#!/usr/bin/env bash

set -euo pipefail
IFS=$'\n\t'

# This file can only be sourced, not executed directly.
if [[ "${BASH_SOURCE[0]}" == "${0}" ]]; then
    echo "This script is intended to be sourced, not executed directly." >&2
    exit 1
fi

function validate_version_format() {
    local v="$1"
    [[ "$v" =~ ^v?[0-9]+\.[0-9]+\.[0-9]+$ ]]
}

function get_latest_version() {
    local json version
    json="$(curl -fsSL https://api.github.com/repos/Psiphon-Labs/psiphon-tunnel-core/releases/latest)"
    if command -v jq >/dev/null 2>&1; then
        version="$(printf '%s' "$json" | jq -r .tag_name)"
    else
        version="$(printf '%s' "$json" \
            | grep -m1 '"tag_name":' \
            | sed -E 's/.*"tag_name": ?"([^"]+)".*/\1/')"
    fi

    if ! validate_version_format "$version"; then
        echo "I tried to get the latest version of Psiphon without jq but it didn't work." >&2 
        echo "Please install jq or specify the version manually." >&2
        exit 1
    fi

    printf '%s\n' "$version"
}

function normalize_version() {
    local v="$1"
    if [[ "$v" =~ ^v ]]; then
        echo "$v"
    else
        echo "v$v"
    fi
}