import Vapor
import Foundation
import FoundationNetworking
import Crypto
import Leaf

func routes(_ app: Application) throws {
    // Render home page when root domain is loaded
    app.get { req  -> EventLoopFuture<View> in
        // Get data from config file at /Resources/config.json
        let fileData = try String(contentsOfFile: "\(app.directory.resourcesDirectory)/config.json").data(using: .utf8)
        // Decode JSON file to Config struct
        let config: Config = try! JSONDecoder().decode(Config.self, from: fileData!)
        // Check if user is logged in
        let loginStatus = req.session.data["loggedIn"] ?? "false"
        // Change loginStatus to a boolean
        let loginBool = loginStatus == "true" ? true : false
        // Render home.leaf with config and login status as context
        return req.view.render("home", LContext(config: config, loggedIn: loginBool))
    }

    // Return website status when /status/:url is loaded
    app.get("status", ":url") { req -> [String: String] in
        // Get URL from request parameters
        let url = URL(string: "http://\(req.parameters.get("url")!)")
        // Configure URLSession
        let config = URLSessionConfiguration.default
        // Set request timeouts to 5s, then assume offline
        config.timeoutIntervalForRequest = 5
        config.timeoutIntervalForResource = 5
        // Declare statusDict for storing website status
        var statusDict: [String:String] = [:]
        // Declare URLSession request using URL from request parameters
        var headReq = URLRequest(url: url!)
        // Set HEAD request
        headReq.httpMethod = "HEAD"
        // Set request timeout to 5s, then assume offline
        headReq.timeoutInterval = 5
        // Create DispatchSemaphore to block thread until request is resolved and status stored
        let semaphore = DispatchSemaphore(value: 0)
        // Run Async URLSession dataTask
        URLSession.shared.dataTask(with: headReq, completionHandler:  { (_, response, error) in
            // If the response is valid
            if let httpURLResponse = response as? HTTPURLResponse {
                // Store status code in statusDict
                statusDict["code"] = String(httpURLResponse.statusCode)
                // Store website status in statusDict
                statusDict["down"] = "false"
            }
            // Signal DispatchSemaphore to stop blocking
            semaphore.signal()
        }).resume()
        // Wait for semaphore signal
        semaphore.wait()
        // If statusDict is empty, return code 0, down true. Otherwise, return statusdict
        return statusDict.count > 0 ? statusDict : ["code": "0", "down": "true"]
    }

    // Render login page on GET request to /login
    app.get("login") { req -> EventLoopFuture<View> in
        // Get data from config file at /Resources/config.json
        let fileData = try String(contentsOfFile: "\(app.directory.resourcesDirectory)/config.json").data(using: .utf8)
        // Decode JSON file to Config struct
        let config: Config = try! JSONDecoder().decode(Config.self, from: fileData!)
        // Render home.leaf with config as context
        return req.view.render("login", LContext(config: config, loggedIn: false))
    }

    // Verify credentials and log in on POST request to /login
    app.post("login") { req -> Response in
        // Decode POST request data into Login struct
        let data = try req.content.decode(Login.self)
        // Get data from config file at /Resources/config.json
        let fileData = try String(contentsOfFile: "\(app.directory.resourcesDirectory)/config.json").data(using: .utf8)
        // Decode JSON file to Config struct
        let config: Config = try! JSONDecoder().decode(Config.self, from: fileData!)
        // Get password from POST request data
        let loginPassData = data.password?.data(using: .utf8)
        // Hash password in POST data using SHA256.hash() from SwiftCrypto
        let loginPassHash = SHA256.hash(data: loginPassData ?? "".data(using: .utf8)!)
        // Convert hash to string
        let stringHash = loginPassHash.map { String(format: "%02hhx", $0) }.joined()
        // If hash in config matches provided hash
        if stringHash == config.passwordHash {
            // Set logged in to true in session
            req.session.data["loggedIn"] = "true"
            // Redirect back to /
            return try req.redirect(to: "/")
        } else {
            // If hashes do not match, return unauthorized error
            throw Abort(.unauthorized)
        }
    }

    // Destroy session on GET request to logout
    app.get("logout") { req -> Response in
        // Destroy session
        req.session.destroy()
        // Redirect back to /
        return try req.redirect(to: "/")
    }


}