# During session initialization
$prNumber = 669
$branch = git branch --show-current

# Update Serena memory
Update-PRBranchMapping -PRNumber $prNumber -Branch $branch -SessionId "session-110"

# Pre-commit hook queries mapping
$currentBranch = git branch --show-current
$expectedPR = Get-PRForBranch -Branch $currentBranch

if ($env:SESSION_PR -and $env:SESSION_PR -ne $expectedPR) {
    Write-Error "Branch/PR mismatch: expected PR $expectedPR, session context shows PR $env:SESSION_PR"
    exit 1
}

function Add-PRBranchMapping {
    param(
        [int]$PRNumber,
        [string]$BranchName,
        [string]$SessionId
    )
    
    # Read current mapping from Serena
    $mapping = Read-SerenaMemory -Name "pr-branch-mapping"
    
    # Add/update entry
    $mapping.mappings += @{
        pr_number = $PRNumber
        branch_name = $BranchName
        created_at = (Get-Date).ToUniversalTime().ToString("o")
        last_session = $SessionId
    }
    
    # Update current session
    $mapping.current_session = @{
        session_id = $SessionId
        pr_number = $PRNumber
        branch_name = $BranchName
    }
    
    # Write back to Serena
    Write-SerenaMemory -Name "pr-branch-mapping" -Content $mapping
}

function Get-PRForBranch {
    param([string]$BranchName)
    
    $mapping = Read-SerenaMemory -Name "pr-branch-mapping"
    $entry = $mapping.mappings | Where-Object { $_.branch_name -eq $BranchName } | Select-Object -First 1
    
    return $entry.pr_number
}

function Test-BranchPRConsistency {
    $currentBranch = git branch --show-current
    $mapping = Read-SerenaMemory -Name "pr-branch-mapping"
    
    if ($mapping.current_session.branch_name -ne $currentBranch) {
        Write-Warning "Branch mismatch: current=$currentBranch, expected=$($mapping.current_session.branch_name)"
        return $false
    }
    
    return $true
}