#!/usr/bin/env pwsh
# regenerate-solution.ps1 - Regenerate StellaOps.sln without duplicate projects
#
# This script:
# 1. Backs up the existing solution
# 2. Creates a new solution
# 3. Adds all .csproj files, skipping duplicates
# 4. Preserves solution folders where possible

param(
    [string]$SolutionPath = "src/StellaOps.sln",
    [switch]$DryRun
)

$ErrorActionPreference = "Stop"

# Canonical locations for test projects (in priority order)
# Later entries win when there are duplicates
$canonicalPatterns = @(
    # Module-local tests (highest priority)
    "src/*/__Tests/*/*.csproj",
    "src/*/__Libraries/__Tests/*/*.csproj",
    "src/__Libraries/__Tests/*/*.csproj",
    # Cross-module integration tests
    "src/__Tests/Integration/*/*.csproj",
    "src/__Tests/__Libraries/*/*.csproj",
    # Category-based cross-module tests
    "src/__Tests/chaos/*/*.csproj",
    "src/__Tests/security/*/*.csproj",
    "src/__Tests/interop/*/*.csproj",
    "src/__Tests/parity/*/*.csproj",
    "src/__Tests/reachability/*/*.csproj",
    # Single global tests
    "src/__Tests/*/*.csproj"
)

Write-Host "=== Solution Regeneration Script ===" -ForegroundColor Cyan
Write-Host "Solution: $SolutionPath"
Write-Host "Dry Run: $DryRun"
Write-Host ""

# Find all .csproj files
Write-Host "Finding all project files..." -ForegroundColor Yellow
$allProjects = Get-ChildItem -Path "src" -Filter "*.csproj" -Recurse |
    Where-Object { $_.FullName -notmatch "\\obj\\" -and $_.FullName -notmatch "\\bin\\" }

Write-Host "Found $($allProjects.Count) project files"

# Build a map of project name -> list of paths
$projectMap = @{}
foreach ($proj in $allProjects) {
    $name = $proj.BaseName
    if (-not $projectMap.ContainsKey($name)) {
        $projectMap[$name] = @()
    }
    $projectMap[$name] += $proj.FullName
}

# Find duplicates
$duplicates = $projectMap.GetEnumerator() | Where-Object { $_.Value.Count -gt 1 }
Write-Host ""
Write-Host "Found $($duplicates.Count) projects with duplicate names:" -ForegroundColor Yellow
foreach ($dup in $duplicates) {
    Write-Host "  $($dup.Key):" -ForegroundColor Red
    foreach ($path in $dup.Value) {
        Write-Host "    - $path"
    }
}

# Select canonical path for each project
function Get-CanonicalPath {
    param([string[]]$Paths)

    # Prefer module-local __Tests over global __Tests
    $moduleTests = $Paths | Where-Object { $_ -match "src\\[^_][^\\]+\\__Tests\\" }
    if ($moduleTests.Count -gt 0) { return $moduleTests[0] }

    # Prefer __Libraries/__Tests
    $libTests = $Paths | Where-Object { $_ -match "__Libraries\\__Tests\\" }
    if ($libTests.Count -gt 0) { return $libTests[0] }

    # Prefer __Tests over non-__Tests location in same parent
    $testsPath = $Paths | Where-Object { $_ -match "\\__Tests\\" }
    if ($testsPath.Count -gt 0) { return $testsPath[0] }

    # Otherwise, take first
    return $Paths[0]
}

# Build final project list
$finalProjects = @()
foreach ($entry in $projectMap.GetEnumerator()) {
    $canonical = Get-CanonicalPath -Paths $entry.Value
    $finalProjects += $canonical
}

Write-Host ""
Write-Host "Final project count: $($finalProjects.Count)" -ForegroundColor Green

if ($DryRun) {
    Write-Host ""
    Write-Host "=== DRY RUN - No changes made ===" -ForegroundColor Magenta
    Write-Host "Would add the following projects to solution:"
    $finalProjects | ForEach-Object { Write-Host "  $_" }
    exit 0
}

# Backup existing solution
$backupPath = "$SolutionPath.bak"
if (Test-Path $SolutionPath) {
    Copy-Item $SolutionPath $backupPath -Force
    Write-Host "Backed up existing solution to $backupPath" -ForegroundColor Gray
}

# Create new solution
Write-Host ""
Write-Host "Creating new solution..." -ForegroundColor Yellow
$slnDir = Split-Path $SolutionPath -Parent
$slnName = [System.IO.Path]::GetFileNameWithoutExtension($SolutionPath)

# Remove old solution
if (Test-Path $SolutionPath) {
    Remove-Item $SolutionPath -Force
}

# Create fresh solution
Push-Location $slnDir
dotnet new sln -n $slnName --force 2>$null
Pop-Location

# Add projects in batches (dotnet sln add can handle multiple)
Write-Host "Adding projects to solution..." -ForegroundColor Yellow
$added = 0
$failed = 0

foreach ($proj in $finalProjects) {
    try {
        $result = dotnet sln $SolutionPath add $proj 2>&1
        if ($LASTEXITCODE -eq 0) {
            $added++
            if ($added % 50 -eq 0) {
                Write-Host "  Added $added projects..." -ForegroundColor Gray
            }
        } else {
            Write-Host "  Failed to add: $proj" -ForegroundColor Red
            $failed++
        }
    } catch {
        Write-Host "  Error adding: $proj - $_" -ForegroundColor Red
        $failed++
    }
}

Write-Host ""
Write-Host "=== Summary ===" -ForegroundColor Cyan
Write-Host "Projects added: $added" -ForegroundColor Green
Write-Host "Projects failed: $failed" -ForegroundColor $(if ($failed -gt 0) { "Red" } else { "Green" })
Write-Host ""
Write-Host "Solution regenerated at: $SolutionPath"

# Verify
Write-Host ""
Write-Host "Verifying solution..." -ForegroundColor Yellow
$verifyResult = dotnet build $SolutionPath --no-restore -t:ValidateSolutionConfiguration 2>&1
if ($LASTEXITCODE -eq 0) {
    Write-Host "Solution validation passed!" -ForegroundColor Green
} else {
    Write-Host "Solution validation had issues - check manually" -ForegroundColor Yellow
}