# Python bootstrap shared by the Windows launcher and its isolated checks.
# Keep this file ASCII for Windows PowerShell 5.1.

function Initialize-ArtemisPython {
    param([Parameter(Mandatory=$true)][string]$ProjectRoot)

    $ProjectRoot = (Resolve-Path -LiteralPath $ProjectRoot -ErrorAction Stop).Path
    if (-not (Test-Path -LiteralPath (Join-Path $ProjectRoot 'pyproject.toml'))) {
        throw 'pyproject.toml is missing. Extract the complete source archive first.'
    }
    if (-not (Test-Path -LiteralPath (Join-Path $ProjectRoot 'uv.lock'))) {
        throw 'uv.lock is missing. Extract the complete source archive first.'
    }

    if (-not (Test-CommandExists 'uv')) {
        if ($ArtemisDownloads -and $ArtemisDownloads.python_index) {
            Write-Host '   [INSTALL] Installing uv from the selected Python mirror...' -ForegroundColor Cyan
            Install-ArtemisUvFromIndex -IndexUrl $ArtemisDownloads.python_index
        } else {
            Write-Host '   [INSTALL] uv was not found. Installing from the configured installer...' -ForegroundColor Cyan
            $installer = Join-Path ([IO.Path]::GetTempPath()) ('artemis-uv-' + [guid]::NewGuid().ToString('N') + '.ps1')
            try {
                $installerUrl = if ($ArtemisDownloads) { $ArtemisDownloads.uv_installer_url } else { 'https://astral.sh/uv/install.ps1' }
                if (-not (Invoke-DownloadFile -Uri $installerUrl -OutFile $installer)) {
                    throw 'Could not download uv. Check your network/proxy and retry.'
                }
                & powershell.exe -NoProfile -ExecutionPolicy Bypass -File $installer | Out-Host
                if ($LASTEXITCODE -ne 0) { throw "uv installation failed (exit $LASTEXITCODE)." }
            } finally {
                Remove-Item -LiteralPath $installer -Force -ErrorAction SilentlyContinue
            }
        }
        Update-EnvironmentPath
    } else {
        Write-Host '   [SKIP] uv is already installed.' -ForegroundColor Green
    }
    if (-not (Test-CommandExists 'uv')) { throw 'uv is still unavailable. Install it from https://astral.sh/uv/ and retry.' }
    & uv --version | Out-Host
    if ($LASTEXITCODE -ne 0) { throw 'The installed uv could not run. Repair its installation and retry.' }

    $venvDir = Join-Path $ProjectRoot '.venv'
    $pythonExe = Join-Path $venvDir 'Scripts\python.exe'
    $previousEnvironment = $env:UV_PROJECT_ENVIRONMENT
    $env:UV_PROJECT_ENVIRONMENT = $venvDir
    Push-Location -LiteralPath $ProjectRoot
    try {
        if (-not (Test-Path -LiteralPath $venvDir)) {
            Write-Host '   [INSTALL] Creating .venv with Python 3.12 (downloaded automatically if needed)...' -ForegroundColor Cyan
            & uv venv --python 3.12 $venvDir | Out-Host
            if ($LASTEXITCODE -ne 0) { throw 'Could not create .venv. Check the download errors above and retry.' }
        } else {
            Write-Host '   [SKIP] Reusing the existing project .venv.' -ForegroundColor Green
        }
        if (-not (Test-Path -LiteralPath $pythonExe)) {
            throw 'The existing .venv is incomplete. Rename it as a backup, then rerun start.bat.'
        }
        & $pythonExe -c 'import sys; sys.exit(0 if sys.version_info >= (3, 12) and sys.prefix != sys.base_prefix else 1)' | Out-Host
        if ($LASTEXITCODE -ne 0) {
            throw 'The existing .venv is unusable or older than Python 3.12. Rename it as a backup, then rerun start.bat.'
        }

        # A cheap check skips installation when the lock and installed packages agree.
        # --inexact preserves any optional development tools already installed.
        $lockOption = if ($ArtemisDownloads -and $ArtemisDownloads.python_index) { '--frozen' } else { '--locked' }
        & uv sync --check $lockOption --no-dev --inexact --quiet 2>$null | Out-Host
        if ($LASTEXITCODE -eq 0) {
            Write-Host '   [SKIP] Python dependencies are already ready.' -ForegroundColor Green
        } else {
            Write-Host '   [INSTALL] Synchronizing dependencies from uv.lock...' -ForegroundColor Cyan
            if ($ArtemisDownloads -and $ArtemisDownloads.python_index) {
                Install-ArtemisLockedDependencies -PythonExe $pythonExe -IndexUrl $ArtemisDownloads.python_index
            } else {
                & uv sync --locked --no-dev --inexact | Out-Host
                if ($LASTEXITCODE -ne 0) { throw 'Dependency installation failed. Fix the error above and rerun start.bat.' }
            }
        }
        & $pythonExe -c 'import artemis, uvicorn, fastapi, langchain_openai' | Out-Host
        if ($LASTEXITCODE -ne 0) { throw 'Python dependency verification failed. The UI will not be started.' }
        Write-Host '   [OK] Python environment is ready.' -ForegroundColor Green
        return $pythonExe
    } finally {
        Pop-Location
        $env:UV_PROJECT_ENVIRONMENT = $previousEnvironment
    }
}