#requires -Version 5.1

$ErrorActionPreference = "Stop"

# Корень проекта определяется независимо от текущей папки PowerShell.
$ProjectRoot = Split-Path -Parent $PSScriptRoot
$ToolsDir = Join-Path $ProjectRoot "tools"
$OutputDir = Join-Path $ProjectRoot "output"

if (-not (Test-Path $OutputDir)) {
    New-Item -ItemType Directory -Path $OutputDir -Force | Out-Null
}

function Find-Tool {
    param(
        [Parameter(Mandatory = $true)]
        [string]$Name,

        [string[]]$LocalNames = @()
    )

    foreach ($localName in $LocalNames) {
        $localPath = Join-Path $ToolsDir $localName
        if (Test-Path $localPath -PathType Leaf) {
            return (Resolve-Path $localPath).Path
        }
    }

    $command = Get-Command $Name -ErrorAction SilentlyContinue
    if ($command) {
        return $command.Source
    }

    return $null
}

function Require-Tool {
    param(
        [Parameter(Mandatory = $true)]
        [string]$Name,

        [string[]]$LocalNames = @(),

        [string]$InstallHint = ""
    )

    $tool = Find-Tool -Name $Name -LocalNames $LocalNames

    if (-not $tool) {
        Write-Host ""
        Write-Host "ОШИБКА: не найдена зависимость '$Name'." -ForegroundColor Red
        Write-Host "Проверены:"
        Write-Host "  1. Папка: $ToolsDir"
        Write-Host "  2. Системная переменная PATH"

        if ($InstallHint) {
            Write-Host ""
            Write-Host $InstallHint
        }

        Write-Host ""
        Read-Host "Нажмите Enter для выхода"
        exit 1
    }

    return $tool
}

$YtDlp = Require-Tool `
    -Name "yt-dlp" `
    -LocalNames @("yt-dlp.exe", "yt-dlp.cmd", "yt-dlp.ps1") `
    -InstallHint "Скачать yt-dlp: https://github.com/yt-dlp/yt-dlp/releases/latest"

$Ffmpeg = Require-Tool `
    -Name "ffmpeg" `
    -LocalNames @("ffmpeg.exe") `
    -InstallHint "Скачать FFmpeg: https://www.gyan.dev/ffmpeg/builds/ffmpeg-release-full.7z"

$FfmpegDir = Split-Path -Parent $Ffmpeg

Write-Host ""
Write-Host "============================================================"
Write-Host "          СКАЧИВАНИЕ ВИДЕО С YOUTUBE"
Write-Host "============================================================"
Write-Host "Результат: $OutputDir"
Write-Host ""

$Url = Read-Host "Введите URL видео с YouTube"

if ([string]::IsNullOrWhiteSpace($Url)) {
    Write-Host ""
    Write-Host "ОШИБКА: ссылка не введена." -ForegroundColor Red
    Read-Host "Нажмите Enter для выхода"
    exit 1
}

$OutputTemplate = Join-Path $OutputDir "%(title)s.%(ext)s"

Write-Host ""
Write-Host "Скачивание видео в максимально доступном качестве..."
Write-Host ""

& $YtDlp `
    "-f" "bv*+ba/b" `
    "--ffmpeg-location" $FfmpegDir `
    "-o" $OutputTemplate `
    $Url

if ($LASTEXITCODE -ne 0) {
    Write-Host ""
    Write-Host "ОШИБКА: yt-dlp завершил работу с кодом $LASTEXITCODE." -ForegroundColor Red
    Read-Host "Нажмите Enter для выхода"
    exit $LASTEXITCODE
}

Write-Host ""
Write-Host "Готово." -ForegroundColor Green
Write-Host "Файл сохранён в: $OutputDir"
Write-Host ""
Read-Host "Нажмите Enter для выхода"