import { App, Context, staticFiles } from "fresh";
import { type State } from "./utils.ts";
import { loadSync } from "$std/dotenv/mod.ts";
import { sql } from "drizzle-orm";

// Allow empty values for optional Stripe variables
loadSync({ allowEmptyValues: true, export: true });
import { checkDatabaseConnection } from "./db/db.ts";

// Development mode can be checked via: Deno.env.get("DEVELOPMENT") === "true"

/** Error page HTML for service unavailability */
const SERVICE_UNAVAILABLE_HTML = `<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Service Unavailable</title>
  <link rel="stylesheet" href="/assets/styles.css" />
</head>
<body class="service-unavailable">
  <div class="service-unavailable__container">
    <div class="service-unavailable__icon">🔧</div>
    <h1>The problem is on our side!</h1>
    <p>We will fix this as soon as we can.</p>
  </div>
</body>
</html>`;

/** Check if required KV cache files exist */
function checkKvCacheFiles(): boolean {
  // const requiredFiles = ["./data/kv-cache-shm", "./data/kv-cache-wal"];
  // for (const file of requiredFiles) {
  //   try {
  //     Deno.statSync(file);
  //   } catch {
  //     console.error(`⚠️  Required file missing: ${file}`);
  //     return false;
  //   }
  // }
  return true;
}

/** Perform all startup checks */
async function _performStartupChecks(): Promise<boolean> {
  //console.log("Checking startup requirements...");

  // Check KV cache files
  const kvFilesExist = checkKvCacheFiles();
  if (!kvFilesExist) {
    console.error(
      "⚠️  KV cache files missing - app will display maintenance page",
    );
    return false;
  }
  //console.log("✅ KV cache files found");

  // Check database connection
  //console.log("Checking database connection...");
  const dbAvailable = await checkDatabaseConnection();
  if (!dbAvailable) {
    console.error(
      "⚠️  Database connection failed - app will display maintenance page",
    );
    return false;
  }
  //console.log("✅ Database connection successful");

  return true;
}

// Run startup checks first
const isAppReady = true; // await _performStartupChecks();

// Create app based on startup check result
export const app = new App<State>();

if (isAppReady) {
  // Full app with all routes and middleware
  const { InitiPGSessionMiddleware } = await import(
    "./services/stateMiddleware.ts"
  );
  const { createAuthMiddleware } = await import(
    "./services/authMiddleware.ts"
  );

  app.use(staticFiles());

  app.get("/health", async (_ctx: Context<State>) => {
    console.log("Health check - verifying database connection...");
    const dbConnected = await checkDatabaseConnection();

    if (dbConnected) {
      console.log("✅ Health check: Database connected");
      return new Response(
        JSON.stringify({
          status: "healthy",
          database: "connected",
          timestamp: new Date().toISOString(),
        }),
        {
          status: 200,
          headers: { "Content-Type": "application/json" },
        },
      );
    } else {
      console.log("❌ Health check: Database connection failed");
      return new Response(
        JSON.stringify({
          status: "unhealthy",
          database: "disconnected",
          timestamp: new Date().toISOString(),
        }),
        {
          status: 503,
          headers: { "Content-Type": "application/json" },
        },
      );
    }
  });

  // Debug endpoint to verify database schema (no auth required)
  app.get("/api/debug/schema", async (_ctx: Context<State>) => {
    try {
      const { db } = await import("./db/db.ts");

      // Query PostgreSQL information_schema to get all tables
      const query = `
        SELECT table_name, table_schema
        FROM information_schema.tables
        WHERE table_schema = 'memory'
          OR table_schema = 'checkpoints'
          OR table_schema = 'public'
        ORDER BY table_schema, table_name
      `;

      const result = await db.execute(query);

      // Expected tables based on schema.ts
      const expectedTables = [
        "users",
        "roles",
        "user_roles",
        "state_keys",
        "user_tokens",
        "web_tokens",
        "obligations",
        "incomes",
        "financial_balances",
        "properties",
        "rent_schedules",
        "leases",
        "payment_methods",
        "property_media",
        "lease_documents",
        "tenant_applications",
        "tenant_invites",
        "payment_transactions",
        "reminders",
        "messages",
        "maintenance_requests",
        "user_pins",
        "session_configs",
      ];

      // Extract table names from query result
      const existingTables = result.rows.map((row: Record<string, unknown>) =>
        String(row["table_name"])
      );

      // Find missing tables
      const missingTables = expectedTables.filter(
        (table) => !existingTables.includes(table),
      );

      return new Response(
        JSON.stringify({
          status: "success",
          existing_tables: existingTables,
          expected_tables: expectedTables,
          missing_tables: missingTables,
          all_tables_present: missingTables.length === 0,
          total_existing: existingTables.length,
          total_expected: expectedTables.length,
        }),
        {
          status: 200,
          headers: { "Content-Type": "application/json" },
        },
      );
    } catch (error) {
      console.error("Error checking database schema:", error);
      return new Response(
        JSON.stringify({
          status: "error",
          message: error instanceof Error ? error.message : "Unknown error",
        }),
        {
          status: 500,
          headers: { "Content-Type": "application/json" },
        },
      );
    }
  });

  // Debug endpoint to test session persistence across server restarts
  app.get("/api/debug/persistence-test", async (_ctx: Context<State>) => {
    const url = new URL(_ctx.req.url);
    const action = url.searchParams.get("action") || "check";

    try {
      const { db } = await import("./db/db.ts");
      const TEST_USER_ID = "PERSIST_TEST_12345";
      const TEST_STATE_ID = "test-persist-state-" + Date.now();

      if (action === "create") {
        // Use Drizzle ORM functions for proper database operations
        const { sqlSetStateKey } = await import("./db/sqlUserRepository.ts");

        const createdOn = Date.now();
        const sealKey = "test-seal-key-" + createdOn;

        // Insert test state key using Drizzle ORM
        await sqlSetStateKey(
          sealKey,
          TEST_STATE_ID,
          "test-cookie-hash-" + createdOn,
        );

        // For user_tokens, use raw SQL with schema qualification to avoid drizzle issues
        try {
          await db.execute(sql`
            INSERT INTO memory.user_tokens (user_id, state_id, access_token, refresh_token, created_on, updated_on)
            VALUES (${TEST_USER_ID}, ${TEST_STATE_ID}, ${"test-access-token"}, ${"test-refresh-token"}, ${createdOn}, ${createdOn})
            ON CONFLICT (user_id, state_id)
            DO UPDATE SET
              access_token = EXCLUDED.access_token,
              refresh_token = EXCLUDED.refresh_token,
              updated_on = EXCLUDED.updated_on
          `);
        } catch (tokenError) {
          console.error("Failed to insert user_token:", tokenError);
          // Continue anyway - state_key is the critical test
        }

        return new Response(
          JSON.stringify({
            status: "created",
            message: "Test data created in PostgreSQL",
            test_user_id: TEST_USER_ID,
            test_state_id: TEST_STATE_ID,
            seal_key: sealKey,
            next_step:
              "Restart the server and call with action=verify&state_id=" +
              TEST_STATE_ID,
          }),
          { status: 200, headers: { "Content-Type": "application/json" } },
        );
      }

      if (action === "verify") {
        const stateIdParam = url.searchParams.get("state_id");
        const stateIdToCheck = stateIdParam || TEST_STATE_ID;

        // Use existing SQL repository functions
        const { sqlGetStateKeys, sqlGetUserTokens } = await import(
          "./db/sqlUserRepository.ts"
        );

        const stateKeys = await sqlGetStateKeys(stateIdToCheck);
        const userTokens = await sqlGetUserTokens(TEST_USER_ID);

        const stateKeyExists = stateKeys && stateKeys.length > 0;
        const userTokenExists = userTokens && userTokens.length > 0;

        // State key persistence is the critical test - it's the session data
        // User tokens are secondary
        const persistenceVerified = stateKeyExists;

        return new Response(
          JSON.stringify({
            status: "verified",
            test_user_id: TEST_USER_ID,
            test_state_id: stateIdToCheck,
            state_key_exists: stateKeyExists,
            state_key_data: stateKeyExists ? stateKeys[0] : null,
            user_token_exists: userTokenExists,
            user_token_data: userTokenExists ? userTokens[0] : null,
            persistence_verified: persistenceVerified,
            message: persistenceVerified
              ? "✅ Session state_key PERSISTS across server restart - PostgreSQL is working!"
              : "❌ Session data LOST - using in-memory storage (CRITICAL FAILURE)",
            details: stateKeyExists && !userTokenExists
              ? "State key persisted (primary session data), user token may have had insertion error"
              : null,
            next_step: "Call with action=cleanup&state_id=" + stateIdToCheck +
              " to remove test data",
          }),
          { status: 200, headers: { "Content-Type": "application/json" } },
        );
      }

      if (action === "cleanup") {
        // Remove test data using SQL repository functions
        const { sqlDeleteStateKey, sqlDeleteUserTokens } = await import(
          "./db/sqlUserRepository.ts"
        );

        const stateIdParam = url.searchParams.get("state_id");
        const stateIdToClean = stateIdParam || TEST_STATE_ID;

        // Get the seal key first
        const { sqlGetStateKeys } = await import("./db/sqlUserRepository.ts");
        const stateKeys = await sqlGetStateKeys(stateIdToClean);
        if (stateKeys && stateKeys.length > 0) {
          await sqlDeleteStateKey(stateKeys[0].seal_key);
        }
        await sqlDeleteUserTokens(TEST_USER_ID);

        return new Response(
          JSON.stringify({
            status: "cleaned",
            message: "Test data removed from database",
          }),
          { status: 200, headers: { "Content-Type": "application/json" } },
        );
      }

      // Default: show instructions
      return new Response(
        JSON.stringify({
          status: "ready",
          message: "Persistence test endpoint",
          instructions: [
            "1. Call with action=create to insert test data",
            "2. Restart the Deno server completely",
            "3. Call with action=verify to check if data persisted",
            "4. Call with action=cleanup to remove test data",
          ],
        }),
        { status: 200, headers: { "Content-Type": "application/json" } },
      );
    } catch (error) {
      console.error("Persistence test error:", error);
      return new Response(
        JSON.stringify({
          status: "error",
          message: error instanceof Error ? error.message : "Unknown error",
        }),
        { status: 500, headers: { "Content-Type": "application/json" } },
      );
    }
  });

  // app.post("/graph-update", async (ctx: Context<State>) => {
  //   console.log("Graph update");
  //   const body = await ctx.req.json();
  //   //console.log(body);
  //   //const { userId, roles, organization } = body;

  //   // await inMemoryCacheKv.set(["ciam", userId], {
  //   //   userId,
  //   //   roles,
  //   //   organization,
  //   //   lastSynced: Date.now(),
  //   // });

  //   //console.log(`Graph update applied for user ${userId}`);
  //   return new Response("Graph update stored in cache", { status: 202 });
  // });

  // TODO: add a well-known endpoint
  // app.get("/.well-known/acme-challenge/:token", (ctx: Context<State>) => {
  //   const token = ctx.params.token;
  //   const content = `${token}.EXAMPLE_ACCOUNT_THUMBPRINT`;
  //   return new Response(content, {
  //     status: 200,
  //     headers: {
  //       "content-type": "text/plain; charset=utf-8",
  //       "cache-control": "public, max-age=0, must-revalidate",
  //     },
  //   });
  // });

  app.use(InitiPGSessionMiddleware());
  app.use(createAuthMiddleware());
  app.fsRoutes();

  //console.log("✅ Full application loaded");
} else {
  // Maintenance mode - serve error page for all routes
  app.use(staticFiles());

  app.get("/health", () => {
    return new Response("Service Unavailable", { status: 503 });
  });

  app.use(() => {
    return new Response(SERVICE_UNAVAILABLE_HTML, {
      status: 503,
      headers: { "Content-Type": "text/html; charset=utf-8" },
    });
  });

  console.log("⚠️  Maintenance mode - serving error page only");

  // Start periodic database connection check (every 60 seconds)
  // setInterval(async () => {
  //   console.log("🔄 Checking if database connection is restored...");
  //   const dbAvailable = await checkDatabaseConnection();
  //   if (dbAvailable) {
  //     console.log("✅ Database connection restored! Restarting app...");

  //     // Check if running in development mode

  //     // Use exec to replace shell with new process, keeping terminal connection
  //     const command = new Deno.Command("sh", {
  //       args: [
  //         "-c",
  //         `lsof -ti:8080 | xargs kill -9 2>/dev/null || true; ${restartCmd}`,
  //       ],
  //       cwd: Deno.cwd(),
  //       stdin: "inherit",
  //       stdout: "inherit",
  //       stderr: "inherit",
  //     });
  //     command.spawn();
  //     Deno.exit(0);
  //   } else {
  //     console.log("❌ Database still unavailable, will retry in 60 seconds");
  //   }
  // }, 60_000);
}

// if (import.meta.main) {
//   await app.listen();
// }