param(
	$Url,
	$CookiesFromBrowser = "firefox"
)

while (1) {
	<# get format info #>
	while (1) {
		Write-Host "Checking if stream is live..."
		$x = yt-dlp --cookies-from-browser $CookiesFromBrowser -F $Url
		if ($LASTEXITCODE -eq 0) {
			write-warning "Live!"
			break;
		}
		Write-Warning "Not live, waiting 5 minutes >> $ww"
		sleep (60*5)
	}

	Write-Host "Ripping formats with yt-dlp..."
	$InfoJson = yt-dlp --cookies-from-browser $CookiesFromBrowser --dump-json $Url | ConvertFrom-Json
	$VideoId = $InfoJson.id
	$DvrVideoFmt = $InfoJson.formats | ? { $_.format_id -ilike "*dvr*" } | select-object -last 1
	$DvrAudioFmts = $InfoJson.formats | ? { $_.format_id -ilike "*dvr*audio*" }

	# TODO: DVR video format may sometimes also carry audio with it, take into account vvv

	if (( $DvrAudioFmts | ? { $_.format_id -ilike '*bypass*' } )) {
		$DvrAudioFmt = $DvrAudioFmts | ? { $_.format_id -ilike '*bypass*' } | select-object -last 1
	} else {
		$DvrAudioFmt = $DvrAudioFmts | select-object -last 1
		Write-Warning "DVR bypass audio format not available. Using potentially lower quality $($DvrAudioFmt.format_id) format!"
	}
	
	if ($null -eq $DvrVideoFmt) {
		Write-Warning "The DVR video format isn't available yet/anymore. Cannot proceed!!! Is the stream live?"
		exit 1
	} elseif ($null -eq $DvrAudioFmt) {
		Write-Warning "The DVR video format isn't available yet/anymore. Cannot proceed!!! Is the stream live?"
		exit 1
	}

	break;
}

Write-Host "Selected formats (v)$($DvrVideoFmt.format_id) + (a)$($DvrAudioFmt.format_id)"

<# ### ### ### #>

$Headers = @{
	'User-Agent' = 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/143.0.0.0 Safari/537.36'
	'Accept' = 'text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8'
	'Accept-Language' = 'en-us,en;q=0.5'
	'Sec-Fetch-Mode' = 'navigate'
	'Referer' = 'https://www.openrec.tv/'
}

$BinFiles = (("v@"+$DvrVideoFmt.format_id), $DvrVideoFmt),(("a@"+$DvrAudioFmt.format_id), $DvrAudioFmt) | % -Throttle 2 -Parallel {
	$Hs = $using:Headers

	$existing = [System.Collections.Concurrent.ConcurrentBag[Int32]]::new()
	
	$VideoId = $using:VideoId
	$ThreadId = $_[0]
	$Fmt = $_[1]
	$Id = $Fmt.format_id
	$Playlist = $Fmt.url
	$LocalPlaylistFile = "$VideoId--$Id.m3u8"
	$FragUrlBase = $Playlist -replace 'chunklist(_\d.*|\.m3u8)',''
	
	function l([Switch]$D, [Switch]$W,[Switch]$E, $Message) {
		if ($E) {
			throw "[$ThreadId]: $Message"
		} elseif ($W) {
			Write-Host "[$ThreadId]: $Message" -Foreground Yellow
		} elseif ($D) {
			Write-Host "[$ThreadId]: $Message" -Foreground DarkGray
		} else {
			Write-Host "[$ThreadId]: $Message"
		}
	}

	# like 0/seg_<some id?>_<FRAGNO>_<video|audio>_<timestamp?>_llhls.m4s
	filter parse-fragmentname() {
		if ($_ -like "*.m4s") {
			$_ -match '(?<=0\/seg_\d_)\d+' | out-null
		} else {
			$_ -match '\d+(?=\.(?:ts|aac)$)' |out-null
		}
		
		$FragLinkName = $_ -split '/',2 | select-object -last 1
		$raw = $matches[0]
		
		return @{ Link=$_; Id=[int]::parse($Raw); Filename=$FragLinkName }
	}

	try {
		l "reading $VideoId--$ThreadId.finished"
		$PreexistingFragments = gc "$VideoId--$ThreadId.finished" -ea stop
		l "found $( $PreexistingFragments.Count ) preexisting fragments, skipping them..."
		$PreexistingFragments | % { $existing.Add( [int]::parse($_) ) }
	} catch {
		l "found no preexisting fragments"
		# first run, dont worry
	}

	l "hello for list $Playlist"

	new-item -type dir -name "$VideoId--$Id" -force | out-null
	
	$StreamHasEnded = $false
	#$StreamHasEnded = $true # true for testing

	<# initial playlist download #>
	try {
		if (-not $StreamHasEnded) {
			iwr -Headers $Hs $Playlist -Outfile $LocalPlaylistFile -SessionVar Session
		} else {
			# testing as mentioned still needs $session which is also now made here
			iwr -Headers $Hs $using:Url -SessionVar Session | Out-Null
		}
	} catch {
		l -E "Failed to get playlist $Playlist. Cannot proceed!"
	}
	
	<# SOME playlists are m4s, some are aac+ts #>
	$Filetype = (gc $LocalPlaylistFile | select-object -first 20 | ? { $_ -notmatch '^#' } | select-object -first 1) -split '\.' | select-object -last 1
	if ($Filetype -eq 'm4s') {
		<# get m4s init fragment #>	
		$InitFrag = (gc $LocalPlaylistFile | select-object -first 20 | ? { $_ -like '#EXT-X-MAP:URI=*' } ) -split '=',2 -replace '^.|.$','' | select-object -last 1
		$InitFragName = $InitFrag -replace '^0\/',''
		l "Found M4S, init=$InitFragName"
		try {
			iwr -WebSession $Session "$FragUrlBase$InitFrag" -OutFile "$VideoId--$Id/a-$InitFragName"
		} catch {
			l -E "Failed to get init fragment, cannot proceed!!!"
		}
	} else {
		# no init for aac+ts formats
		l "Found $Filetype"
	}
	
	<# loop and download fragments #>
	$NoNewFragmentRoundAttemptsRemaining = 10
	while (1) {
		if (-not $StreamHasEnded) {
			<# if playlist fails, retry a few times in case of network issues #>
			$refreshes = 10
			while ( $refreshes -gt 0) {
				try {
					l -D "Refreshing playlist... ($refreshes attempts remaining)"
					iwr -WebSession $Session $Playlist -Outfile $LocalPlaylistFile
					break;
				} catch {
					$refreshes--
					sleep 6
					# no continue, fall through to next if() when <=0
				}
			}

			if ($refreshes -le 0) {
				l -W "Failed to refresh playlist 10 times, assuming stream has ended"
				$StreamHasEnded = $true
				continue;
			}

			if ( (gc $LocalPlaylistFile -Raw) -like "*#EXT-X-ENDLIST*") {
				l -W "Found EXT-X-ENDLIST marker in playlist; stream has ended!"
				$StreamHasEnded = $true	
				continue;
			}
		}
		
		$AllFragments = get-content $LocalPlaylistFile | ? { $_ -notmatch '^#' }

		<# filter out what we already have #>
		$PendingFragments = $AllFragments | parse-fragmentname | ? { $_.Id -notin $existing }
		# pending will unexpectedly be a hashtable instead of hashtable[] when the ? clause returns only one element
		if ( $null -ne $PendingFragments -and $PendingFragments.GetType() -eq [Hashtable] ) {
			$PendingFragments = @($PendingFragments)
		}
		
		$s = (2 + (get-random -min -1.0 -max 1.0))

		<# check if playlist has stagnated, on 10 straight refreshes and stagnations (60s), break #>
		if ($null -eq $PendingFragments) {
			if (-not $StreamHasEnded) {
				if ($NoNewFragmentRoundAttemptsRemaining -le 0) {
					l -W "No new fragments found in the last 10 rounds! Assuming the stream has ended..."
					$StreamHasEnded = $true
					continue;
				}
			
				$NoNewFragmentRoundAttemptsRemaining--
				l -W "No new fragments! $NoNewFragmentRoundAttemptsRemaining attempts remaining..."
				l -D "playlist: sleeping $s"
				sleep 6
				continue;
			} else {
				l "No new fragments and the stream has been marked as over. Exiting thread, post-processing will continue after both threads exit."
				break;
			}
		}
		
		<# found some fragments... #>
		l "Found $( $PendingFragments.Count ) new fragments: $( ($PendingFragments.Id) -join ',' )"
		# ok this can actually be pretty small, the website hits its playlist like every 2 seconds
		# smaller = refresh playlist sooner, less chance of missing some fragnents at the end
		$FragmentAmount = 6 

		$PendingFragments = $PendingFragments | Select-Object -first $FragmentAmount
		l "Selecting earliest $( [math]::min($FragmentAmount, $PendingFragments.Count) ) fragments to run: $( ($PendingFragments.Id) -join ',' )"

		<# no new fragments? #>
		if ($PendingFragments.Count -eq 0) {
			if ($NoNewFragmentRoundAttemptsRemaining -le 0) {
				l -W "No new fragments found in the last 10 rounds! Assuming the stream has ended..."
				$StreamHasEnded = $true
				continue;
			}
			
			$NoNewFragmentRoundAttemptsRemaining--
			l -W "No new fragments! $NoNewFragmentRoundAttemptsRemaining attempts remaining"
			l -D "playlist: sleeping $s"
			sleep ($s*2)
			continue;
		}
		$NoNewFragmentRoundAttemptsRemaining = 10

		<# download new fragments #>
		$PendingFragments | % -throttle ($FragmentAmount/2) -par {
			$FragmentData = $_
			$ThreadId = $using:ThreadId

			$FragLink = $FragmentData.Link
			$FragLinkName = $FragmentData.Filename
			$FragmentID_Int = $FragmentData.Id
			$FragmentID_Str = "{0:d5}" -f $FragmentID_Int
			
			function l([Switch]$D, [Switch]$W,[Switch]$E, $Message) {
				if ($E) {
					throw "[$ThreadId]: $Message"
				} elseif ($W) {
					Write-Host "[$ThreadId]: $Message" -Foreground Yellow
				} elseif ($D) {
					Write-Host "[$ThreadId]: $Message" -Foreground DarkGray
				} else {
					Write-Host "[$ThreadId]: $Message"
				}
			}

			l -D "Downloading fragment $FragmentID_Str : $using:FragUrlBase$FragLink"
			iwr -WebSession $using:Session "$using:FragUrlBase$FragLink" -outfile "$using:VideoId--$using:Id/b-$FragmentID_Str.$using:Filetype"
			($using:existing).Add( $FragmentID_Int )
		}

		$existing -join "`n" | out-file -encoding utf8nobom -nonewline "$VideoId--$ThreadId.finished" -ea ignore

		l -D "playlist: sleeping $s"
		sleep $s
	}
	
	<# finished downloading!! post-process #>
	l "Merging fragments..."
	gci "$VideoId--$Id/*.$Filetype" | gc -AsByteStream -ReadCount 0 | set-content -AsByteStream "$VideoId--$Id/merged.bin"
	return @{Filename="$VideoId--$Id/merged.bin"; MediaType=( $ThreadId[0] )}
}

$VideoOffset = 0.0
$VideoFile = $null
$AudioOffset = 0.0
$AudioFile = $null
# fix desync
$BinFiles | % {
	$I = $_
	write-host ($I|out-default)

	if ($_.MediaType -eq 'v') {
		$VideoOffset = (ffprobe -v error -show_streams -show_format $I.Filename) | ? { $_ -like "start_time=*" } | Select-Object -first 1|  % replace start_time= ''
		$VideoFile = $_.Filename
	} else {
		$AudioOffset = (ffprobe -v error -show_streams -show_format $I.Filename) | ? { $_ -like "start_time=*" } | Select-Object -first 1|  % replace start_time= ''
		$AudioFile = $_.Filename
	}
}

Write-Host "voff=$VideoOffset aoff=$AudioOffset calculated=$(-1 * ($VideoOffset - $AudioOffset))"
ffmpeg -v error -y -itsoffset "$(-1 * ($VideoOffset - $AudioOffset))" -i $AudioFile -i $VideoFile -c copy "$VideoId.mp4"
ffmpeg -v error -y -itsoffset "$($VideoOffset - $AudioOffset)" -i $AudioFile -i $VideoFile -c copy "$VideoId-poffset.mp4"
gi "$VideoId.mp4","$VideoId-poffset.mp4"

Write-Host "$VideoID.mp4 should be correct, but there is a small chance the audio offset is backwards. If audio is desynced, check $VideoId-poffset.mp4"

exit