#!/usr/bin/env pwsh
<#
.SYNOPSIS
    Verifies the Module 04 challenge solution.

.DESCRIPTION
    This script checks that:
    - The challenge directory exists
    - A Git repository exists
    - Currently on main branch
    - feature-login has been merged into main
    - A merge commit exists (three-way merge)
    - Login functionality is present on main
#>

Write-Host "`n=== Verifying Module 04 Solution ===" -ForegroundColor Cyan

$allChecksPassed = $true

# Check if challenge directory exists
if (-not (Test-Path "challenge")) {
    Write-Host "[FAIL] Challenge directory not found. Did you run setup.ps1?" -ForegroundColor Red
    exit 1
}

Set-Location "challenge"

# Check if git repository exists
if (-not (Test-Path ".git")) {
    Write-Host "[FAIL] Not a git repository. Did you run setup.ps1?" -ForegroundColor Red
    Set-Location ..
    exit 1
}

# Check current branch is main
$currentBranch = git branch --show-current 2>$null
if ($currentBranch -eq "main") {
    Write-Host "[PASS] Currently on main branch" -ForegroundColor Green
} else {
    Write-Host "[FAIL] Not on main branch (currently on: $currentBranch)" -ForegroundColor Red
    Write-Host "[HINT] Switch to main with: git switch main" -ForegroundColor Yellow
    $allChecksPassed = $false
}

# Check if feature-login branch exists
$featureLoginBranch = git branch --list "feature-login" 2>$null
if ($featureLoginBranch) {
    Write-Host "[PASS] Branch 'feature-login' exists" -ForegroundColor Green
} else {
    Write-Host "[INFO] Branch 'feature-login' not found (may have been deleted after merge)" -ForegroundColor Cyan
}

# Check if login.py exists (should be on main after merge)
if (Test-Path "login.py") {
    Write-Host "[PASS] File 'login.py' exists on main (from feature-login merge)" -ForegroundColor Green
} else {
    Write-Host "[FAIL] File 'login.py' not found on main" -ForegroundColor Red
    Write-Host "[HINT] This file should appear after merging feature-login into main" -ForegroundColor Yellow
    $allChecksPassed = $false
}

# Check if app.py contains login integration
if (Test-Path "app.py") {
    $appContent = Get-Content "app.py" -Raw
    if ($appContent -match "login") {
        Write-Host "[PASS] app.py contains login integration" -ForegroundColor Green
    } else {
        Write-Host "[FAIL] app.py doesn't contain login integration" -ForegroundColor Red
        Write-Host "[HINT] After merging, app.py should import and use the login module" -ForegroundColor Yellow
        $allChecksPassed = $false
    }
} else {
    Write-Host "[FAIL] app.py not found" -ForegroundColor Red
    $allChecksPassed = $false
}

# Check for merge commit (indicates three-way merge happened)
$mergeCommits = git log --merges --oneline 2>$null
if ($mergeCommits) {
    Write-Host "[PASS] Merge commit found (three-way merge completed)" -ForegroundColor Green

    # Get the merge commit message
    $mergeMessage = git log --merges --format=%s -1 2>$null
    Write-Host "[INFO] Merge commit message: '$mergeMessage'" -ForegroundColor Cyan
} else {
    Write-Host "[FAIL] No merge commit found" -ForegroundColor Red
    Write-Host "[HINT] Merge feature-login into main with: git merge feature-login" -ForegroundColor Yellow
    $allChecksPassed = $false
}

# Check if both branches contributed commits (true three-way merge)
$totalCommits = git rev-list --count HEAD 2>$null
if ($totalCommits -ge 4) {
    Write-Host "[PASS] Repository has $totalCommits commits (branches diverged properly)" -ForegroundColor Green
} else {
    Write-Host "[WARN] Repository has only $totalCommits commits (expected at least 4)" -ForegroundColor Yellow
    Write-Host "[INFO] This might still be correct if you deleted commits" -ForegroundColor Cyan
}

Set-Location ..

# Final summary
if ($allChecksPassed) {
    Write-Host "`n" -NoNewline
    Write-Host "=====================================" -ForegroundColor Green
    Write-Host "   CONGRATULATIONS! CHALLENGE PASSED!" -ForegroundColor Green
    Write-Host "=====================================" -ForegroundColor Green
    Write-Host "`nYou've successfully completed your first branch merge!" -ForegroundColor Cyan
    Write-Host "You now understand:" -ForegroundColor Cyan
    Write-Host "  - How to merge branches with git merge" -ForegroundColor White
    Write-Host "  - What a merge commit is and why it's created" -ForegroundColor White
    Write-Host "  - How divergent branches are combined" -ForegroundColor White
    Write-Host "  - How to visualize merges with git log --graph" -ForegroundColor White
    Write-Host "`nNext up: Module 05 - Merge Conflicts!" -ForegroundColor Yellow
    Write-Host "You'll learn what happens when Git can't automatically merge." -ForegroundColor Cyan
    Write-Host ""
} else {
    Write-Host "`n[SUMMARY] Some checks failed. Review the hints above and try again." -ForegroundColor Red
    Write-Host "[INFO] You can run this verification script as many times as needed." -ForegroundColor Yellow
    Write-Host ""
    exit 1
}