# Friendly Configuration
$TMP_DIR = "$env:TEMP\jpeg_optimizer"
$QUALITY = 100                 # Maximum quality setting
$PRESERVE_METADATA = $true     # Keep EXIF/GPS data by default
$KEEP_ORIGINAL = $true         # Safety default for new users

# Visual Feedback
$SUCCESS = "✅"
$INFO = "ℹ️"
$WARNING = "⚠️"
$ERROR = "❌"

# Setup environment
if (Test-Path $TMP_DIR) {
    Remove-Item -Recurse -Force $TMP_DIR
}
New-Item -ItemType Directory -Force -Path $TMP_DIR

# Check for mozjpeg
if (-not (Get-Command mozjpeg -ErrorAction SilentlyContinue)) {
    Write-Host "$WARNING 'mozjpeg' not found. Install it first."
    exit 1
}

# Function to test compression with different parameters
function Test-Compression {
    param (
        [string]$input
    )

    # Temp file to store results
    $R0 = [System.IO.Path]::GetTempFileName()
    $R1 = [System.IO.Path]::GetTempFileName()

    $best_size = [Int64]::MaxValue
    $best_params = ""

    # List of parameter sets to test
    $param_sets = @(
        "-dct float -quant-table 1 -nojfif -dc-scan-opt 2",
        "-dct float -quant-table 2 -nojfif -dc-scan-opt 2",
        "-dct float -quant-table 3 -nojfif -dc-scan-opt 2",
        "-dct float -tune-ms-ssim -nojfif -dc-scan-opt 2",
        "-dct float -tune-ms-ssim -quant-table 3 -nojfif -dc-scan-opt 2",
        "-dct float -tune-ssim -nojfif -dc-scan-opt 2",
        "-dct float -tune-ssim -quant-table 3 -nojfif -dc-scan-opt 2"
    )

    # Test each parameter set
    foreach ($param in $param_sets) {
        $cmd = "mozjpeg -memdst $param `"$input`" > $R0 2>&1"
        Invoke-Expression $cmd

        $compressed_size = (Get-Item $R0).Length

        if ($compressed_size -lt $best_size) {
            $best_size = $compressed_size
            $best_params = $param
        }
    }

    # Clean up temp files
    Remove-Item $R0

    return $best_params
}

# Function to optimize a single image
function Optimize-Image {
    param (
        [string]$input
    )

    Write-Host "$INFO Processing: $(Split-Path -Leaf $input)"

    # Get best compression parameters
    $best_params = Test-Compression -input $input

    # Run compression with best parameters
    $output = "$input.opti.jpg"
    $cmd = "mozjpeg -memdst $best_params `"$input`" > `"$output`""
    Invoke-Expression $cmd

    # Compare sizes
    $original_size = (Get-Item $input).length
    $new_size = (Get-Item $output).length

    if ($new_size -lt $original_size) {
        Write-Host "$SUCCESS Size reduced: $([math]::Round($original_size / 1KB))KB → $([math]::Round($new_size / 1KB))KB"

        # Create safe backup with original extension if required
        if ($KEEP_ORIGINAL) {
            $optimized_file = "$($input.Substring(0, $input.LastIndexOf('.')))_optimized$($input.Substring($input.LastIndexOf('.')))"
            Move-Item $output $optimized_file
        } else {
            Move-Item $output $input
        }
    } else {
        Write-Host "$WARNING No optimization needed - file already optimal"
        Remove-Item $output
    }
}

# Argument parsing (simplified for PowerShell)
$FILES = @()
foreach ($arg in $args) {
    if (Test-Path $arg) {
        $FILES += $arg
    }
}

# Main processing
if ($FILES.Count -eq 0) {
    Write-Host "$WARNING No valid files/folders provided"
    exit 1
}

Write-Host "$INFO Found $($FILES.Count) files to process"
foreach ($file in $FILES) {
    Optimize-Image -input $file
}

Write-Host "$SUCCESS Optimization complete!"

# Ask user if they want to replace original files
$response = Read-Host "Replace original jpg or png files with compressed .opti.jpg backups? Press Y for YES or N for NO"
if ($response -match '^[yY]$') {
    Get-ChildItem -Recurse -Filter '*.opti.jpg' | ForEach-Object {
        $original = $_.FullName.Substring(0, $_.FullName.LastIndexOf('.'))
        Move-Item $_.FullName -Destination $original -Force
        Write-Host "$SUCCESS Replaced: $original"
    }
    Write-Host "Original files replaced."
} else {
    Write-Host "Original and compressed files were preserved. Compressed files have .opti.jpg suffix."
}