param(
    [string]$Root = (Split-Path -Parent $PSScriptRoot)
)

$ErrorActionPreference = 'Stop'
$failures = [System.Collections.Generic.List[string]]::new()
$warnings = [System.Collections.Generic.List[string]]::new()

$targetsDir = Join-Path $Root 'targets'
$targetIndex = Join-Path $targetsDir 'README.md'
$targetFiles = Get-ChildItem -LiteralPath $targetsDir -File |
    Where-Object { $_.Name -match '^\d\d-.*\.md$' } |
    Sort-Object Name

$activeTargets = [System.Collections.Generic.List[object]]::new()
$statusPattern = '<!-- OPENWC_TARGET:(OPEN|ACTIVE|BLOCKED|DONE) -->'

foreach ($file in $targetFiles) {
    $content = Get-Content -Raw -Encoding UTF8 -LiteralPath $file.FullName
    $matches = [regex]::Matches($content, $statusPattern)
    if ($matches.Count -ne 1) {
        $failures.Add("$($file.Name): expected exactly one target status marker, found $($matches.Count)")
        continue
    }
    if ($matches[0].Groups[1].Value -eq 'ACTIVE') {
        $activeTargets.Add($file)
    }
}

if ($activeTargets.Count -ne 1) {
    $failures.Add("Expected exactly one ACTIVE target, found $($activeTargets.Count)")
}

if (-not (Test-Path -LiteralPath $targetIndex)) {
    $failures.Add('targets/README.md is missing')
} else {
    $indexContent = Get-Content -Raw -Encoding UTF8 -LiteralPath $targetIndex
    $currentMatch = [regex]::Match($indexContent, '(?s)## Current target\s+`(M\d\d)`[^\r\n]*\[[^\]]+\]\(([^)]+)\)')
    if (-not $currentMatch.Success) {
        $failures.Add('Could not parse Current target from targets/README.md')
    } elseif ($activeTargets.Count -eq 1) {
        $expectedId = $currentMatch.Groups[1].Value
        $expectedFile = $currentMatch.Groups[2].Value
        $activeFile = $activeTargets[0].Name
        $activeId = 'M' + $activeFile.Substring(0, 2)
        if ($expectedId -ne $activeId -or $expectedFile -ne $activeFile) {
            $failures.Add("Current target points to $expectedId/$expectedFile but ACTIVE is $activeId/$activeFile")
        }
    }
}

$claimsDir = Join-Path $Root 'coordination\claims'
$claimIds = @{}
$claimPattern = '<!-- OPENWC_CLAIM:([A-Z0-9-]+):([a-z0-9-]+):(\d{4}-\d{2}-\d{2}) -->'

if (Test-Path -LiteralPath $claimsDir) {
    $claimFiles = Get-ChildItem -LiteralPath $claimsDir -Filter '*.md' -File |
        Where-Object { $_.Name -ne 'README.md' }
    foreach ($file in $claimFiles) {
        $content = Get-Content -Raw -Encoding UTF8 -LiteralPath $file.FullName
        $matches = [regex]::Matches($content, $claimPattern)
        if ($matches.Count -ne 1) {
            $failures.Add("coordination/claims/$($file.Name): expected exactly one valid OPENWC_CLAIM marker")
            continue
        }
        $claimId = $matches[0].Groups[1].Value
        if ($claimIds.ContainsKey($claimId)) {
            $failures.Add("Duplicate claim ID $claimId in $($claimIds[$claimId]) and $($file.Name)")
        } else {
            $claimIds[$claimId] = $file.Name
        }
        $expiryText = $matches[0].Groups[3].Value
        $expiry = [datetime]::ParseExact($expiryText, 'yyyy-MM-dd', [Globalization.CultureInfo]::InvariantCulture)
        if ($expiry.Date -lt (Get-Date).ToUniversalTime().Date) {
            $warnings.Add("Claim $claimId expired on $expiryText")
        }
    }
}

foreach ($warning in $warnings) {
    Write-Warning $warning
}

if ($failures.Count -gt 0) {
    foreach ($failure in $failures) {
        Write-Error $failure
    }
    exit 1
}

Write-Output "Coordination check passed: targets=$($targetFiles.Count) active=$($activeTargets.Count) fallback_claims=$($claimIds.Count) warnings=$($warnings.Count)"
exit 0