Arch: python.sh [auto venv activation and pyw support for terminal-less windows]

#!/bin/bash

# Version 24 — AI Enhanced™ Edition

# Unified Python launcher for Linux
#
# BEHAVIOR:
#     *.pyw → run inline, open terminal only on error
#     *.py  → always open terminal, run Python inside terminal
#
# FEATURES:
#     - Auto activation of venv-installed libraries (script-local, cwd-local, global)
#     - Correct error reporting to oh-my-posh (useful if your theme displays status codes), and terminal "Up arrow key" history will contain the command that ran the script.
#     - rcfile auto-cleanup (no leftover /tmp files)
#     - *.pyw script support (for GUI/Tkinter and headless scripts if ye prefer invisible ghost scripts running in the background)
#
# INSTALL:
#     1. $ sudo cp ./python.sh /usr/local/bin/
#     2. $ sudo chmod +x /usr/local/bin/python.sh
#
# USAGE:
#     $ python.sh
#     $ python.sh ./Script.py
#     $ python.sh ./Script.pyw

# Dolphin Configuration:    <-- So you can double click .py and .pyw files to run them.
#
#     Open Dolphin, right-click any .py file > Properties > Open With > Click Change...
#         Filename Patterns:
#             Click "Add..."
#             Extension: *.pyw
#             Click OK
#
#         Application Preference Order:
#             Click "Add..."
#                 Click [Open file dialog] button > /usr/local/bin/python.sh
#                 [x] Remember application association for all files of type "Python 3 script" (text/x-python3)
#                 NOTE: "python.sh" needs to be the topmost item in the list for double clicked scripts to run with it.
#                       If it isn't then click select "python.sh" and click "Move Up" until it is.
#         Click Apply.
#         Click OK.

# KDE Menu Editor Configuration:    <-- So you can create shortcuts to *.py and *.pyw scripts.
#
#     Click New > New Item...
#     Name: <Script Name>
#     Icon: <Path to icon.svg>
#     Program: /usr/local/bin/python.sh
#     Command-Line Arguments: <Path to script.py> or <Path to script.pyw>
#     [ ] Enable launch feedback

# Offtopic notes for creating ~/.venv and installing python libraries there with pip:
#
#     Venv (virtual environment) creation:
#         $ rm -r ~/.venv                  <-- Remove any existing venv folder at the destination.
#         $ python3 -m venv ~/.venv        <-- Needs to be done on a linux partition (not ntfs apparently) or else "which pip" returns "/usr/bin/pip".
#         $ source ~/.venv/bin/activate    <-- Activate the venv.
#         $ which python                   <-- Verify python is ~/.venv/bin/python
#         $ which pip                      <-- Verify pip is ~/.venv/bin/pip
#
#     Install Python libraries into the active .venv with pip:
#         $ source ~/.venv/bin/activate    <-- Activate the venv.
#         $ pip install keyboard pyttsx3
#
#     Making my scripts importable from other scripts:    <-- This new venv approach won't break when updating python versions.
#         $ source ~/.venv/bin/activate    <-- Activate the venv.
#         $ SITEDIR=$(python -c "import sys; print([p for p in sys.path if 'site-packages' in p][0])")    <-- NOTE: The typical command for this doesn't work with venv: $ SITEDIR=$(python -m site --user-site)
#         $ mkdir -p "$SITEDIR"            <-- Create site directory if it doesn't exist.
#         $ echo "/media/D/Users/Wolf/Files/Archives/Scripts/Python" >> "$SITEDIR/wolf-scripts.pth"
#         $ python -m site                 <-- You should see the path you just added in this commands output.
#
#     Running python scripts from the terminal that rely on venv installed libraries:
#         $ source ~/.venv/bin/activate
#         $ python myscript.py
#
#         Or
#
#         $ python.sh myscript.py    <-- Relying on the script.

###############################################
# VENV RESOLUTION
###############################################

# Try three possible venv locations in priority order:
# 1. Script directory's .venv
# 2. Current directory's .venv
# 3. Global ~/.venv
for d in "$(dirname "$(readlink -f "$1" 2>/dev/null)")/.venv" "./.venv" "$HOME/.venv"; do
    # If activate script exists, source it and stop searching.
    [ -f "$d/bin/activate" ] && source "$d/bin/activate" && break
done

###############################################
# TERMINAL DETECTION
###############################################

# Detect the first available terminal emulator.
# Each terminal has its own syntax for executing a command.
for t in kitty konsole alacritty wezterm gnome-terminal xfce4-terminal; do
    if command -v "$t" &>/dev/null; then
        case "$t" in
            kitty|konsole|alacritty)
                TERM=("$t" -e) ;;  # These use "-e <cmd>".
            wezterm)
                TERM=(wezterm start --) ;;  # WezTerm uses "start -- <cmd>".
            gnome-terminal)
                TERM=(gnome-terminal --) ;;  # GNOME Terminal uses "-- <cmd>".
            xfce4-terminal)
                TERM=(xfce4-terminal --execute) ;;  # XFCE Terminal uses "--execute <cmd>".
        esac
        break
    fi
done

# If no terminal found, abort.
[ -z "$TERM" ] && echo "No terminal" && exit 1

###############################################
# NO ARGUMENTS → OPEN PYTHON REPL
###############################################

# Running the launcher with no arguments opens an interactive Python session.
[ $# -eq 0 ] && exec "${TERM[@]}" python

###############################################
# SCRIPT PATH + ARGUMENT RESOLUTION
###############################################

# Resolve script path even if filename contains spaces.
# We progressively join tokens until we find a valid file.
_find() {
    local a=("$@") n=${#a[@]}
    for ((i=1;i<=n;i++)); do
        local p="${a[*]:0:i}" # Join tokens 0..i-1 with spaces.
        if [ -e "$p" ]; then
            SCRIPT=$(readlink -f "$p") # Resolve absolute path.
            ARGS=("${a[@]:i}") # Remaining tokens are arguments.
            return
        fi
    done
    # Fallback: treat first token as script.
    SCRIPT=$(readlink -f "${a[0]}")
    ARGS=("${a[@]:1}")
}
_find "$@"

# Quote arguments safely for shell injection.
# This block is to prevent the creation of an '' empty string arg to the script.
# printf '%q ' on a zero-length array still runs the format once and
# quotes a "missing" arg as an empty string, i.e. it emits the literal
# token '' instead of nothing. Left unguarded, that stray '' gets embedded
# in the generated rc file / inline command line and is then parsed as a
# genuine (spurious) empty-string argument to the Python script.
# Guard it here so 0 args results in an empty ARGS_Q.
if [ ${#ARGS[@]} -gt 0 ]; then
    ARGS_Q="$(printf '%q ' "${ARGS[@]}")"
else
    ARGS_Q=""
fi

###############################################
# .PYW → INLINE EXECUTION (HEADLESS)
###############################################

# Windows-style behavior: .pyw runs without opening a terminal, unless an error occurs.
if [[ "${1,,}" == *.pyw ]]; then

    # Run Python inline and capture output + exit code.
    out=$(PYTHON_COLORS=1 FORCE_COLOR=1 python -- "$SCRIPT" $ARGS_Q 2>&1)
    st=$?

    # If error, open terminal to display error and drop into prompt.
    if (( st != 0 )); then

        # Create temporary rcfile for bash --init-file.
        rc=$(mktemp)

        cat > "$rc" <<EOF
# Source user's shell configuration.
[ -f ~/.bashrc ] && source ~/.bashrc

# Print Python error output + blank line.
printf "%s\n\n" "$out"

# Export exit code for oh-my-posh.
export PROMPT_LAST_EXIT=$st

# Insert clean history entry (no stray '' on the end).
if [ ${#ARGS[@]} -gt 0 ]; then
    history -s "python -- \"$SCRIPT\" $ARGS_Q"
else
    history -s "python -- \"$SCRIPT\""
fi

# Delete this rcfile now that it has finished executing.
rm -f "\$BASH_SOURCE" >/dev/null 2>&1 || true

# Exit with Python's exit code so oh-my-posh detects failure.
(exit $st)
EOF

        # Open terminal running the rcfile.
        exec "${TERM[@]}" bash --init-file "$rc"
    fi

    # Inline execution exit code.
    exit $st
fi

###############################################
# .PY → ALWAYS OPEN TERMINAL
###############################################

# Windows-style behavior: .py always opens a console window.
rc=$(mktemp)

cat > "$rc" <<EOF
# Source user's shell configuration.
[ -f ~/.bashrc ] && source ~/.bashrc

# Run Python inside terminal (streams output live).
PYTHON_COLORS=1 FORCE_COLOR=1 python -- "$SCRIPT" $ARGS_Q
st=\$?

# Always add a blank line after Python output.
echo

# Export exit code for oh-my-posh.
export PROMPT_LAST_EXIT=\$st

# Insert clean history entry (no stray '' on the end).
if [ ${#ARGS[@]} -gt 0 ]; then
    history -s "python -- \"$SCRIPT\" $ARGS_Q"
else
    history -s "python -- \"$SCRIPT\""
fi

# Delete this rcfile now that it has finished executing.
rm -f "\$BASH_SOURCE" >/dev/null 2>&1 || true

# Exit with Python's exit code so oh-my-posh detects failure/success.
(exit \$st)
EOF

# Launch terminal running the rcfile.
exec "${TERM[@]}" bash --init-file "$rc"