const fs = require('fs');
const path = require('path');
require('dotenv').config({ path: path.resolve(__dirname, '../../src/.env') });

/**
 * @fileoverview Automatisierungsskript für den Multi-Repository SAP-Deprecation Scan.
 * Durchsucht lokale Unterordner (Repositories) rekursiv nach SAP- und REST-Endpunkten,
 * gleicht diese über die FastAPI ab und generiert einen zusammenfassenden Report.
 * @author MBT
 * @version 1.3 (Zeigt in Details nur veränderte/abgekündigte Endpunkte)
 */


// --- KONFIGURATION ---

const BASE_PATH = './'; 
const FASTAPI_URL = 'http://127.0.0.1:8000/informations/bulk';
const OUTPUT_FILE = './sap_api_scan_report.txt';
const IGNORED_DIRS = ['node_modules', '.git', '__pycache__', 'venv', 'dist', 'build', '.idea', '.vscode'];

const headers = {
    "X-API-Key": process.env.READONLY_APIKEY
};

// Optimierte Regex (Case-Insensitive)
const ENDPOINT_REGEX = /\b(?:\/?)(?:v\d+|sap)\/[a-zA-Z0-9_\-\/{}]*(?:\/[a-zA-Z0-9_\-\/{}]+)*/i;


// --- FUNKTIONEN ---

function getRepositories(baseDir) {
    return fs.readdirSync(baseDir).filter(file => {
        const fullPath = path.join(baseDir, file);
        return fs.statSync(fullPath).isDirectory() && !IGNORED_DIRS.includes(file);
    });
}

function walkSync(dir, filelist = []) {
    const files = fs.readdirSync(dir);
    files.forEach(file => {
        const filepath = path.join(dir, file);
        const stat = fs.statSync(filepath);
        
        if (stat.isDirectory()) {
            if (!IGNORED_DIRS.includes(file)) {
                walkSync(filepath, filelist);
            }
        } else {
            filelist.push(filepath);
        }
    });
    return filelist;
}

function scanRepositoryForEndpoints(repoPath, repoName) {
    console.log(`\n🔍 [${repoName}] Starte rekursiven Scan im Ordner: ${path.resolve(repoPath)}...`);
    const files = walkSync(repoPath);
    const endpointLocations = {}; 
    let checkedFilesCount = 0;

    files.forEach(file => {
        if (
            file.endsWith('scan_repo.js') || 
            file.endsWith('scan_all_repos.js') || 
            file.endsWith('.txt') || 
            file.endsWith('.json') || 
            file.endsWith('.md') ||
            file.includes(path.basename(OUTPUT_FILE))
        ) {
            return;
        }

        checkedFilesCount++;

        try {
            const content = fs.readFileSync(file, 'utf8');
            
            if (!/sap|v\d+/i.test(content)) {
                return;
            }

            const lines = content.split(/\r?\n/);

            lines.forEach((lineText, index) => {
                const lineNumber = index + 1;
                const match = lineText.match(ENDPOINT_REGEX);

                if (match) {
                    const endpoint = match[0].trim();
                    if (endpoint.length >= 4) { 
                        if (!endpointLocations[endpoint]) {
                            endpointLocations[endpoint] = [];
                        }
                        
                        const relativePath = path.relative(BASE_PATH, file);
                        endpointLocations[endpoint].push({
                            file: relativePath,
                            line: lineNumber
                        });

                        console.log(`   ✨ Treffer in [${repoName}]: "${endpoint}" gefunden in ${relativePath}:${lineNumber}`);
                    }
                }
            });
        } catch (err) {
            if (err.code !== 'EISDIR' && !file.match(/\.(png|jpg|jpeg|gif|ico|zip|tar|gz|pdf|exe|dll)$/i)) {
                console.warn(`⚠️ Konnte Datei nicht lesen: ${file} (${err.message})`);
            }
        }
    });

    console.log(`🏁 [${repoName}] Scan beendet. ${checkedFilesCount} Dateien durchsucht. ${Object.keys(endpointLocations).length} eindeutige Endpunkte gefunden.`);
    return endpointLocations;
}

async function checkEndpoints(endpoints, batchSize = 25) {
    const consolidatedResult = {
        total_checked: 0,
        results: []
    };

    for (let i = 0; i < endpoints.length; i += batchSize) {
        const batch = endpoints.slice(i, i + batchSize);
        console.log(`   ⏳ Sende Batch ${Math.floor(i / batchSize) + 1} (${batch.length} Endpunkte)...`);

        const params = new URLSearchParams();
        batch.forEach(ep => params.append("endpoints", ep));

        try {
            const response = await fetch(`${FASTAPI_URL}?${params.toString()}`, { method: "GET", headers: headers });
            if (!response.ok) {
                throw new Error(`Server meldete Status ${response.status}`);
            }
            
            const batchJson = await response.json();
            
            consolidatedResult.total_checked += batchJson.total_checked || batch.length;
            if (batchJson.results && Array.isArray(batchJson.results)) {
                consolidatedResult.results.push(...batchJson.results);
            }
        } catch (error) {
            throw new Error(`Fehler in Batch ab Index ${i}: ${error.message}`);
        }
    }

    return consolidatedResult;
}

/**
 * Steuert den Scan-Workflow und baut die aggregierte Zusammenfassung sowie den gefilterten Detailbericht.
 */
async function runMultiRepoScan() {
    const repos = getRepositories(BASE_PATH);
    
    if (repos.length === 0) {
        console.log("⚠️ Keine Scan-fähigen Unterordner (Repositories) gefunden!");
        return;
    }

    console.log(`📂 ${repos.length} Repositories für den Scan gefunden.`);

    // Statistik-Zähler für die Zusammenfassung
    const stats = {
        totalRepos: repos.length,
        reposWithEndpoints: 0,
        totalEndpointsFound: 0,
        statusActive: 0,
        statusDeprecated: 0,
        statusChanged: 0,
        statusUnknown: 0
    };

    let detailedReportBody = '';

    // Schleife über alle gefundenen Repository-Ordner
    for (const repoName of repos) {
        const repoPath = path.join(BASE_PATH, repoName);
        console.log(`\n--------------------------------------------------`);
        console.log(`📦 Verarbeite Repository: ${repoName.toUpperCase()}`);
        console.log(`--------------------------------------------------`);

        const endpointLocations = scanRepositoryForEndpoints(repoPath, repoName);
        const uniqueEndpoints = Object.keys(endpointLocations);

        if (uniqueEndpoints.length === 0) {
            console.log(`ℹ️ Keine SAP-Endpunkte in [${repoName}] gefunden.`);
            continue;
        }

        stats.reposWithEndpoints++;
        stats.totalEndpointsFound += uniqueEndpoints.length;

        console.log(`🚀 ${uniqueEndpoints.length} Endpunkte in [${repoName}] gefunden. Sende Abfrage an FastAPI...`);

        try {
            const apiResult = await checkEndpoints(uniqueEndpoints);
            let repoIssuesContent = ''; // Puffer für problematische Endpunkte in diesem spezifischen Repo

            apiResult.results.forEach(item => {
                const messageLower = item.message.toLowerCase();
                const statusLower = (item.status || '').toLowerCase();

                // Status für die Statistik auswerten
                const isNoHit = messageLower.includes("keine sap-änderungen oder deprecations gefunden");
                let isIssue = false;
                
                if (isNoHit || statusLower === 'active' || statusLower === 'ok') {
                    stats.statusActive++;
                } else if (statusLower.includes('deprecat')) {
                    stats.statusDeprecated++;
                    isIssue = true;
                } else if (statusLower.includes('chang') || statusLower.includes('modif')) {
                    stats.statusChanged++;
                    isIssue = true;
                } else {
                    stats.statusUnknown++;
                    isIssue = true; // Unbekannte Stati sicherheitshalber auch auflisten
                }

                // Nur wenn ein Problem/eine Änderung vorliegt, wird der Endpunkt im Detailbericht aufgelistet
                if (isIssue) {
                    const locations = endpointLocations[item.endpoint] || [];
                    const locationString = locations
                        .map(loc => `${loc.file}:${loc.line}`)
                        .join(', ');

                    let logLine = `[❗Warning] Endpoint: ${item.endpoint}\n`;
                    logLine += `   Files: ${locationString}\n`;
                    logLine += `   Status:   ${item.status}\n`;
                    logLine += `   Details:  ${item.message}\n`;
                    logLine += `   Deprecated in Quality:  ${item.deprecated[0]}\n`;
                    logLine += `   Deprecated in Production:  ${item.deprecated[1]}\n`;
                    logLine += `   Decommissioned in Quality:  ${item.decommissioned[0]}\n`;
                    logLine += `   Decommissioned in Production:  ${item.decommissioned[1]}\n`;
                    
                    console.log(logLine);
                    repoIssuesContent += logLine + "\n";
                }
            });

            // Falls dieses Repo veränderte/abgekündigte Endpunkte hatte, hänge sie an den Report an
            if (repoIssuesContent.length > 0) {
                detailedReportBody += `📦 REPOSITORY: ${repoName}\n`;
                detailedReportBody += `--------------------------------------------------\n`;
                detailedReportBody += repoIssuesContent;
                detailedReportBody += `\n`;
            }

        } catch (error) {
            console.error(`❌ Fehler bei API-Abfrage für [${repoName}]:`, error.message);
            detailedReportBody += `📦 REPOSITORY: ${repoName}\n -> API-Fehler bei der Abfrage: ${error.message}\n\n`;
        }
    }

    // Zusammenbau des finalen Berichts (Zusammenfassung ganz oben!)
    let finalReportContent = `======================================================================\n`;
    finalReportContent += ` GLOBAL SAP DEPRECATION SCAN REPORT - ${new Date().toLocaleString()}\n`;
    finalReportContent += `======================================================================\n\n`;
    
    finalReportContent += `📊 SUMMARY:\n`;
    finalReportContent += `----------------------------------------------------------------------\n`;
    finalReportContent += ` Total Repositories Scanned:   ${stats.totalRepos}\n`;
    finalReportContent += ` Repositories with Findings:   ${stats.reposWithEndpoints}\n`;
    finalReportContent += ` Total Endpoints Detected:     ${stats.totalEndpointsFound}\n\n`;
    finalReportContent += ` ENDPOINT STATUS OVERVIEW:\n`;
    finalReportContent += `  🟢 Active / Unchanged Endpoints:      ${stats.statusActive}\n`;
    finalReportContent += `  🟡 Modified Endpoints (Changed):      ${stats.statusChanged}\n`;
    finalReportContent += `  🔴 Obsolete Endpoints (Deprecated):   ${stats.statusDeprecated}\n`;
    if (stats.statusUnknown > 0) {
        finalReportContent += `  ⚪ Unknown / Unclear Status:          ${stats.statusUnknown}\n`;
    }
    finalReportContent += `======================================================================\n\n\n`;
    
    // Details (filtered issues only!) appended below
    finalReportContent += `📝 ACTIONABLE DETAILS & DETECTED ISSUES (Filtered):\n`;
    finalReportContent += ` (Only modified or deprecated endpoints are listed below)\n`;
    finalReportContent += `======================================================================\n\n`;
    
    if (detailedReportBody.length === 0) {
        finalReportContent += `🎉 Excellent! No modified or deprecated endpoints were found in any of the repositories.\n`;
    } else {
        finalReportContent += detailedReportBody;
    }

    // Gesamtergebnis in Datei schreiben
    try {
        fs.writeFileSync(OUTPUT_FILE, finalReportContent, 'utf8');
        console.log(`\n💾 Der globale Bericht wurde erfolgreich gespeichert: ${path.resolve(OUTPUT_FILE)}`);
    } catch (err) {
        console.error("❌ Bericht konnte nicht geschrieben werden:", err.message);
    }
}

// --- START ---
runMultiRepoScan();