$root = $PSScriptRoot
$out = "$root/public"
$staticDir = "$root/static"

$siteUrl = "https://nobleator.github.io"

$svgPath = "$root/assets/img/Hexaflake_Logo.svg"
$logoSvg = Get-Content -Raw -Path $svgPath
$navFile = "$root/nav.html"
$navHtml = @"
<header>
<a href='/' id='logo' alt='nobleator logo, links to homepage'$logoSvg</a>
<nav>
<a href='/'>Home</a>
<a href='/blog.html'>Blog</a>
<a href='/colophon.html'>Colophon</a>
<a href='/blogroll.html'>Blogroll</a>
</nav>
<button id='theme-toggle-button' onclick="toggleTheme()">Theme</button>
</header>
"@
$navHtml | Out-File $navFile -Encoding utf8

function Get-PostMeta($mdFile) {
    $json = pandoc $mdFile.FullName --template="$root/templates/metadata.json" -t html 2> $null # TeX rendering warnings will always emit here so ignoring
    $meta = $json | ConvertFrom-Json
    $meta | Add-Member -NotePropertyName BaseName -NotePropertyValue $mdFile.BaseName
    return $meta
}
function Convert-File($mdFile, $outFile) {
    pandoc $mdFile `
        --standalone `
        --template="$root/templates/page.html" `
        --include-before-body="$navFile" `
        --mathjax `
        -o $outFile
}

function Get-TagSlug($tag) {
    return ($tag.ToLower() -replace '[^a-z0-9]+', '-').Trim('-')
}

function Format-PostList($postMetas) {
    $links = $postMetas | ForEach-Object {
        $formattedDate = ([datetime]$_.date).ToString('yyyy-MM-dd')
        $tagLinks = (@($_.tags) | ForEach-Object {
            "<a href='/tags/$(Get-TagSlug $_).html' class='tag'>$_</a>"
        }) -join ' '
        "<li><span><i><time datetime='$formattedDate'>$formattedDate</time></i></span><a href='/posts/$($_.BaseName).html'>$($_.title)</a><span class='tags'>$tagLinks</span></li>"
    }
    return $links -join ''
}

function Format-RssItem($m) {
    $link = "$siteUrl/posts/$($m.BaseName).html"
    $postDate = [datetime]::SpecifyKind([datetime]$m.date, [DateTimeKind]::Utc)
    $pubDate = $postDate.ToString('R')
    $title = [System.Security.SecurityElement]::Escape($m.title)
    $desc = if ($m.description) { [System.Security.SecurityElement]::Escape($m.description) } else { $title }
    return @"
<item>
<title>$title</title>
<link>$link</link>
<guid isPermaLink='true'>$link</guid>
<pubDate>$pubDate</pubDate>
<description>$desc</description>
</item>
"@
}

function Get-GitLastModified($filePath) {
    $gitDate = git -C $root log -1 --format=%cd --date=short -- $filePath 2>$null
    if ([string]::IsNullOrWhiteSpace($gitDate)) {
        return (Get-Item $filePath).LastWriteTime.ToString('yyyy-MM-dd')
    }
    return $gitDate
}

if (Test-Path $out) {
    Get-ChildItem $out -Recurse | Remove-Item -Recurse -Force
} else {
    New-Item $out -ItemType Directory | Out-Null
}

Copy-Item "$root/assets" "$out/assets" -Recurse

$sitemapEntries = [System.Collections.Generic.List[string]]::new()
$today = (Get-Date).ToString('yyyy-MM-dd')
$sitemapEntries.Add("<url><loc>$siteUrl/</loc><lastmod>$today</lastmod></url>")

$pages = Get-ChildItem "$root/content/pages/*.md"

foreach ($p in $pages) {
    Convert-File $p.FullName "$out/$($p.BaseName).html"
    $lastmod = Get-GitLastModified $p.FullName
    $sitemapEntries.Add("<url><loc>$siteUrl/$($p.BaseName).html</loc><lastmod>$lastmod</lastmod></url>")
}

$posts = Get-ChildItem "$root/content/posts/*.md"
$metas = $posts | ForEach-Object { Get-PostMeta $_ }
$metas = $metas | Where-Object { $_.draft -ne "true" } | Sort-Object { [datetime]$_.date } -Descending

$postDates = @{}
foreach ($m in $metas) {
    $srcFile = Join-Path "$root/content/posts" "$($m.BaseName).md"
    Convert-File $srcFile "$out/posts/$($m.BaseName).html"
    $postDates[$m.BaseName] = Get-GitLastModified $srcFile
    $sitemapEntries.Add("<url><loc>$siteUrl/posts/$($m.BaseName).html</loc><lastmod>$($postDates[$m.BaseName])</lastmod></url>")
}

$allTags = $metas | ForEach-Object { @($_.tags) } | Where-Object { $_ } | Sort-Object -Unique

$tagCloud = ($allTags | ForEach-Object {
    "<a href='/tags/$(Get-TagSlug $_).html' class='tag'>$_</a>"
}) -join ' '

$blogMd = "# Posts`n`n<div class='tag-cloud'>$tagCloud</div>`n`n<ul class='blog-posts'>$(Format-PostList $metas)</ul>"
$blogMd | Out-File "$root/_blog_tmp.md" -Encoding utf8
Convert-File "$root/_blog_tmp.md" "$out/blog.html"
Remove-Item "$root/_blog_tmp.md"

$latestPostDate = if ($postDates.Count -gt 0) {
    ($postDates.Values | ForEach-Object { [datetime]$_ } | Sort-Object -Descending | Select-Object -First 1).ToString('yyyy-MM-dd')
} else {
    $today
}
$sitemapEntries.Add("<url><loc>$siteUrl/blog.html</loc><lastmod>$latestPostDate</lastmod></url>")

if (!(Test-Path "$out/tags")) {
    New-Item "$out/tags" -ItemType Directory | Out-Null
}

foreach ($tag in $allTags) {
    $slug = Get-TagSlug $tag
    $taggedMetas = $metas | Where-Object { @($_.tags) -contains $tag }
    $tagMd = "# Posts tagged '$tag'`n`n<ul class='blog-posts'>$(Format-PostList $taggedMetas)</ul>"
    $tagMd | Out-File "$root/_tag_tmp.md" -Encoding utf8
    Convert-File "$root/_tag_tmp.md" "$out/tags/$slug.html"
    Remove-Item "$root/_tag_tmp.md"
    $tagLatest = ($taggedMetas | ForEach-Object { [datetime]$postDates[$_.BaseName] } | Sort-Object -Descending | Select-Object -First 1).ToString('yyyy-MM-dd')
    $sitemapEntries.Add("<url><loc>$siteUrl/tags/$slug.html</loc><lastmod>$tagLatest</lastmod></url>")
}

Remove-Item $navFile

$sitemapXml = @"
<?xml version="1.0" encoding="UTF-8"?>
<urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">
$($sitemapEntries -join "`n")
</urlset>
"@
$sitemapXml | Out-File "$out/sitemap.xml" -Encoding utf8

$rssItems = ($metas | ForEach-Object { Format-RssItem $_ }) -join "`n"
$feedXml = @"
<?xml version="1.0" encoding="UTF-8"?>
<rss version="2.0">
<channel>
<title>nobleator</title>
<link>$siteUrl</link>
<description>nobleator's personal blog</description>
<lastBuildDate>$((Get-Date).ToUniversalTime().ToString('R'))</lastBuildDate>
<atom:link xmlns:atom="http://www.w3.org/2005/Atom" href="$siteUrl/feed.xml" rel="self" type="application/rss+xml" />
$rssItems
</channel>
</rss>
"@
$feedXml | Out-File "$out/feed.xml" -Encoding utf8

foreach ($f in @("robots.txt", "security.txt")) {
    $srcPath = Join-Path $staticDir $f
    if (Test-Path $srcPath) {
        Copy-Item $srcPath (Join-Path $out $f) -Force
    }
}

if (Test-Path "$out/security.txt") {
    New-Item "$out/.well-known" -ItemType Directory -Force | Out-Null
    Copy-Item "$out/security.txt" "$out/.well-known/security.txt" -Force
}

$root = $PSScriptRoot

Write-Host "Running fresh build..."
& "$root/build.ps1"

# start server in a background job, rooted in public/
$serverJob = Start-Job -ScriptBlock {
    param($dir)
    Set-Location $dir
    # python -m http.server 1313
    # You may need the following on macOS:
    python3 -m http.server 1313
} -ArgumentList "$root/public"

Write-Host "Server running at http://localhost:1313 (job id $($serverJob.Id))"

try {
    $watcher = New-Object System.IO.FileSystemWatcher
    $watcher.Path = "$root/content"
    $watcher.IncludeSubdirectories = $true
    $watcher.Filter = "*.md"

    Write-Host "Watching for changes... Ctrl+C to stop."
    while ($true) {
        $result = $watcher.WaitForChanged([System.IO.WatcherChangeTypes]::All, 1000)
        if ($result.TimedOut) { continue }
        Write-Host "Change detected: $($result.Name) - rebuilding..."
        & "$root/build.ps1"
    }
}
finally {
    Stop-Job $serverJob
    Remove-Job $serverJob
}

param([string]$additionalMessage) 

"Deploying updates for GitHub pages site"
$currentDirectory = Get-Location
$today = Get-Date
$message = "Rebuilding site and publishing on $today"
if ($additionalMessage) {
    $message = $message + ": " + $additionalMessage
}

$root = $PSScriptRoot
Write-Host "Running fresh build..."
& "$root/build.ps1"

"Copying files from .\public into ..\nobleator.github.io"
if (-Not (Test-Path ..\nobleator.github.io)) {
    throw "..\nobleator.github.io must exist relative to this script!"
}

Copy-Item -Path .\public\* -Destination ..\nobleator.github.io -Recurse -Force

"Navigating to ..\nobleator.github.io"
Set-Location ..\nobleator.github.io
"Adding changes"
git add .
"Committing changes"
git commit -m "$message"
"Pushing changes to master"
git push origin master
"Navigating to ${currentDirectory}"
Set-Location $currentDirectory

"Deployment complete"