$ErrorActionPreference = "Stop"
$ProgressPreference = "SilentlyContinue"

$url = "https://archive.org/details/CNBC_20191029_170000_The_Exchange"
$savePath = "C:\Temp"

$showName = Split-Path -Path $url -Leaf
$showSavePath = [IO.Path]::Combine($savePath, $showName)
if (!(Test-Path -Path $showSavePath)) { $null = mkdir $showSavePath }

$page = Invoke-WebRequest -Uri $url -UseBasicParsing
if (!($page.Content -match "js-tv3-init.+?value='(.+?)'")) { throw "Failed to extract video segments from web page" }

$videoUrls = ($Matches[1] | ConvertFrom-Json).'TV3.clipstream_clips'
$segmentCount = 1
$ffmpegFileList = [IO.Path]::Combine($showSavePath, "ffmpegJoin.txt")
foreach ($videoUrl in $videoUrls)
{
  $segmentFileName = [IO.Path]::Combine($showSavePath, "$($showName)_$($segmentCount.ToString('0000')).mp4")

  Write-Output "Downloading '$($videoUrl)' to '$($segmentFileName)'"
  Invoke-WebRequest -Uri $videoUrl -UseBasicParsing -OutFile $segmentFileName

  "file '$($segmentFileName -replace "\\", "/")'" | Out-File -FilePath $ffmpegFileList -Encoding ascii -Append

  $segmentCount++

  #Start-Sleep -Milliseconds (Get-Random -Minimum 250 -Maximum 1500)
}

$joinedVideoFileName = $segmentFileName = [IO.Path]::Combine($showSavePath, "$($showName).mp4")
$ffArgs = @("-f concat", "-safe 0", "-i", "`"$ffmpegFileList`"", "-c copy", "`"$joinedVideoFileName`"")

Start-Process -FilePath ffmpeg -ArgumentList $ffArgs -Wait -NoNewWindow