCm index instead of
                # silently mixing Radeon wheels with PyPI defaults.
                _torch_whl=$(_pick_radeon_wheel "torch"       2>/dev/null) || _torch_whl=""
                _tv_whl=$(_pick_radeon_wheel    "torchvision" 2>/dev/null) || _tv_whl=""
                _ta_whl=$(_pick_radeon_wheel    "torchaudio"  2>/dev/null) || _ta_whl=""
                _tri_whl=$(_pick_radeon_wheel   "triton"      2>/dev/null) || _tri_whl=""
                # Sanity-check torch / torchvision / torchaudio are a
                # matching release. The Radeon repo publishes multiple
                # generations simultaneously, so picking the highest-version
                # wheel for each package independently can assemble a
                # mismatched trio (e.g. torch 2.9.1 + torchvision 0.23.0 +
                # torchaudio 2.9.0 from the current rocm-rel-7.2.1 index).
                # Check that torch and torchaudio share the same X.Y public
                # version prefix, and that torchvision's minor correctly
                # pairs with torch's minor (torchvision = torch.minor - 5
                # since torch 2.4 -> torchvision 0.19 -> torch 2.9 ->
                # torchvision 0.24).
                # URL-decode each wheel name so %2B -> + before version
                # extraction. Real Radeon wheel hrefs are percent-encoded
                # (torch-2.10.0%2Brocm7.2.0...), so a plain [+-] terminator
                # in the sed regex below would never match and
                # _radeon_versions_match would stay false for every real
                # listing, silently forcing a fallback to the generic
                # ROCm index.
                _torch_ver=""
                _tv_ver=""
                _ta_ver=""
                if [ -n "$_torch_whl" ]; then
                    _torch_name=$(printf '%s' "${_torch_whl##*/}" | sed 's/%2[Bb]/+/g')
                    _torch_ver=$(printf '%s\n' "$_torch_name" | sed -n 's|^torch-\([0-9][0-9]*\.[0-9][0-9]*\)\(\.[0-9][0-9]*\)\{0,1\}[+-].*|\1|p')
                fi
                if [ -n "$_tv_whl" ]; then
                    _tv_name=$(printf '%s' "${_tv_whl##*/}" | sed 's/%2[Bb]/+/g')
                    _tv_ver=$(printf '%s\n' "$_tv_name" | sed -n 's|^torchvision-\([0-9][0-9]*\.[0-9][0-9]*\)\(\.[0-9][0-9]*\)\{0,1\}[+-].*|\1|p')
                fi
                if [ -n "$_ta_whl" ]; then
                    _ta_name=$(printf '%s' "${_ta_whl##*/}" | sed 's/%2[Bb]/+/g')
                    _ta_ver=$(printf '%s\n' "$_ta_name" | sed -n 's|^torchaudio-\([0-9][0-9]*\.[0-9][0-9]*\)\(\.[0-9][0-9]*\)\{0,1\}[+-].*|\1|p')
                fi
                _radeon_versions_match=false
                if [ -n "$_torch_ver" ] && [ -n "$_tv_ver" ] && [ -n "$_ta_ver" ]; then
                    _torch_major=${_torch_ver%%.*}
                    _torch_minor=${_torch_ver#*.}
                    _ta_major=${_ta_ver%%.*}
                    _ta_minor=${_ta_ver#*.}
                    _tv_major=${_tv_ver%%.*}
                    _tv_minor=${_tv_ver#*.}
                    # torchvision expected minor (e.g. torch 2.9 -> 0.24)
                    _expected_tv_minor=$((_torch_minor + 15))
                    if [ "$_torch_major" = "$_ta_major" ] && \
                       [ "$_torch_minor" = "$_ta_minor" ] && \
                       [ "$_tv_major" = "0" ] && \
                       [ "$_tv_minor" = "$_expected_tv_minor" ]; then
                        _radeon_versions_match=true
                    fi
                fi
                if [ -z "$_torch_whl" ] || [ -z "$_tv_whl" ] || [ -z "$_ta_whl" ] || \
                   [ "$_radeon_versions_match" != true ]; then
                    substep "[WARN] Radeon repo lacks a compatible wheel set for this Python; falling back to ROCm index ($TORCH_INDEX_URL)" "$C_WARN"
                    run_install_cmd "install PyTorch" uv pip install --python "$_VENV_PY" \
                        "$TORCH_CONSTRAINT" torchvision torchaudio \
                        --index-url "$TORCH_INDEX_URL"
                else
                    substep "installing PyTorch from Radeon repo (${_RADEON_BASE_URL})..."
                    # Pass explicit wheel URLs so the matched trio is
                    # installed together. --find-links lets uv discover
                    # the Radeon listing for any local lookup, and PyPI
                    # (not disabled) provides transitive deps like
                    # filelock / sympy / networkx which are not in the
                    # Radeon listing.
                    if [ -n "$_tri_whl" ]; then
                        run_install_cmd "install triton + PyTorch" uv pip install --python "$_VENV_PY" \
                            --find-links "$_RADEON_BASE_URL" \
                            "$_tri_whl" "$_torch_whl" "$_tv_whl" "$_ta_whl"
                    else
                        run_install_cmd "install PyTorch" uv pip install --python "$_VENV_PY" \
                            --find-links "$_RADEON_BASE_URL" \
                            "$_torch_whl" "$_tv_whl" "$_ta_whl"
                    fi
                fi
            else
                substep "[WARN] Radeon repo unavailable; falling back to ROCm index ($TORCH_INDEX_URL)" "$C_WARN"
                run_install_cmd "install PyTorch" uv pip install --python "$_VENV_PY" \
                    "$TORCH_CONSTRAINT" torchvision torchaudio \
                    --index-url "$TORCH_INDEX_URL"
            fi
        else
            substep "[WARN] Radeon GPU detected but could not detect full ROCm version; falling back to ROCm index" "$C_WARN"
            run_install_cmd "install PyTorch" uv pip install --python "$_VENV_PY" \
                "$TORCH_CONSTRAINT" torchvision torchaudio \
                --index-url "$TORCH_INDEX_URL"
        fi
    else
        substep "installing PyTorch ($TORCH_INDEX_URL)..."
        run_install_cmd "install PyTorch" uv pip install --python "$_VENV_PY" "$TORCH_CONSTRAINT" torchvision torchaudio \
            --index-url "$TORCH_INDEX_URL"
    fi
    # AMD ROCm: install bitsandbytes (once, after torch, for all ROCm paths).
    # Gate on SKIP_TORCH=false so a user running with --no-torch on a ROCm
    # host stays in GGUF-only mode rather than pulling in bitsandbytes,
    # which is only useful once torch is present for training.
    if [ "$SKIP_TORCH" = false ]; then
        case "$TORCH_INDEX_URL" in
            */rocm*)
                _install_bnb_rocm "install bitsandbytes (AMD)" "$_VENV_PY"
                ;;
        esac
    fi
    # Fresh: Step 2 - install unsloth, preserving pre-installed torch
    substep "installing unsloth (this may take a few minutes)..."
    if [ "$SKIP_TORCH" = true ]; then
        # No-torch: install unsloth + unsloth-zoo with --no-deps, then
        # runtime deps (typer, safetensors, transformers, etc.) with --no-deps.
        run_install_cmd "install unsloth (no-torch)" uv pip install --python "$_VENV_PY" --no-deps \
            --upgrade-package unsloth --upgrade-package unsloth-zoo \
            "unsloth>=2026.4.5" unsloth-zoo
        _NO_TORCH_RT="$(_find_no_torch_runtime)"
        if [ -n "$_NO_TORCH_RT" ]; then
            run_install_cmd "install no-torch runtime deps" uv pip install --python "$_VENV_PY" --no-deps -r "$_NO_TORCH_RT"
        fi
        if [ "$STUDIO_LOCAL_INSTALL" = true ]; then
            substep "overlaying local repo (editable)..."
            run_install_cmd "overlay local repo" uv pip install --python "$_VENV_PY" -e "$_REPO_ROOT" --no-deps
        fi
    elif [ "$STUDIO_LOCAL_INSTALL" = true ]; then
        run_install_cmd "install unsloth (local)" uv pip install --python "$_VENV_PY" \
            --upgrade-package unsloth "unsloth>=2026.4.5" unsloth-zoo
        substep "overlaying local repo (editable)..."
        run_install_cmd "overlay local repo" uv pip install --python "$_VENV_PY" -e "$_REPO_ROOT" --no-deps
    else
        run_install_cmd "install unsloth" uv pip install --python "$_VENV_PY" \
            --upgrade-package unsloth "$PACKAGE_NAME"
    fi
    # AMD ROCm: repair torch if the unsloth/unsloth-zoo install pulled in
    # CUDA torch from PyPI, overwriting the ROCm wheels installed in Step 1.
    if [ "$SKIP_TORCH" = false ]; then
        case "$TORCH_INDEX_URL" in
            */rocm*)
                _has_hip=$("$_VENV_PY" -c "import torch; print(getattr(torch.version,'hip','') or '')" 2>/dev/null || true)
                if [ -z "$_has_hip" ]; then
                    substep "repairing ROCm torch (overwritten by dependency resolution)..."
                    run_install_cmd "repair ROCm torch" uv pip install --python "$_VENV_PY" \
                        "$TORCH_CONSTRAINT" torchvision torchaudio \
                        --index-url "$TORCH_INDEX_URL" \
                        --force-reinstall
                fi
                ;;
        esac
    fi
else
    # Fallback: GPU detection failed to produce a URL -- let uv resolve torch
    substep "installing unsloth (this may take a few minutes)..."
    if [ "$STUDIO_LOCAL_INSTALL" = true ]; then
        run_install_cmd "install unsloth (auto torch backend)" uv pip install --python "$_VENV_PY" unsloth-zoo "unsloth>=2026.4.5" --torch-backend=auto
        substep "overlaying local repo (editable)..."
        run_install_cmd "overlay local repo" uv pip install --python "$_VENV_PY" -e "$_REPO_ROOT" --no-deps
    else
        run_install_cmd "install unsloth (auto torch backend)" uv pip install --python "$_VENV_PY" "$PACKAGE_NAME" --torch-backend=auto
    fi
fi

# ── Run studio setup ──
# When --local, use the repo's own setup.sh directly.
# Otherwise, find it inside the installed package.
SETUP_SH=""
if [ "$STUDIO_LOCAL_INSTALL" = true ] && [ -f "$_REPO_ROOT/studio/setup.sh" ]; then
    SETUP_SH="$_REPO_ROOT/studio/setup.sh"
fi

if [ -z "$SETUP_SH" ] || [ ! -f "$SETUP_SH" ]; then
    SETUP_SH=$("$VENV_DIR/bin/python" -c "
import importlib.resources
print(importlib.resources.files('studio') / 'setup.sh')
" 2>/dev/null || echo "")
fi

# Fallback: search site-packages
if [ -z "$SETUP_SH" ] || [ ! -f "$SETUP_SH" ]; then
    SETUP_SH=$(find "$VENV_DIR" -path "*/studio/setup.sh" -print -quit 2>/dev/null || echo "")
fi

if [ -z "$SETUP_SH" ] || [ ! -f "$SETUP_SH" ]; then
    echo "❌ ERROR: Could not find studio/setup.sh in the installed package."
    exit 1
fi

# Ensure the venv's Python is on PATH so setup.sh can find it.
VENV_ABS_BIN="$(cd "$VENV_DIR/bin" && pwd)"
if [ -n "$VENV_ABS_BIN" ]; then
    export PATH="$VENV_ABS_BIN:$PATH"
fi

if ! command -v bash >/dev/null 2>&1; then
    step "setup" "bash is required to run studio setup" "$C_ERR"
    substep "Please install bash and re-run install.sh"
    exit 1
fi

step "setup" "running unsloth studio update..."
# install.sh already installs base packages (unsloth + unsloth-zoo) and
# no-torch-runtime.txt above, so tell install_python_stack.py to skip
# the base step to avoid redundant reinstallation.
_SKIP_BASE=1
# Run setup.sh outside set -e so that a llama.cpp build failure (exit 1)
# does not skip PATH setup, shortcuts, and launch below.  We capture the
# exit code and propagate it after post-install steps finish.
_SETUP_EXIT=0
if [ "$STUDIO_LOCAL_INSTALL" = true ]; then
    SKIP_STUDIO_BASE="$_SKIP_BASE" \
    STUDIO_PACKAGE_NAME="$PACKAGE_NAME" \
    STUDIO_LOCAL_INSTALL=1 \
    STUDIO_LOCAL_REPO="$_REPO_ROOT" \
    UNSLOTH_NO_TORCH="$SKIP_TORCH" \
    bash "$SETUP_SH" </dev/null || _SETUP_EXIT=$?
else
    SKIP_STUDIO_BASE="$_SKIP_BASE" \
    STUDIO_PACKAGE_NAME="$PACKAGE_NAME" \
    UNSLOTH_NO_TORCH="$SKIP_TORCH" \
    bash "$SETUP_SH" </dev/null || _SETUP_EXIT=$?
fi

# ── Make 'unsloth' available globally via ~/.local/bin ──
mkdir -p "$HOME/.local/bin"
ln -sf "$VENV_DIR/bin/unsloth" "$HOME/.local/bin/unsloth"

_LOCAL_BIN="$HOME/.local/bin"
case ":$PATH:" in
    *":$_LOCAL_BIN:"*) ;;  # already on PATH
    *)
        _SHELL_PROFILE=""
        if [ -n "${ZSH_VERSION:-}" ] || [ "$(basename "${SHELL:-}")" = "zsh" ]; then
            _SHELL_PROFILE="$HOME/.zshrc"
        elif [ -f "$HOME/.bashrc" ]; then
            _SHELL_PROFILE="$HOME/.bashrc"
        elif [ -f "$HOME/.profile" ]; then
            _SHELL_PROFILE="$HOME/.profile"
        fi

        if [ -n "$_SHELL_PROFILE" ]; then
            if ! grep -q '\.local/bin' "$_SHELL_PROFILE" 2>/dev/null; then
                echo '' >> "$_SHELL_PROFILE"
                echo '# Added by Unsloth installer' >> "$_SHELL_PROFILE"
                echo 'export PATH="$HOME/.local/bin:$PATH"' >> "$_SHELL_PROFILE"
                step "path" "added ~/.local/bin to PATH in $_SHELL_PROFILE"
            fi
        fi
        export PATH="$_LOCAL_BIN:$PATH"
        ;;
esac

create_studio_shortcuts "$VENV_ABS_BIN/unsloth" "$OS"

# If setup.sh failed, report and exit now.
# PATH and shortcuts are already set up so the user can fix and retry.
if [ "$_SETUP_EXIT" -ne 0 ]; then
    echo ""
    step "error" "studio setup failed (exit code $_SETUP_EXIT)" "$C_ERR"
    substep "Check the output above for details, then re-run:"
    if [ "$STUDIO_LOCAL_INSTALL" = true ]; then
        substep "  unsloth studio update --local"
    else
        substep "  unsloth studio update"
    fi
    echo ""
    exit "$_SETUP_EXIT"
fi

echo ""
printf "  ${C_TITLE}%s${C_RST}\n" "Unsloth Studio installed!"
printf "  ${C_DIM}%s${C_RST}\n" "$RULE"
echo ""

# Launch studio automatically in interactive terminals;
# in non-interactive environments (Docker, CI, cloud-init) just print instructions.
if [ -t 1 ]; then
    step "launch" "starting Unsloth Studio..."
    "$VENV_DIR/bin/unsloth" studio -H 0.0.0.0 -p 8888
    _LAUNCH_EXIT=$?
    if [ "$_LAUNCH_EXIT" -ne 0 ] && [ "$_MIGRATED" = true ]; then
        echo ""
        echo "⚠️  Unsloth Studio failed to start after migration."
        echo "   Your migrated environment may be incompatible."
        echo "   To fix, remove the environment and reinstall:"
        echo ""
        echo "   rm -rf $VENV_DIR"
        echo "   curl -fsSL https://unsloth.ai/install.sh | sh"
        echo ""
    fi
    exit "$_LAUNCH_EXIT"
else
    step "launch" "manual commands:"
    substep "unsloth studio -H 0.0.0.0 -p 8888"
    substep "or activate env first:"
    substep "source ${VENV_DIR}/bin/activate"
    substep "unsloth studio -H 0.0.0.0 -p 8888"
    echo ""
fi