#Requires -Version 5.1
<#
.SYNOPSIS
    Installs DupFinder on this workstation.
.DESCRIPTION
    - Verifies Docker Desktop is installed and running
    - Loads the pre-built Docker image (or builds from source as fallback)
    - Prompts for photos library path and data storage path
    - Writes a docker-compose.override.yml
    - Starts the container
    - Creates a desktop shortcut
.PARAMETER ForceReload
    Re-load the Docker image even if it's already present locally.
.EXAMPLE
    PowerShell -ExecutionPolicy Bypass -File install.ps1
#>
param(
    [switch]$ForceReload
)

Set-StrictMode -Version Latest
$ErrorActionPreference = "Stop"

$ScriptDir   = $PSScriptRoot
$AppDir      = "C:\ProgramData\DupFinder"
$ConfigFile  = "$AppDir\dupfinder.conf"
$OverrideYml = "$AppDir\docker-compose.override.yml"
$ComposeYml  = "$AppDir\docker-compose.yml"
$ImageName   = "dupfinder:latest"
$TarPath     = "$ScriptDir\image\dupfinder.tar"
$SourcePath  = "$ScriptDir\source"
$AppPort     = 8765

function Write-Step([string]$msg) { Write-Host "`n==> $msg" -ForegroundColor Cyan }
function Write-OK([string]$msg)   { Write-Host "    OK  $msg" -ForegroundColor Green }
function Write-Warn([string]$msg) { Write-Host "    !!  $msg" -ForegroundColor Yellow }
function Write-Fail([string]$msg) { Write-Host "`n[FAIL] $msg" -ForegroundColor Red }
function Pause-Continue {
    Write-Host "`nPress Enter to continue..." -NoNewline
    $null = Read-Host
}

# ── 1. Admin check ────────────────────────────────────────────────────────────
$principal = [Security.Principal.WindowsPrincipal][Security.Principal.WindowsIdentity]::GetCurrent()
if (-not $principal.IsInRole([Security.Principal.WindowsBuiltInRole]::Administrator)) {
    Write-Fail "This script must be run as Administrator."
    Write-Host "Right-click install.ps1 and choose 'Run as administrator', or use:"
    Write-Host "  PowerShell -ExecutionPolicy Bypass -File `"$PSCommandPath`""
    exit 1
}

Write-Host ""
Write-Host "  ====================================" -ForegroundColor Magenta
Write-Host "   DupFinder Installer" -ForegroundColor Magenta
Write-Host "  ====================================" -ForegroundColor Magenta
Write-Host ""

# ── 2. WSL2 check ─────────────────────────────────────────────────────────────
Write-Step "Checking WSL2..."
$wslOut = & wsl --status 2>&1
if ($LASTEXITCODE -ne 0) {
    Write-Warn "WSL2 is not installed or needs updating."
    Write-Host "    Installing WSL2 (requires internet + possible reboot)..."
    & wsl --install --no-distribution 2>&1 | Out-Null
    Write-Warn "A reboot may be required. After rebooting, re-run this installer."
    Pause-Continue
    exit 0
}
Write-OK "WSL2 is present"

# ── 3. Docker detection ───────────────────────────────────────────────────────
Write-Step "Checking Docker Desktop..."

$dockerExe = $null
$dockerCmd = Get-Command docker -ErrorAction SilentlyContinue
if ($dockerCmd) {
    $dockerExe = $dockerCmd.Source
} else {
    # Check known install locations
    $candidates = @(
        "$env:ProgramFiles\Docker\Docker\resources\bin\docker.exe",
        "$env:LOCALAPPDATA\Programs\Docker\Docker\resources\bin\docker.exe"
    )
    foreach ($c in $candidates) {
        if (Test-Path $c) { $dockerExe = $c; break }
    }
}

if (-not $dockerExe) {
    Write-Warn "Docker Desktop is not installed."

    $bundledInstaller = "$ScriptDir\assets\DockerDesktopInstaller.exe"
    if (Test-Path $bundledInstaller) {
        Write-Host "    Found bundled Docker Desktop installer. Installing..."
        Start-Process -Wait $bundledInstaller -ArgumentList "install --quiet --accept-license"
        Write-Warn "Docker Desktop was installed. A reboot may be required."
        Write-Host "    After rebooting, re-run this installer."
        Pause-Continue
        exit 0
    } else {
        Write-Host "    Opening Docker Desktop download page in your browser..."
        Start-Process "https://www.docker.com/products/docker-desktop/"
        Write-Host "    Install Docker Desktop, then re-run this script."
        Pause-Continue
        exit 0
    }
}
Write-OK "Docker executable found: $dockerExe"

# ── 4. Ensure Docker daemon is running ────────────────────────────────────────
Write-Step "Waiting for Docker daemon..."
$maxWait = 60
$waited  = 0
while ($waited -lt $maxWait) {
    $info = docker info 2>&1
    if ($LASTEXITCODE -eq 0) { break }
    if ($waited -eq 0) {
        # Try to start Docker Desktop
        $desktopExe = "$env:ProgramFiles\Docker\Docker\Docker Desktop.exe"
        if (Test-Path $desktopExe) {
            Write-Host "    Starting Docker Desktop..."
            Start-Process $desktopExe
        }
        Write-Host "    Waiting for Docker to become ready (up to ${maxWait}s)..."
        Write-Host "    If a Docker Desktop setup window appeared, please complete it."
    }
    Start-Sleep 3
    $waited += 3
    Write-Host "    ... ${waited}s" -NoNewline
}
Write-Host ""
docker info 2>&1 | Out-Null
if ($LASTEXITCODE -ne 0) {
    Write-Fail "Docker did not start within ${maxWait}s. Please start Docker Desktop manually and re-run."
    exit 1
}
Write-OK "Docker daemon is running"

# ── 5. docker compose V2 check ────────────────────────────────────────────────
docker compose version 2>&1 | Out-Null
if ($LASTEXITCODE -ne 0) {
    Write-Fail "docker compose (V2 plugin) not found. Please update Docker Desktop to 4.0+ and re-run."
    exit 1
}
Write-OK "docker compose V2 available"

# ── 6. Load / build image ─────────────────────────────────────────────────────
Write-Step "Preparing DupFinder Docker image..."
$existingImage = (docker images $ImageName --format "{{.ID}}" 2>$null)

if ($existingImage -and -not $ForceReload) {
    Write-OK "Image already loaded (use -ForceReload to replace it)"
} elseif (Test-Path $TarPath) {
    Write-Host "    Loading image from $TarPath ..."
    docker load -i $TarPath
    if ($LASTEXITCODE -ne 0) { Write-Fail "docker load failed."; exit 1 }
    Write-OK "Image loaded from tar"
} elseif (Test-Path "$SourcePath\Dockerfile") {
    Write-Warn "No pre-built image found. Building from source (requires internet)..."
    docker build -t $ImageName $SourcePath
    if ($LASTEXITCODE -ne 0) { Write-Fail "docker build failed."; exit 1 }
    Write-OK "Image built from source"
} else {
    Write-Fail "No image tar and no source Dockerfile found. Bundle may be incomplete."
    exit 1
}

# ── 7. Collect paths from user ────────────────────────────────────────────────
Write-Step "Configuration"
Write-Host ""

# Load existing config as defaults if re-running
$defaultPhotos = "C:\Photos"
$defaultData   = "C:\ProgramData\DupFinder\data"
if (Test-Path $ConfigFile) {
    Get-Content $ConfigFile | ForEach-Object {
        if ($_ -match '^PHOTOS_PATH=(.+)$') { $defaultPhotos = $Matches[1] }
        if ($_ -match '^DATA_PATH=(.+)$')   { $defaultData   = $Matches[1] }
    }
}

# Photos path
do {
    Write-Host "  Photos library path (read-only mount):"
    Write-Host "  Default: $defaultPhotos"
    $input = (Read-Host "  Path").Trim().Trim('"')
    if ([string]::IsNullOrWhiteSpace($input)) { $input = $defaultPhotos }
    $PhotosPath = $input
    if (-not (Test-Path $PhotosPath -PathType Container)) {
        Write-Warn "Path not found: $PhotosPath  (try again)"
    }
} while (-not (Test-Path $PhotosPath -PathType Container))
Write-OK "Photos: $PhotosPath"

# Data path
Write-Host ""
Write-Host "  Database / data storage path:"
Write-Host "  Default: $defaultData"
$input = (Read-Host "  Path").Trim().Trim('"')
if ([string]::IsNullOrWhiteSpace($input)) { $input = $defaultData }
$DataPath = $input
New-Item -ItemType Directory -Force -Path $DataPath | Out-Null
Write-OK "Data:   $DataPath"

# ── 8. Port conflict check ────────────────────────────────────────────────────
$portInUse = Test-NetConnection localhost -Port $AppPort `
             -InformationLevel Quiet -WarningAction SilentlyContinue 2>$null
if ($portInUse) {
    Write-Warn "Port $AppPort is already in use. DupFinder may already be running."
}

# ── 9. Write config and compose override ─────────────────────────────────────
Write-Step "Writing configuration..."
New-Item -ItemType Directory -Force -Path $AppDir | Out-Null

# Docker requires forward slashes
$PhotosDocker = $PhotosPath -replace '\\', '/' -replace '//', '/'
$DataDocker   = $DataPath   -replace '\\', '/' -replace '//', '/'

@"
PHOTOS_PATH=$PhotosPath
DATA_PATH=$DataPath
APP_PORT=$AppPort
COMPOSE_DIR=$AppDir
"@ | Set-Content $ConfigFile -Encoding UTF8

@"
services:
  dup-finder:
    ports:
      - "${AppPort}:8000"
    volumes:
      - "$PhotosDocker:/photos:ro"
      - "$DataDocker:/data"
"@ | Set-Content $OverrideYml -Encoding UTF8

# Copy base compose file
Copy-Item "$ScriptDir\docker-compose.yml" $ComposeYml -Force

# Copy start-stop helper
Copy-Item "$ScriptDir\dupfinder-start-stop.ps1" "$AppDir\dupfinder-start-stop.ps1" -Force

Write-OK "Config written to $AppDir"

# ── 10. Start container ───────────────────────────────────────────────────────
Write-Step "Starting DupFinder container..."
docker compose -f $ComposeYml -f $OverrideYml up -d --pull never
if ($LASTEXITCODE -ne 0) { Write-Fail "docker compose up failed."; exit 1 }
Write-OK "Container started"

# ── 11. Create desktop shortcut ───────────────────────────────────────────────
Write-Step "Creating desktop shortcut..."
$ShortcutPath = "$env:PUBLIC\Desktop\DupFinder.lnk"
$WshShell     = New-Object -ComObject WScript.Shell
$Shortcut     = $WshShell.CreateShortcut($ShortcutPath)
$Shortcut.TargetPath   = "powershell.exe"
$Shortcut.Arguments    = "-ExecutionPolicy Bypass -WindowStyle Hidden -File `"$AppDir\dupfinder-start-stop.ps1`" -Action open"
$Shortcut.Description  = "Open DupFinder Duplicate Photo Scanner"
$Shortcut.WindowStyle  = 7  # Minimized — hides the PS window
$Shortcut.Save()
Write-OK "Shortcut created: $ShortcutPath"

# ── 12. Done ──────────────────────────────────────────────────────────────────
Write-Host ""
Write-Host "  ============================================" -ForegroundColor Green
Write-Host "   DupFinder installed successfully!" -ForegroundColor Green
Write-Host "   Open: http://localhost:$AppPort" -ForegroundColor Green
Write-Host "   Or double-click DupFinder on your desktop." -ForegroundColor Green
Write-Host "  ============================================" -ForegroundColor Green
Write-Host ""

# Open browser
$open = Read-Host "Open DupFinder in browser now? (Y/n)"
if ($open -ne 'n' -and $open -ne 'N') {
    Start-Process "http://localhost:$AppPort"
}