#!/bin/bash

set -e

# Optional: Import test library
source dev-container-features-test-lib

USERNAME="automatic"
echo -e "\nRVM version installed previously by ruby feature ..."
check "rvm" rvm --version
check "ruby" ruby -v

trap 'echo "Last executed command failed at line ${LINENO}"' ERR

RVM_GPG_KEYS="409B6B1796C275462A1703113804BB82D39DC0E3 7D2BAF1CF37B13E2069D6956105BD0E739499BDB"

# Clean up
rm -rf /var/lib/apt/lists/*

# Determine the appropriate non-root user
if [ "${USERNAME}" = "auto" ] || [ "${USERNAME}" = "automatic" ]; then
    USERNAME=""
    POSSIBLE_USERS=("vscode" "node" "codespace" "$(awk -v val=1000 -F ":" '$3==val{print $1}' /etc/passwd)")
    for CURRENT_USER in "${POSSIBLE_USERS[@]}"; do
        if id -u ${CURRENT_USER} > /dev/null 2>&1; then
            USERNAME=${CURRENT_USER}
            break
        fi
    done
    if [ "${USERNAME}" = "" ]; then
        USERNAME=root
    fi
elif [ "${USERNAME}" = "none" ] || ! id -u ${USERNAME} > /dev/null 2>&1; then
    USERNAME=root
fi

# Ensure apt is in non-interactive to avoid prompts
export DEBIAN_FRONTEND=noninteractive

architecture="$(uname -m)"
if [ "${architecture}" != "amd64" ] && [ "${architecture}" != "x86_64" ] && [ "${architecture}" != "arm64" ] && [ "${architecture}" != "aarch64" ]; then
    echo "(!) Architecture $architecture unsupported"
    exit 1
fi

apt_get_update()
{
    if [ "$(find /var/lib/apt/lists/* | wc -l)" = "0" ]; then
        echo "Running apt-get update..."
        apt-get update -y
    fi
}

# Checks if packages are installed and installs them if not
check_packages() {
    if ! dpkg -s "$@" > /dev/null 2>&1; then
        apt_get_update
        apt-get -y install --no-install-recommends "$@"
    fi
}

# Get the list of GPG key servers that are reachable
get_gpg_key_servers() {
    declare -A keyservers_curl_map=(
        ["hkp://keyserver.ubuntu.com"]="http://keyserver.ubuntu.com:11371"
        ["hkp://keyserver.ubuntu.com:80"]="http://keyserver.ubuntu.com"
        ["hkps://keys.openpgp.org"]="https://keys.openpgp.org"
        ["hkp://keyserver.pgp.com"]="http://keyserver.pgp.com:11371"
    )

    local curl_args=""
    local keyserver_reachable=false  # Flag to indicate if any keyserver is reachable

    if [ ! -z "${KEYSERVER_PROXY}" ]; then
        curl_args="--proxy ${KEYSERVER_PROXY}"
    fi

    for keyserver in "${!keyservers_curl_map[@]}"; do
        local keyserver_curl_url="${keyservers_curl_map[${keyserver}]}"
        if curl -s ${curl_args} --max-time 5 ${keyserver_curl_url} > /dev/null; then
            echo "keyserver ${keyserver}"
            keyserver_reachable=true
        else
            echo "(*) Keyserver ${keyserver} is not reachable." >&2
        fi
    done

    if ! $keyserver_reachable; then
        echo "(!) No keyserver is reachable." >&2
        exit 1
    fi
}

# Import the specified key in a variable name passed in as 
receive_gpg_keys() {
    local keys=${!1}
    local keyring_args=""
    if [ ! -z "$2" ]; then
        keyring_args="--no-default-keyring --keyring \"$2\""
    fi

    # Install curl
    if ! type curl > /dev/null 2>&1; then
        check_packages curl
    fi

    # Use a temporary location for gpg keys to avoid polluting image
    export GNUPGHOME="/tmp/tmp-gnupg"
    mkdir -p ${GNUPGHOME}
    chmod 700 ${GNUPGHOME}
    echo -e "disable-ipv6\n$(get_gpg_key_servers)" | tee ${GNUPGHOME}/dirmngr.conf > /dev/null
    # GPG key download sometimes fails for some reason and retrying fixes it.
    local retry_count=0
    local gpg_ok="false"
    set +e
    until [ "${gpg_ok}" = "true" ] || [ "${retry_count}" -eq "5" ]; 
    do
        echo "(*) Downloading GPG key..."
        ( echo "${keys}" | xargs -n 1 gpg -q ${keyring_args} --recv-keys) 2>&1 && gpg_ok="true"
        if [ "${gpg_ok}" != "true" ]; then
            echo "(*) Failed getting key, retrying in 10s..."
            (( retry_count++ ))
            sleep 10s
        fi
    done
    set -e
    if [ "${gpg_ok}" = "false" ]; then
        echo "(!) Failed to get gpg key."
        exit 1
    fi
}

# Figure out correct version of a three part version number is not passed
find_version_from_git_tags() {
    local variable_name=$1
    local requested_version=${!variable_name}
    if [ "${requested_version}" = "none" ]; then return; fi
    local repository=$2
    local prefix=${3:-"tags/v"}
    local separator=${4:-"."}
    local last_part_optional=${5:-"false"}    
    if [ "$(echo "${requested_version}" | grep -o "." | wc -l)" != "2" ]; then
        local escaped_separator=${separator//./\\.}
        local last_part
        if [ "${last_part_optional}" = "true" ]; then
            last_part="(${escaped_separator}[0-9]+)?"
        else
            last_part="${escaped_separator}[0-9]+"
        fi
        local regex="${prefix}\\K[0-9]+${escaped_separator}[0-9]+${last_part}$"
        local version_list="$(git ls-remote --tags ${repository} | grep -oP "${regex}" | tr -d ' ' | tr "${separator}" "." | sort -rV)"
        if [ "${requested_version}" = "latest" ] || [ "${requested_version}" = "current" ] || [ "${requested_version}" = "lts" ]; then
            declare -g ${variable_name}="$(echo "${version_list}" | head -n 1)"
        else
            set +e
            declare -g ${variable_name}="$(echo "${version_list}" | grep -E -m 1 "^${requested_version//./\\.}([\\.\\s]|$)")"
            set -e
        fi
    fi
    if [ -z "${!variable_name}" ] || ! echo "${version_list}" | grep "^${!variable_name//./\\.}$" > /dev/null 2>&1; then
        echo -e "Invalid ${variable_name} value: ${requested_version}\nValid values:\n${version_list}" >&2
        exit 1
    fi
    echo "${variable_name}=${!variable_name}"
}

# Use semver logic to decrement a version number then look for the closest match
find_prev_version_from_git_tags() {
    local variable_name=$1
    local current_version=${!variable_name}
    local repository=$2
    # Normally a "v" is used before the version number, but support alternate cases
    local prefix=${3:-"tags/v"}
    # Some repositories use "_" instead of "." for version number part separation, support that
    local separator=${4:-"."}
    # Some tools release versions that omit the last digit (e.g. go)
    local last_part_optional=${5:-"false"}
    # Some repositories may have tags that include a suffix (e.g. actions/node-versions)
    local version_suffix_regex=$6
    # Try one break fix version number less if we get a failure. Use "set +e" since "set -e" can cause failures in valid scenarios.
    set +e
        major="$(echo "${current_version}" | grep -oE '^[0-9]+' || echo '')"
        minor="$(echo "${current_version}" | grep -oP '^[0-9]+\.\K[0-9]+' || echo '')"
        breakfix="$(echo "${current_version}" | grep -oP '^[0-9]+\.[0-9]+\.\K[0-9]+' 2>/dev/null || echo '')"

        if [ "${minor}" = "0" ] && [ "${breakfix}" = "0" ]; then
            ((major=major-1))
            declare -g ${variable_name}="${major}"
            # Look for latest version from previous major release
            find_version_from_git_tags "${variable_name}" "${repository}" "${prefix}" "${separator}" "${last_part_optional}"
        # Handle situations like Go's odd version pattern where "0" releases omit the last part
        elif [ "${breakfix}" = "" ] || [ "${breakfix}" = "0" ]; then
            ((minor=minor-1))
            declare -g ${variable_name}="${major}.${minor}"
            # Look for latest version from previous minor release
            find_version_from_git_tags "${variable_name}" "${repository}" "${prefix}" "${separator}" "${last_part_optional}"
        else
            ((breakfix=breakfix-1))
            if [ "${breakfix}" = "0" ] && [ "${last_part_optional}" = "true" ]; then
                declare -g ${variable_name}="${major}.${minor}"
            else 
                declare -g ${variable_name}="${major}.${minor}.${breakfix}"
            fi
        fi
    set -e
}

# Function to fetch the version released prior to the latest version
get_previous_version() {
    local url=$1
    local repo_url=$2
    local variable_name=$3
    local mode=$4
    prev_version=${!variable_name}
    
    output=$(curl -s "$repo_url");

    #install jq
    check_packages jq

    message=$(echo "$output" | jq -r '.message')

    if [[ $mode == "mode1" ]]; then
        message="API rate limit exceeded"
    else 
        message=""
    fi
    
    if [[ $message == "API rate limit exceeded"* ]]; then
        echo -e "\nAn attempt to find latest version using GitHub Api Failed... \nReason: ${message}"
        echo -e "\nAttempting to find latest version using GitHub tags."
        find_prev_version_from_git_tags prev_version "$url" "tags/v" "_"
        declare -g ${variable_name}="${prev_version}"
    else 
        echo -e "\nAttempting to find latest version using GitHub Api."
        version=$(echo "$output" | jq -r '.tag_name' | tr '_' '.')
        declare -g ${variable_name}="${version#v}"
    fi  
    echo "${variable_name}=${!variable_name}"
}

get_github_api_repo_url() {
    local url=$1
    echo "${url/https:\/\/github.com/https:\/\/api.github.com\/repos}/releases/latest"
}


# Figure out correct version of a three part version number is not passed
ruby_url="https://github.com/ruby/ruby"

RUBY_VERSION="3.4.xyz"

set_rvm_install_args() {
    RUBY_VERSION=$1
    if [ "${RUBY_VERSION}" = "none" ]; then
        RVM_INSTALL_ARGS=""
    elif [[ "$(ruby -v)" = *"${RUBY_VERSION}"* ]]; then
        echo "(!) Ruby is already installed with version ${RUBY_VERSION}. Skipping..."
        RVM_INSTALL_ARGS=""
    else
        if [ "${RUBY_VERSION}" = "latest" ] || [ "${RUBY_VERSION}" = "current" ] || [ "${RUBY_VERSION}" = "lts" ]; then
            RVM_INSTALL_ARGS="--ruby"
            RUBY_VERSION=""
        else
            RVM_INSTALL_ARGS="--ruby=${RUBY_VERSION}"
        fi
        if [ "${INSTALL_RUBY_TOOLS}" = "true" ]; then
            SKIP_GEM_INSTALL="true"
        else 
            DEFAULT_GEMS=""
        fi
    fi
}

install_previous_version() {
    mode=$1
    repo_url=$(get_github_api_repo_url "$ruby_url")
    get_previous_version "${ruby_url}" "${repo_url}" RUBY_VERSION $mode
    set_rvm_install_args $RUBY_VERSION
    curl -sSL https://get.rvm.io | bash -s stable --ignore-dotfiles ${RVM_INSTALL_ARGS} --with-default-gems="${DEFAULT_GEMS}" 2>&1
}

install_rvm() {
    mode=$1
    # Install RVM
    receive_gpg_keys RVM_GPG_KEYS
    # Determine appropriate settings for rvm installer
    set_rvm_install_args $RUBY_VERSION
    # Create rvm group as a system group to reduce the odds of conflict with local user UIDs
    if ! cat /etc/group | grep -e "^rvm:" > /dev/null 2>&1; then
        groupadd -r rvm
    fi
    # Install rvm
    curl -sSL https://get.rvm.io | bash -s stable --ignore-dotfiles ${RVM_INSTALL_ARGS} --with-default-gems="${DEFAULT_GEMS}" 2>&1 || install_previous_version "$mode"
    sudo usermod -aG rvm ${USERNAME}
    source /usr/local/rvm/scripts/rvm
    rvm fix-permissions system
    rm -rf ${GNUPGHOME}
}

install_rvm "mode1"
echo -e "\n👉🏻👉🏻RVM version installed by test file ... (mode: 1 - install using find_prev_version_from_git_tags):"
check "rvm" rvm --version

install_rvm "mode2"
echo -e "\n👉🏻👉🏻RVM version installed by test file ... (mode: 1 - install using GitHub Api):"
check "rvm" rvm --version

# Report result
reportResults