// No code required for this foundational conceptual part.

<?php

// 1. Install PHPStan as a development dependency using Composer
// This command adds phpstan/phpstan to your project's composer.json
// and downloads the necessary packages.
// Navigate to your project root in the terminal and execute:
// composer require --dev phpstan/phpstan

// 2. Create a basic PHPStan configuration file (phpstan.neon)
// Place this file in the root of your project. It instructs PHPStan
// where to find your source code and what level of analysis to apply.
// For initial security analysis, start with a moderate level like 5 or 6
// to catch significant issues without being overwhelmed.

/*
// phpstan.neon content:

parameters:
    level: 6 # Or a higher level (up to 9) for stricter checks.
    paths:
        - src # Point PHPStan to your source code directory.
    autoload_files:
        # If you have global functions or non-Composer autoloader setup,
        # list files that need to be loaded before analysis.
        # - %rootDir%/../some_legacy_file.php

    # Security-focused ignored errors (example - adjust based on real findings)
    # We define specific patterns to ignore certain errors temporarily or permanently
    # if they are deemed false positives or acceptable risks for your project.
    ignoreErrors:
        # - '#Call to an undefined method App\\Service\\UserService::getUserName().#'
        # - '#Access to an undefined property App\\Entity\\User::$email.#'
        # - '#Method App\\Controller\\SecurityController::login() has no return type specified.#'
*/

// 3. Execute the first PHPStan analysis
// This command runs PHPStan on your 'src' directory (as configured in phpstan.neon)
// and outputs the findings to the console.
// In your terminal, from the project root, execute:
// vendor/bin/phpstan analyse

// If you did not create phpstan.neon, you can also run it directly like this:
// vendor/bin/phpstan analyse src --level 5

// Example PHP code with a potential security concern for PHPStan to detect:
// Imagine this in src/UserService.php
class UserService
{
    private $users = [
        1 => ['username' => 'admin', 'password' => 'hashed_password'],
        2 => ['username' => 'guest', 'password' => 'guest_password']
    ];

    public function findUserById(int $id)
    {
        // PHPStan might warn about returning potentially undefined array key if $id is not found
        // This could lead to a null/undefined access if not handled downstream, 
        // which could be a source of unexpected behavior or vulnerability.
        return $this->users[$id]; 
    }
    
    public function processInput(string $input)
    {
        // PHPStan can detect if $input is not strictly used as a string
        // or if sensitive operations are performed without type safety.
        if (is_numeric($input)) {
            // Potentially unsafe type juggling or comparison if $input is meant to be a string
            // PHPStan on higher levels can detect loose comparisons or type-unsafe operations.
            // For example, strict-rules would warn about '== true' instead of '=== true'
            return (int)$input > 100;
        }
        return false;
    }
}

<?php

// 1. Install security-focused PHPStan extensions
// Extensions expand PHPStan's capabilities by adding more specific rules.
// phpstan/phpstan-strict-rules is highly recommended for stricter type checking and error detection.
// phpstan/extension-installer auto-discovers extensions and registers them with PHPStan.

// In your terminal:
// composer require --dev phpstan/phpstan-strict-rules
// composer require --dev phpstan/extension-installer

// 2. Update your phpstan.neon to include extensions and higher levels
// Integrating extensions and raising the analysis level enhances the depth of security checks.
// Place this content in your phpstan.neon file.

/*
// phpstan.neon content (example):

parameters:
    level: 8 # Increase level for stricter checks. Levels 7-9 are very strict.
    paths:
        - src

    # Autoload files and extensions
    includes:
        # Include PHPStan's strict rules extension for more rigorous checks.
        - vendor/phpstan/phpstan-strict-rules/rules.neon

    # Example of a custom rule definition (conceptual):
    # Custom rules are powerful for enforcing project-specific security standards.
    # For instance, ensuring all user inputs are passed through a specific sanitizer function.
    rules:
        - App\PHPStan\Rules\NoDirectSuperglobalsRule # A custom rule class we'd create.

    # Baseline configuration (for existing codebases)
    # Generate a baseline to ignore existing errors and focus on new ones.
    # Run: vendor/bin/phpstan analyse --generate-baseline phpstan-baseline.neon
    # Then include it here:
    # - phpstan-baseline.neon
*/

// Example of a custom rule concept:
// Imagine you want to forbid direct use of $_GET, $_POST, $_REQUEST 
// to ensure all input goes through a validated wrapper.

// File: App/PHPStan/Rules/NoDirectSuperglobalsRule.php
// This is a simplified concept; actual custom rules require more boilerplate.
namespace App\PHPStan\Rules;

use PhpParser\Node;
use PhpParser\Node\Expr\ArrayDimFetch;
use PHPStan\Analyser\Scope;
use PHPStan\Rules\Rule;
use PHPStan\Rules\RuleErrorBuilder;

/**
 * @implements Rule<ArrayDimFetch>
 */
class NoDirectSuperglobalsRule implements Rule
{
    public function getNodeType(): string
    {
        return ArrayDimFetch::class;
    }

    public function processNode(Node $node, Scope $scope): array
    {
        if (!$node->var instanceof Node\Expr\Variable) {
            return [];
        }

        $variableName = $node->var->name;

        if (in_array($variableName, ['_GET', '_POST', '_REQUEST', '_SERVER'])) {
            return [
                RuleErrorBuilder::message(
                    sprintf('Direct access to superglobal $%s is forbidden. Use a validated input wrapper.', $variableName)
                )->build(),
            ];
        }

        return [];
    }
}

// To make PHPStan find your custom rule, you also need to configure it in phpstan.neon
// and ensure it's autoloaded. This often involves defining a `src` or `app` path in `paths:`
// and potentially `autoload_files:` or `scanFiles:` for legacy setups.

<?php

// 1. Example GitHub Actions Workflow for running PHPStan
// This YAML snippet demonstrates how to integrate PHPStan into a CI/CD pipeline.
// It ensures that every push or pull request triggers a static analysis scan.
// If PHPStan finds errors above a certain threshold (or any errors if strict), the build fails.

/*
// .github/workflows/phpstan.yml content:

name: PHPStan Analysis

on:
    push:
        branches:
            - main
            - develop
    pull_request:
        branches:
            - main
            - develop

jobs:
    phpstan:
        runs-on: ubuntu-latest

        steps:
        -   name: Checkout code
            uses: actions/checkout@v4

        -   name: Setup PHP
            uses: shivammathur/setup-php@v2
            with:
                php-version: '8.2' # Specify your PHP version
                extensions: intl, pdo_mysql # Add any required PHP extensions
                ini-values: post_max_size=256M, upload_max_filesize=256M
                tools: composer:v2 # Ensure Composer v2 is used

        -   name: Install Composer dependencies
            run: composer install --no-interaction --prefer-dist --optimize-autoloader

        -   name: Run PHPStan
            run: vendor/bin/phpstan analyse --configuration phpstan.neon --no-progress --error-format=github
            # --configuration phpstan.neon ensures your specific rules are used.
            # --no-progress is good for CI/CD logs.
            # --error-format=github formats errors for GitHub UI integration.
            # To ensure the build fails on errors, PHPStan will exit with a non-zero status code if issues are found.
            # You can also use a baseline here if you have one: --configuration phpstan.neon --no-progress --error-format=github --baseline phpstan-baseline.neon

        -   name: Generate PHPStan Baseline (optional, for new projects or updating baseline)
            # This step is typically run manually or on a dedicated branch/workflow,
            # not on every push/PR unless you specifically want to update the baseline constantly.
            # This example demonstrates how you *would* generate it.
            # run: vendor/bin/phpstan analyse --configuration phpstan.neon --generate-baseline phpstan-baseline.neon --memory-limit=2G
            # You would then commit the phpstan-baseline.neon file to your repository.

*/

// The core principle for CI/CD integration is to run the PHPStan command
// within your pipeline script. A non-zero exit code from PHPStan indicates
// that errors were found, which should then cause the CI build to fail.
// This enforces a "security gate" before merging or deploying code.

?>