const express = require("express");
const cors = require("cors");
const helmet = require("helmet");
const fs = require("fs").promises;
const path = require("path");
require("dotenv").config();

const app = express();
const PORT = process.env.PORT || 3001;

app.use(helmet());
app.use(
  cors({
    origin: process.env.ALLOWED_ORIGINS?.split(",") || [
      "http://localhost:3000",
    ],
    credentials: true,
  }),
);
app.use(express.json());

const authenticateAdmin = (req, res, next) => {
  const adminPassword = req.headers.authorization?.replace("Bearer ", "");
  if (adminPassword !== process.env.ADMIN_PASSWORD) {
    return res.status(401).json({ error: "Unauthorized" });
  }
  next();
};

const DISCOUNT_CODES_PATH = path.join(__dirname, "data", "discountCodes.json");
const PRODUCTS_PATH = path.join(__dirname, "data", "products.js");

let cache = {
  discountCodes: null,
  products: null,
  lastUpdated: {
    discountCodes: null,
    products: null,
  },
};

const clearCache = () => {
  cache.discountCodes = null;
  cache.products = null;
  cache.lastUpdated.discountCodes = null;
  cache.lastUpdated.products = null;
};

const readDiscountCodes = async () => {
  try {
    const data = await fs.readFile(DISCOUNT_CODES_PATH, "utf8");
    return JSON.parse(data);
  } catch (error) {
    console.error("Error reading discount codes:", error);
    return {};
  }
};

const writeDiscountCodes = async (codes) => {
  try {
    await fs.writeFile(
      DISCOUNT_CODES_PATH,
      JSON.stringify(codes, null, 2),
      "utf8",
    );
    return true;
  } catch (error) {
    console.error("Error writing discount codes:", error);
    return false;
  }
};

const readProducts = async () => {
  try {
    const data = await fs.readFile(PRODUCTS_PATH, "utf8");
    const match = data.match(
      /export const products: Product\[\] = (\[[\s\S]*?\]);/,
    );
    if (match) {
      const productsString = match[1]
        .replace(/(\w+):/g, '"$1":')
        .replace(/'/g, '"')
        .replace(/,\s*}/g, "}")
        .replace(/,\s*]/g, "]");

      return JSON.parse(productsString);
    }
    return [];
  } catch (error) {
    console.error("Error reading products:", error);
    return [];
  }
};

const writeProducts = async (products) => {
  try {
    const jsContent = `import type { Product } from "../types/product";

export const products: Product[] = ${JSON.stringify(products, null, 2)
        .replace(/"([^"]+)":/g, "$1:")
        .replace(/"/g, '"')};
`;
    await fs.writeFile(PRODUCTS_PATH, jsContent, "utf8");
    return true;
  } catch (error) {
    console.error("Error writing products:", error);
    return false;
  }
};


app.get("/health", (req, res) => {
  res.json({ status: "ok", timestamp: new Date().toISOString() });
});

app.get("/api/discount-codes", async (req, res) => {
  try {
    if (!cache.discountCodes) {
      console.log("Loading discount codes from file...");
      cache.discountCodes = await readDiscountCodes();
      cache.lastUpdated.discountCodes = new Date();
    }

    res.json(cache.discountCodes);
  } catch (error) {
    console.error("Error getting discount codes:", error);
    res.status(500).json({ error: "Failed to get discount codes" });
  }
});

app.post("/api/discount-codes", authenticateAdmin, async (req, res) => {
  try {
    const { code, percentage, expiration, description } = req.body;

    if (!code || !percentage) {
      return res
        .status(400)
        .json({ error: "Code and percentage are required" });
    }

    const discountCodes = await readDiscountCodes();

    const newCode = {
      percentage: parseInt(percentage),
      description: description || "",
    };

    if (expiration) {
      newCode.expiration = expiration;
    }

    discountCodes[code] = newCode;

    const success = await writeDiscountCodes(discountCodes);
    if (!success) {
      return res.status(500).json({ error: "Failed to save discount code" });
    }

    clearCache();

    res.json({ success: true, code: newCode });
  } catch (error) {
    console.error("Error adding discount code:", error);
    res.status(500).json({ error: "Failed to add discount code" });
  }
});

app.delete("/api/discount-codes/:code", authenticateAdmin, async (req, res) => {
  try {
    const { code } = req.params;

    const discountCodes = await readDiscountCodes();

    if (!discountCodes[code]) {
      return res.status(404).json({ error: "Discount code not found" });
    }

    delete discountCodes[code];

    const success = await writeDiscountCodes(discountCodes);
    if (!success) {
      return res.status(500).json({ error: "Failed to delete discount code" });
    }

    clearCache();

    res.json({ success: true });
  } catch (error) {
    console.error("Error deleting discount code:", error);
    res.status(500).json({ error: "Failed to delete discount code" });
  }
});

app.get("/api/products", async (req, res) => {
  try {
    if (!cache.products) {
      console.log("Loading products from file...");
      cache.products = await readProducts();
      cache.lastUpdated.products = new Date();
    }

    res.json(cache.products);
  } catch (error) {
    console.error("Error getting products:", error);
    res.status(500).json({ error: "Failed to get products" });
  }
});

app.put("/api/products/:productId", authenticateAdmin, async (req, res) => {
  try {
    const { productId } = req.params;
    const { pricePerStack } = req.body;

    if (pricePerStack === undefined) {
      return res.status(400).json({ error: "pricePerStack is required" });
    }

    const products = await readProducts();
    const productIndex = products.findIndex((p) => p.id === productId);

    if (productIndex === -1) {
      return res.status(404).json({ error: "Product not found" });
    }

    products[productIndex].pricePerStack = parseFloat(pricePerStack);

    const success = await writeProducts(products);
    if (!success) {
      return res.status(500).json({ error: "Failed to update product" });
    }

    clearCache();

    res.json({ success: true, product: products[productIndex] });
  } catch (error) {
    console.error("Error updating product:", error);
    res.status(500).json({ error: "Failed to update product" });
  }
});

app.get("/api/cache-status", (req, res) => {
  res.json({
    cache: {
      discountCodes: {
        cached: !!cache.discountCodes,
        lastUpdated: cache.lastUpdated.discountCodes,
      },
      products: {
        cached: !!cache.products,
        lastUpdated: cache.lastUpdated.products,
      },
    },
  });
});

app.post("/api/clear-cache", authenticateAdmin, (req, res) => {
  clearCache();
  res.json({ success: true, message: "Cache cleared" });
});

app.use((error, req, res, next) => {
  console.error("Unhandled error:", error);
  res.status(500).json({ error: "Internal server error" });
});

app.use((req, res) => {
  res.status(404).json({ error: "Not found" });
});

const initializeDataDirectory = async () => {
  const dataDir = path.join(__dirname, "data");
  try {
    await fs.access(dataDir);
  } catch {
    await fs.mkdir(dataDir, { recursive: true });

    try {
      await fs.access(DISCOUNT_CODES_PATH);
    } catch {
      await fs.writeFile(DISCOUNT_CODES_PATH, "{}", "utf8");
    }

    try {
      await fs.access(PRODUCTS_PATH);
    } catch {
      const initialProducts = `import type { Product } from "../types/product";

export const products: Product[] = [
  {
    id: "spruce-log",
    name: "Spruce Log",
    pricePerStack: 1,
  },
  {
    id: "birch-log",
    name: "Birch Log",
    pricePerStack: 1,
  },
  {
    id: "oak-log",
    name: "Oak Log",
    pricePerStack: 1,
  },
  {
    id: "jungle-log",
    name: "Jungle Log",
    pricePerStack: 1,
  },
  {
    id: "cobblestone",
    name: "Cobblestone",
    pricePerStack: 1 / 16,
    defaultStacksPerDia: 16,
    variants: ["Cobblestone", "Stone", "Stone Bricks"],
  },
  {
    id: "sand",
    name: "Sand",
    pricePerStack: 1,
  },
  {
    id: "gunpowder",
    name: "Gunpowder",
    pricePerStack: 1 / 4,
    defaultStacksPerDia: 4,
  },
];
`;
      await fs.writeFile(PRODUCTS_PATH, initialProducts, "utf8");
    }
  }
};

const startServer = async () => {
  try {
    await initializeDataDirectory();

    app.listen(PORT, () => {
      console.log(`🚀 Data server running on port ${PORT}`);
      console.log(`📂 Discount codes: ${DISCOUNT_CODES_PATH}`);
      console.log(`📂 Products: ${PRODUCTS_PATH}`);
      console.log(
        `🔐 Admin password: ${process.env.ADMIN_PASSWORD ? "Set" : "Not set"}`,
      );
    });
  } catch (error) {
    console.error("Failed to start server:", error);
    process.exit(1);
  }
};

startServer();