#!/usr/bin/bash

# Author: Garuda Linux
# Adopted for Snigdha OS

set -euo pipefail  # Enable strict error handling to ensure errors are caught

LAUNCH_TERMINAL_SHELL="bash"  # Default shell to launch in the terminal

# Usage function to display how the script is used
usage() {
    echo "Usage: ${0##*/} [options] [command]"
    echo
    echo "Options:"
    echo "    -s [shell]         Change shell to [shell] (default: bash)"
    echo "    -h                 Show this help message"
    echo
    echo "Example:"
    echo "    ${0##*/} -s zsh 'echo Hello, World!'"
    echo "    ${0##*/} -h"
    exit 1  # Exit after displaying the usage information
}

# Parse options and arguments
opts="s:h"  # Define the options we expect
while getopts "${opts}" arg; do  # Loop through each option provided
    case "${arg}" in
        s) LAUNCH_TERMINAL_SHELL="$OPTARG" ;;  # Set the shell if provided with -s
        h) usage ;;  # Show usage if -h is provided
        ?) usage ;;  # Catch any invalid options and show usage
        *)
            echo "Invalid option: ${arg}"
            usage
            ;;
    esac
done

# Shift away the processed options, leaving only the command
shift $((OPTIND - 1))

# Ensure a command is provided
if [ $# -eq 0 ]; then
    echo "Error: No command provided."
    usage  # Show usage if no command is provided
fi

# Create temporary files to store shell scripts
initfile=$(mktemp)  # Temp file to store the initialization script
codefile=$initfile  # Initially, set codefile to the initfile

# Generate the initial shell script
echo "#!/usr/bin/env bash" > "$initfile"  # Start the script with bash

# If the user specifies a shell, use it instead of bash
if [ "$LAUNCH_TERMINAL_SHELL" != "bash" ]; then
    codefile=$(mktemp)  # Create another temp file for the specified shell
    echo "$LAUNCH_TERMINAL_SHELL $codefile" >> "$initfile"  # Add shell command to initfile
fi

# Write the user's command into the code file
echo "$1" >> "$codefile"  # Add the user command to the code file
chmod +x "$initfile"  # Make the initfile executable

# Define the command that will be run in the terminal
cmd="$initfile"

# Define a dictionary of supported terminal emulators and their commands
declare -A terminals=(
    ["alacritty"]="alacritty -e bash -c \"$cmd\" || LIBGL_ALWAYS_SOFTWARE=1 alacritty -e bash -c \"$cmd\""
    ["konsole"]="konsole --noclose -e bash -c \"$cmd\""
    ["kgx"]="kgx -- bash -c \"$cmd\""
    ["gnome-terminal"]="gnome-terminal --wait -- bash -c \"$cmd\""
    ["xfce4-terminal"]="xfce4-terminal --disable-server --command bash -c \"$cmd\""
    ["qterminal"]="qterminal -e bash -c \"$cmd\""
    ["lxterminal"]="lxterminal -e bash -c \"$cmd\""
    ["mate-terminal"]="mate-terminal --disable-factory -e bash -c \"$cmd\""
    ["xterm"]="xterm -e bash -c \"$cmd\""
    ["foot"]="foot -T launch-terminal -e bash -c \"$cmd\""
)

# Define an ordered list of terminals to try
declare -a term_order=(
    "alacritty" "konsole" "kgx" "gnome-terminal" "mate-terminal"
    "xfce4-terminal" "qterminal" "lxterminal" "xterm" "foot"
)

# Select the terminal based on the desktop environment
terminal=""
case "$XDG_CURRENT_DESKTOP" in
    KDE) terminal="konsole" ;;  # If in KDE, try Konsole
    GNOME)
        if command -v "kgx" &> /dev/null; then
            terminal="kgx"  # If KGX is available, use it for GNOME
        else
            terminal="gnome-terminal"  # Fallback to gnome-terminal if KGX is not available
        fi
        ;;
    XFCE) terminal="xfce4-terminal" ;;  # If in XFCE, use xfce4-terminal
    LXQt) terminal="qterminal" ;;  # For LXQt, use qterminal
    MATE) terminal="mate-terminal" ;;  # For MATE, use mate-terminal
    *)
        for i in "${term_order[@]}"; do
            if command -v "$i" &> /dev/null; then
                terminal="$i"  # Try to find any terminal from the list
                break
            fi
        done
        ;;
esac

# If no terminal emulator is found, notify and exit
if [ -z "$terminal" ]; then
    notify-send -t 15000 --app-name="Snigdha OS" "No terminal installed" \
        "No supported terminal emulator is installed. Please install a terminal emulator like Alacritty."
    exit 1  # Exit if no terminal is found
fi

# Debugging information: Display selected terminal and command
echo "Selected terminal: $terminal"
echo "Command to execute: ${terminals[$terminal]}"

# Special handling for kgx to ensure proper behavior
if [ "$terminal" = "kgx" ]; then
    sed -i '2i sleep 0.1' "$initfile"  # Add a small sleep to avoid issues
    echo 'kill -SIGINT $PPID' >> "$initfile"  # Send SIGINT to the parent process to close KGX
fi

# Run the selected terminal with the command
exitcode=0  # Default exit code
eval "${terminals[$terminal]}" || exitcode=$?  # Run the terminal command and capture exit code

# Clean up temporary files
rm "$initfile"  # Remove the initial script
if [ "$codefile" != "$initfile" ]; then
    rm "$codefile"  # Remove the code file if it's different from the initfile
fi

# Exit handling
if [ "$exitcode" -eq 0 ]; then
    echo "Terminal executed the command successfully."  # Inform user of success
elif [ "$exitcode" -ne 130 ]; then
    echo "Error: Terminal launch failed with exit code $exitcode"  # Inform user of failure
    exit "$exitcode"  # Exit with the error code if terminal launch failed
fi