# hooks/archive-check.ps1
# Check changed .md files and suggest related docs to update.
# This script only outputs suggestions; it does NOT modify any files.
#
# Mechanism:
#   For every changed .md file, parse its "## 文档关联" section and extract
#   Markdown links. Those links are the documents that may need syncing.

$ErrorActionPreference = "SilentlyContinue"

$scriptPath = $MyInvocation.MyCommand.Path
if (-not [System.IO.Path]::IsPathRooted($scriptPath)) {
    $scriptPath = Join-Path (Get-Location) $scriptPath
}
$scriptPath = [System.IO.Path]::GetFullPath($scriptPath)
$scriptDir = Split-Path -Parent $scriptPath
$projectRoot = [System.IO.Path]::GetFullPath((Join-Path $scriptDir ".."))

Set-Location $projectRoot

# ---------------------------------------------------------------------------
# Helpers
# ---------------------------------------------------------------------------

function Resolve-RelativePath {
    param(
        [string]$BaseFile,
        [string]$LinkPath
    )

    # Skip anchors, query strings, and external URLs
    if ($LinkPath -match '^[a-zA-Z][a-zA-Z0-9+.-]*://') { return $null }
    if ([string]::IsNullOrWhiteSpace($LinkPath)) { return $null }

    # Drop fragment
    $pathOnly = ($LinkPath -split '#')[0]
    if ([string]::IsNullOrWhiteSpace($pathOnly)) { return $null }

    $baseDir = Split-Path -Parent $BaseFile
    $combined = Join-Path $baseDir $pathOnly
    try {
        $resolved = [System.IO.Path]::GetFullPath($combined)
    } catch {
        return $null
    }

    # Convert to relative path from project root, normalizing separators
    $fullProjectRoot = [System.IO.Path]::GetFullPath($projectRoot)
    if ($resolved.StartsWith($fullProjectRoot, [System.StringComparison]::OrdinalIgnoreCase)) {
        $relative = $resolved.Substring($fullProjectRoot.Length).TrimStart('\', '/')
        return $relative -replace '\\', '/'
    }
    return $pathOnly -replace '\\', '/'
}

function Get-DocumentAssociations {
    param(
        [string]$MdFile
    )

    $fullPath = Join-Path $projectRoot $MdFile
    if (-not (Test-Path $fullPath)) { return @() }

    $lines = [System.IO.File]::ReadAllLines($fullPath, [System.Text.Encoding]::UTF8)
    $associations = @()
    $inSection = $false
    $inCodeBlock = $false

    foreach ($line in $lines) {
        # Toggle fenced code block state (``` or ~~~)
        if ($line -match '^\s*```' -or $line -match '^\s*~~~') {
            $inCodeBlock = -not $inCodeBlock
            continue
        }
        if ($inCodeBlock) { continue }

        # Match exactly '## 文档关联' (not '## 文档关联机制' etc.).
        if ($line -match "^##\s+文档关联\s*$") {
            $inSection = $true
            continue
        }
        if ($inSection -and $line -match '^##\s+') {
            break
        }
        if ($inSection) {
            # Extract markdown links: [text](path)
            $regex = '\[(?<text>[^\]]*)\]\((?<path>[^\)]+)\)'
            $matches = [regex]::Matches($line, $regex)
            foreach ($match in $matches) {
                $linkPath = $match.Groups['path'].Value.Trim()
                $resolved = Resolve-RelativePath -BaseFile $MdFile -LinkPath $linkPath
                if ($resolved) {
                    $associations += $resolved
                }
            }
        }
    }

    return $associations | Select-Object -Unique
}

function Test-WildcardMatch {
    param(
        [string]$Pattern,
        [string]$Path
    )
    $regex = "^" + ($Pattern -replace "\.", "\." -replace "\*", ".*" -replace "\?", ".") + "$"
    return $Path -match $regex
}

# ---------------------------------------------------------------------------
# Collect changed .md files (tracked modifications + untracked new files)
# ---------------------------------------------------------------------------

$changedFiles = @(cmd /c "git diff --name-only 2>nul") | Where-Object { $_ }
if ($changedFiles.Count -eq 0) {
    $changedFiles = @(cmd /c "git diff --name-only --cached 2>nul") | Where-Object { $_ }
}

# Also include untracked .md files so new documents are checked too
$untrackedFiles = @(cmd /c "git ls-files --others --exclude-standard 2>nul") | Where-Object { $_ }
$allChangedFiles = @($changedFiles) + @($untrackedFiles) | Where-Object { $_ } | Select-Object -Unique

if (-not $allChangedFiles) {
    Write-Output "[archive-check] No documentation changes detected (git diff is empty and no untracked .md files)."
    exit 0
}

$changedMdFiles = $allChangedFiles | Where-Object { $_ -like "*.md" } | Select-Object -Unique

if ($changedMdFiles.Count -eq 0) {
    Write-Output "[archive-check] No .md documentation changes detected."
    exit 0
}

# ---------------------------------------------------------------------------
# Build suggestions from each changed file's "## 文档关联" section
# ---------------------------------------------------------------------------

$suggestions = @{}

foreach ($changed in $changedMdFiles) {
    $relatedDocs = Get-DocumentAssociations -MdFile $changed
    foreach ($related in $relatedDocs) {
        # Normalize related path
        $relatedNormalized = $related -replace '\\', '/'
        if (-not $suggestions.ContainsKey($relatedNormalized)) {
            $suggestions[$relatedNormalized] = @()
        }
        if ($suggestions[$relatedNormalized] -notcontains $changed) {
            $suggestions[$relatedNormalized] += $changed
        }
    }
}

# ---------------------------------------------------------------------------
# Output results
# ---------------------------------------------------------------------------

Write-Output "[archive-check] Changed documentation files:"
foreach ($changed in $changedMdFiles | Sort-Object) {
    Write-Output "  - $changed"
}

if ($suggestions.Count -eq 0) {
    Write-Output ""
    Write-Output "[archive-check] No associations found in changed files' `"## 文档关联`" sections."
    exit 0
}

Write-Output ""
Write-Output "[archive-check] Related docs that may need updating:"
foreach ($related in $suggestions.Keys | Sort-Object) {
    $sources = $suggestions[$related] | Sort-Object
    $sourceList = $sources -join ", "
    Write-Output "  - $related (mentioned by: $sourceList)"
}

Write-Output ""
Write-Output "[archive-check] Please confirm whether to sync-update the above docs."
exit 0