#!/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-api has been merged into main
    - feature-ui branch exists and has been merged
    - A merge commit exists (from three-way merge)
#>

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 checkout main" -ForegroundColor Yellow
    $allChecksPassed = $false
}

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

# Check if commits from feature-api are in main
$apiRoutesCommit = git log --all --grep="Add API routes" --oneline 2>$null
$healthCheckCommit = git log --all --grep="Add health check route" --oneline 2>$null

if ($apiRoutesCommit -and $healthCheckCommit) {
    # Check if these commits are in main's history
    $apiRoutesInMain = git log --grep="Add API routes" --oneline 2>$null
    $healthCheckInMain = git log --grep="Add health check route" --oneline 2>$null

    if ($apiRoutesInMain -and $healthCheckInMain) {
        Write-Host "[PASS] Commits from feature-api are merged into main" -ForegroundColor Green
    } else {
        Write-Host "[FAIL] Commits from feature-api not found in main" -ForegroundColor Red
        Write-Host "[HINT] Merge feature-api with: git merge feature-api" -ForegroundColor Yellow
        $allChecksPassed = $false
    }
} else {
    Write-Host "[FAIL] Expected commits from feature-api not found" -ForegroundColor Red
    Write-Host "[HINT] Did you run setup.ps1?" -ForegroundColor Yellow
    $allChecksPassed = $false
}

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

# Check if feature-ui branch exists
$featureUiBranch = git branch --list "feature-ui" 2>$null
if ($featureUiBranch) {
    Write-Host "[PASS] Branch 'feature-ui' exists" -ForegroundColor Green

    # Check if feature-ui has commits
    $uiCommitCount = git rev-list main..feature-ui --count 2>$null
    if ($uiCommitCount -gt 0) {
        Write-Host "[INFO] Branch 'feature-ui' has $uiCommitCount commit(s)" -ForegroundColor Cyan
    }
} else {
    Write-Host "[FAIL] Branch 'feature-ui' not found" -ForegroundColor Red
    Write-Host "[HINT] Create feature-ui with: git checkout -b feature-ui" -ForegroundColor Yellow
    $allChecksPassed = $false
}

# Check for merge commits (indicates three-way merge happened)
$mergeCommits = git log --merges --oneline 2>$null
if ($mergeCommits) {
    Write-Host "[PASS] Merge commit(s) found (three-way merge completed)" -ForegroundColor Green
} else {
    Write-Host "[FAIL] No merge commits found" -ForegroundColor Red
    Write-Host "[HINT] Create divergence: make commits on both main and feature-ui, then merge" -ForegroundColor Yellow
    $allChecksPassed = $false
}

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

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 learned about Git merging!" -ForegroundColor Cyan
    Write-Host "You now understand:" -ForegroundColor Cyan
    Write-Host "  - Fast-forward merges (when main hasn't changed)" -ForegroundColor White
    Write-Host "  - Three-way merges (when branches have diverged)" -ForegroundColor White
    Write-Host "  - How to use git merge to combine branches" -ForegroundColor White
    Write-Host "  - Merge commits and how to view them" -ForegroundColor White
    Write-Host "`nReady for the next module!" -ForegroundColor Green
    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
}