Directory.Build.props

<Project>
    <Import Project="$(MSBuildThisFileDirectory)Common.props" />

    <PropertyGroup>
        <!-- Attempt to read a .env file from the solution root -->
        <DotEnvFile>$(MSBuildThisFileDirectory).env</DotEnvFile>
    </PropertyGroup>

    <PropertyGroup Condition="Exists('$(DotEnvFile)')">
        <!-- Read file into a temporary property -->
        <_TempDotEnvContent>$([System.IO.File]::ReadAllText('$(DotEnvFile)'))</_TempDotEnvContent>

        <!-- Regex to find AVALONIA_LICENSE_KEY=value
             (?m) enables multiline mode so ^ matches start of line
             ^\s* matches start of line and optional whitespace
             \s*=\s* matches equals sign with optional whitespace around it
             ([^\s#]+) matches the value until whitespace or comment start -->
        <AvaloniaLicenseKeyPattern>(?m)^\s*AVALONIA_LICENSE_KEY\s*=\s*([^\s#]+)</AvaloniaLicenseKeyPattern>

        <!-- Extract key (an existing AVALONIA_LICENSE_KEY environment variable takes precedence) -->
        <AVALONIA_LICENSE_KEY Condition="'$(AVALONIA_LICENSE_KEY)' == ''">$([System.Text.RegularExpressions.Regex]::Match($(_TempDotEnvContent), $(AvaloniaLicenseKeyPattern)).Groups[1].Value)</AVALONIA_LICENSE_KEY>

        <!-- Clear the temporary property to prevent secrets from leaking into build logs -->
        <_TempDotEnvContent/>
    </PropertyGroup>
</Project>