# PowerShell Lint Script for LLM Knowledge Base
# This script scans the knowledge/ directory for broken WikiLinks, orphan pages, and unlinked concepts/entities.

$knowledgeDir = Resolve-Path "knowledge"
$files = Get-ChildItem -Path $knowledgeDir -Recurse -Filter *.md

# Maps to keep track of files and links
$existingFiles = @{} # file name/path -> absolute path
$fileIncomingLinks = @{} # relative path -> list of incoming files

# Exclude list for orphan check (master files)
$excludeOrphans = @(
    "knowledge\index.md",
    "knowledge\log.md",
    "knowledge\feynman_problems.md"
)

# Initialize files
foreach ($file in $files) {
    # Normalize relative path (e.g. "knowledge/concepts/accidental-dba.md")
    $relPath = (Resolve-Path $file.FullName -Relative) -replace "^\.\\", "" -replace "\\", "/"
    $existingFiles[$relPath] = $file.FullName
    
    # Also index by base name (without extension) for simple links, e.g. [[log]] -> "knowledge/log.md"
    $baseName = [System.IO.Path]::GetFileNameWithoutExtension($file.Name)
    $existingFiles[$baseName] = $file.FullName
    $existingFiles[$relPath -replace "\.md$", ""] = $file.FullName
    
    # Initialize incoming links list
    $fileIncomingLinks[$relPath] = [System.Collections.Generic.List[string]]::new()
}

$brokenLinks = [System.Collections.Generic.List[PSCustomObject]]::new()

# Scan each file for links
foreach ($file in $files) {
    $relPath = (Resolve-Path $file.FullName -Relative) -replace "^\.\\", "" -replace "\\", "/"
    $content = Get-Content -Path $file.FullName -Raw
    
    # Match [[WikiLinks]] (can include aliases, e.g. [[link|alias]] or [[link]])
    # Regex matches anything inside [[ and ]] except newlines or brackets
    $matches = [regex]::Matches($content, "\[\[([^\]|]+)(?:\|[^\]]*)?\]\]")
    
    foreach ($m in $matches) {
        $linkTarget = $m.Groups[1].Value.Trim()
        
        # Normalize target path
        # Try resolving directly, with .md, or prefixing with "knowledge/"
        $resolvedPath = $null
        
        $candidates = @(
            $linkTarget,
            "$linkTarget.md",
            "knowledge/$linkTarget",
            "knowledge/$linkTarget.md"
        )
        
        foreach ($c in $candidates) {
            $normalizedC = $c -replace "\\", "/"
            if ($existingFiles.ContainsKey($normalizedC)) {
                $resolvedPath = $existingFiles[$normalizedC]
                break
            }
        }
        
        if ($resolvedPath) {
            # Link is valid! Log incoming link
            $resolvedRelPath = (Resolve-Path $resolvedPath -Relative) -replace "^\.\\", "" -replace "\\", "/"
            if ($resolvedRelPath -ne $relPath) { # ignore self-links
                $fileIncomingLinks[$resolvedRelPath].Add($relPath)
            }
        } else {
            # Link is broken!
            $brokenLinks.Add([PSCustomObject]@{
                SourceFile = $relPath
                LinkTarget = $linkTarget
                MatchText  = $m.Value
            })
        }
    }
}

# Find Orphans
$orphans = [System.Collections.Generic.List[string]]::new()
foreach ($key in $fileIncomingLinks.Keys) {
    # Check if file is in exclude orphans list
    $isExcluded = $false
    foreach ($ex in $excludeOrphans) {
        $normalizedEx = $ex -replace "\\", "/"
        if ($key -eq $normalizedEx -or $key -like "knowledge/indices/*") {
            $isExcluded = $true
            break
        }
    }
    
    # An orphan is a file that is not master index/indices and has 0 incoming links (except from index files themselves)
    if (-not $isExcluded) {
        $incoming = $fileIncomingLinks[$key]
        
        # Filter out incoming links that are indices or master index
        $realIncomingCount = 0
        foreach ($inc in $incoming) {
            if ($inc -ne "knowledge/index.md" -and $inc -notlike "knowledge/indices/*") {
                $realIncomingCount++
            }
        }
        
        if ($realIncomingCount -eq 0) {
            $orphans.Add($key)
        }
    }
}

# Print Beautiful Report
Write-Host "==========================================" -ForegroundColor Green
Write-Host "      KNOWLEDGE BASE LINT REPORT" -ForegroundColor Green
Write-Host "==========================================" -ForegroundColor Green
Write-Host "Total Files Scanned: $($files.Count)" -ForegroundColor Cyan
Write-Host ""

if ($brokenLinks.Count -eq 0) {
    Write-Host "[OK] No broken WikiLinks found!" -ForegroundColor Green
} else {
    Write-Host "[WARNING] Found $($brokenLinks.Count) broken WikiLink(s):" -ForegroundColor Yellow
    foreach ($bl in $brokenLinks) {
        Write-Host "  - In '$($bl.SourceFile)': Link '$($bl.LinkTarget)' is broken (Match: '$($bl.MatchText)')" -ForegroundColor Red
    }
}
Write-Host ""

if ($orphans.Count -eq 0) {
    Write-Host "[OK] No orphan pages found!" -ForegroundColor Green
} else {
    Write-Host "[INFO] Found $($orphans.Count) orphan page(s) (no incoming links from other content pages):" -ForegroundColor Yellow
    foreach ($o in $orphans) {
        Write-Host "  - $o" -ForegroundColor DarkYellow
    }
}
Write-Host ""
Write-Host "Lint completed successfully." -ForegroundColor Green