import Fluent
import Foundation
import Vapor

func routes(_ app: Application) throws {
  app.get { req in
    let output = try await req.view.render("login")
    return output
  }

  app.get("loggedIn") { req -> View in
    guard let user = try await req.currentUser(withProsAndCons: true) else {
      throw Abort(.badRequest)
    }
    return try await req.view.render(
      "loggedIn",
      LoggedInContext(name: user.displayName, prosAndCons: user.prosAndCons)
    )
  }

  app.get("submitProOrCon") { req in
    let params = try req.query.decode(SubmitProOrCon.self)
    guard let userId = req.userId else {
      throw Abort(.unauthorized)
    }
    try checkForBadWords(in: params.description)
    let proOrCon = ProCon(type: params.type, description: params.description, userId: userId)
    try await proOrCon.save(on: req.db)
    return req.redirect(to: "loggedIn")
  }

  app.get("login") { req in
    let params = try req.query.decode(LoginParams.self)
    req.logger.info("params: \(params)")
    try checkForBadWords(in: params.displayName)
    let user = User(displayName: params.displayName)
    try await user.save(on: req.db)
    req.session.data["userId"] = user.id?.uuidString
    return req.redirect(to: "loggedIn")
  }
}

private extension Request {

  var userId: UUID? {
    guard let userIdString = session.data["userId"],
          let userId = UUID(uuidString: userIdString)
    else {
      return nil
    }
    return userId
  }

  func currentUser(withProsAndCons: Bool) async throws -> User? {
    guard let userId = userId else {
      return nil
    }

    var query = User.query(on: db).filter(\.$id == userId)
    if withProsAndCons {
      query = query.with(\.$prosAndCons)
    }
    return try await query.first()
  }
}

struct DisplayNameError: Error {}

struct LoginParams: Content {
  let displayName: String
}

struct SubmitProOrCon: Content {
  let type: ProCon.ProConType
  let description: String
}

struct LoggedInContext: Encodable {
  let name: String
  let pros: [ProCon]
  let cons: [ProCon]

  init(name: String, prosAndCons: [ProCon]) {
    self.name = name
    self.cons = prosAndCons.filter { $0.type == .con }
    self.pros = prosAndCons.filter { $0.type == .pro }
  }
}