#!/usr/bin/env tsx

/**
 * SQLite Fallback System Demonstration
 *
 * Shows how the fallback system automatically selects the best available
 * SQLite implementation and gracefully degrades if libraries are missing
 */

import { SQLiteMemoryManager } from "./sqlite-manager.js";
import {
  detectSQLiteImplementations,
  SQLiteImplementation,
} from "./sqlite-adapter.js";
import { Logger } from "../utils/logger.js";

const logger = new Logger("SQLiteFallbackDemo");

async function demonstrateFallbackSystem() {
  logger.info("🚀 SQLite Fallback System Demonstration");
  logger.info("=====================================");

  // Show detection results
  logger.info("1. Detecting available SQLite implementations...");
  const detection = await detectSQLiteImplementations();

  logger.info("Available implementations:", detection.available);
  logger.info("Recommended implementation:", detection.recommended);

  if (Object.keys(detection.errors).length > 0) {
    logger.warn("Failed implementations:", Object.keys(detection.errors));
  }

  // Demonstrate each available implementation
  for (const impl of detection.available) {
    await demonstrateImplementation(impl);
  }

  // Show fallback behavior by testing with preferred implementation
  await demonstrateFallbackBehavior();

  logger.info("🎉 SQLite Fallback System Demonstration Complete!");
}

async function demonstrateImplementation(implementation: SQLiteImplementation) {
  logger.info(`\\n2. Testing ${implementation} implementation...`);

  const manager = await SQLiteMemoryManager.create(
    `.swarm/demo-${implementation}.db`,
    implementation,
  );

  // Store some demo data with hierarchical namespaces
  await manager.store({
    key: `demo-${implementation}`,
    value: {
      message: `Hello from ${implementation}!`,
      timestamp: Date.now(),
      features: ["fallback", "cross-platform", "performance"],
    },
    namespace: `demo/implementations/${implementation}`,
  });

  // Store additional data in different namespace levels
  await manager.store({
    key: "config",
    value: {
      version: "1.0",
      settings: { performance: "high", compatibility: "universal" },
    },
    namespace: `demo/config`,
  });

  // Retrieve and display
  const data = await manager.retrieve(
    `demo-${implementation}`,
    `demo/implementations/${implementation}`,
  );
  logger.info(`Retrieved data:`, data.value);

  // Test namespace search with wildcards
  const allDemoData = await manager.search("*", "demo/*");
  logger.info(
    `Found ${allDemoData.length} entries in demo namespace hierarchy`,
  );

  // Store metrics
  await manager.recordMetric(
    `${implementation}_performance`,
    Math.random() * 100,
    "ms",
  );

  // Get metrics summary
  const metrics = await manager.getMetricsSummary(
    `${implementation}_performance`,
  );
  logger.info(`Metrics for ${implementation}:`, metrics);

  // Test connection
  const connectionOk = await manager.testConnection();
  logger.info(`Connection test: ${connectionOk ? "✅ PASS" : "❌ FAIL"}`);

  // Show implementation info
  const info = await manager.getImplementationInfo();
  logger.info(`Using: ${info.name}, Available: [${info.available.join(", ")}]`);

  manager.close();
  logger.info(`✅ ${implementation} test complete`);
}

async function demonstrateFallbackBehavior() {
  logger.info("\\n3. Demonstrating fallback behavior...");

  // Try to create with non-existent implementation
  try {
    logger.info("Creating manager with automatic fallback...");
    const manager = await SQLiteMemoryManager.create(".swarm/demo-fallback.db");

    const info = await manager.getImplementationInfo();
    logger.info(`Fallback selected: ${info.name}`);
    logger.info(`Priority order was: better-sqlite3 > sqlite3 > sql.js`);

    // Test cross-implementation compatibility with hierarchical namespaces
    await manager.store({
      key: "cross-platform-test",
      value: {
        message: "This data works across all SQLite implementations!",
        compatibility: ["better-sqlite3", "sqlite3", "sql.js"],
        features: {
          ttl: "Time-to-live support",
          namespaces: "Hierarchical multi-tenant isolation",
          search: "Pattern-based search with wildcards",
          metrics: "Performance tracking by namespace",
          tables: "12 specialized tables",
        },
      },
      namespace: "compatibility/cross-platform",
    });

    // Store additional namespace data
    await manager.store({
      key: "performance-data",
      value: { benchmarks: { read: "1000 ops/sec", write: "800 ops/sec" } },
      namespace: "compatibility/performance",
    });

    await manager.store({
      key: "feature-flags",
      value: { hierarchicalNamespaces: true, wildcardSearch: true },
      namespace: "compatibility/features",
    });

    const result = await manager.retrieve(
      "cross-platform-test",
      "compatibility/cross-platform",
    );
    logger.info("Cross-platform data test:", result.value.message);

    // Test namespace operations
    const namespaceInfo = await manager.getNamespaceInfo("compatibility/*");
    logger.info("Namespace info:", namespaceInfo);

    // Test listing all entries in compatibility namespace
    const compatibilityEntries = await manager.list("compatibility/*");
    logger.info(
      `Found ${compatibilityEntries.length} entries in compatibility namespace hierarchy`,
    );

    // Test namespace metrics
    const metrics = await manager.getNamespaceMetrics("compatibility/*");
    logger.info("Namespace metrics:", metrics);

    manager.close();
    logger.info("✅ Fallback behavior test complete");
  } catch (error) {
    logger.error("Fallback test failed:", error);
  }
}

async function showSystemCapabilities() {
  logger.info("\\n4. System Capabilities Summary");
  logger.info("===============================");

  const capabilities = {
    "Cross-Platform": "✅ Works on any Node.js environment",
    "Fallback Hierarchy": "✅ better-sqlite3 → sqlite3 → sql.js",
    "Performance Optimized": "✅ Uses fastest available implementation",
    "WASM Compatibility": "✅ sql.js provides universal fallback",
    "12 Specialized Tables": "✅ All work across implementations",
    "Hierarchical Namespaces":
      "✅ Multi-level organization (e.g., app/module/feature)",
    "Namespace Wildcards": "✅ Pattern matching with * and ** support",
    "Memory Management": "✅ TTL, cleanup, validation",
    "Namespace Operations": "✅ List, delete, info, metrics by namespace",
    "Advanced Search": "✅ Key/value patterns, sorting, filtering",
    "Metrics & Analytics": "✅ Performance tracking per namespace",
    "Error Handling": "✅ Graceful degradation with validation",
    "Async Operations": "✅ Promise-based API",
    "ES Module Support": "✅ Modern JavaScript imports",
  };

  for (const [feature, status] of Object.entries(capabilities)) {
    logger.info(`${feature}: ${status}`);
  }
}

// Main execution
if (import.meta.url === `file://${process.argv[1]}`) {
  demonstrateFallbackSystem()
    .then(() => showSystemCapabilities())
    .catch((error) => {
      logger.error("Demo failed:", error);
      process.exit(1);
    });
}

export { demonstrateFallbackSystem, demonstrateImplementation };