#!/bin/bash

# This script configures the environment to run 'greptime' with the required Python version

# This script should be compatible both in Linux and macOS
OS_TYPE="$(uname)"
readonly OS_TYPE

check_command_existence() {
    command -v "$1" &> /dev/null
}

get_python_version() {
    case "$OS_TYPE" in
        Darwin)
            otool -L $GREPTIME_BIN_PATH | grep -o 'Python.framework/Versions/3.[0-9]\+/Python' | grep -o '3.[0-9]\+'
            ;;
        Linux)
            ldd $GREPTIME_BIN_PATH | grep -o 'libpython3\.[0-9]\+' | grep -o '3\.[0-9]\+'
            ;;
        *)
            echo "Unsupported OS type: $OS_TYPE"
            exit 1
            ;;
    esac
}

setup_virtualenv() {
    local req_py_version="$1"
    local env_name="GreptimeTmpVenv$req_py_version"
    virtualenv --python=python"$req_py_version" "$env_name"
    source "$env_name/bin/activate"
}

setup_conda_env() {
    local req_py_version="$1"
    local conda_base
    conda_base=$(conda info --base) || { echo "Error obtaining conda base directory"; exit 1; }
    . "$conda_base/etc/profile.d/conda.sh"

    if ! conda list --name "GreptimeTmpPyO3Env$req_py_version" &> /dev/null; then
        conda create --yes --name "GreptimeTmpPyO3Env$req_py_version" python="$req_py_version"
    fi

    conda activate "GreptimeTmpPyO3Env$req_py_version"
}

GREPTIME_BIN_PATH="./greptime"
YES="false"

usage() {
  echo "Usage:"
  echo "  $0 -f <greptime-bin-path> [-y] <args-pass-to-greptime>"
  echo "Set $PY_ENV_MAN to 1 to use virtualenv, 2 to use conda"
  exit 1
}

function parse_args() {
  while getopts ":f:y" opt; do
    case $opt in
      f)
        GREPTIME_BIN_PATH=$OPTARG
        ;;
      y)
        YES="yes"
        ;;
      \?)
        echo "Invalid option: -$OPTARG" >&2
        exit 1
        ;;
      :)
        echo "Option -$OPTARG requires an argument." >&2
        exit 1
        ;;
    esac
  done

  shift $((OPTIND -1))

  REST_ARGS=$*

  if [ -z "$GREPTIME_BIN_PATH" ]; then
    usage
  fi

  echo "Run greptime binary at '$GREPTIME_BIN_PATH' (yes=$YES)..."
  echo "The args pass to greptime: '$REST_ARGS'"
}

# Set library path and pass all arguments to greptime to run it
execute_greptime() {
    if [[ "$OS_TYPE" == "Darwin" ]]; then
        DYLD_LIBRARY_PATH="${CONDA_PREFIX:-$PREFIX}/lib:${LD_LIBRARY_PATH:-}" $GREPTIME_BIN_PATH $@
    elif [[ "$OS_TYPE" == "Linux" ]]; then
        LD_LIBRARY_PATH="${CONDA_PREFIX:-$PREFIX}/lib:${LD_LIBRARY_PATH:-}" $GREPTIME_BIN_PATH $@
    fi
}

main() {
    parse_args $@

    local req_py_version
    req_py_version=$(get_python_version)
    readonly req_py_version

    if [[ -z "$req_py_version" ]]; then
        if $GREPTIME_BIN_PATH --version &> /dev/null; then
            $GREPTIME_BIN_PATH $REST_ARGS
        else
            echo "The 'greptime' binary is not valid or encountered an error."
            $GREPTIME_BIN_PATH --version
            exit 1
        fi
        return
    fi

    echo "The required version of Python shared library is $req_py_version"

    # if YES exist, assign it to yn, else read from stdin
    if [[ -z "$YES" ]]; then
        echo "Now this script will try to install or find correct Python Version"
        echo "Do you want to continue? (yes/no): "
        read -r yn
    else
        yn="$YES"
    fi
    case $yn in
        [Yy]* ) ;;
        [Nn]* ) exit;;
        * ) echo "Please answer yes or no.";;
    esac

    # if USE_ENV exist, assign it to option
    # else read from stdin
    if [[ -z "$PY_ENV_MAN" ]]; then
        echo "Do you want to use virtualenv or conda? (virtualenv(1)/conda(2)): "
        read -r option
    else
        option="$PY_ENV_MAN"
    fi
    
    case $option in 
        1) 
        setup_virtualenv "$req_py_version"
        ;;
        2) 
        setup_conda_env "$req_py_version"
        ;;
        *) 
        echo "Please input 1 or 2"; exit 1
        ;;
    esac

    execute_greptime $REST_ARGS
}

main "$@"