import Dependencies
import Fluent
import Vapor

struct UserViewController: RouteCollection {

  @Dependency(\.users) var users

  private let api = UserApiController()

  func boot(routes: any RoutesBuilder) throws {
    let users = routes.protected.grouped("users")
    users.get(use: index(req:))
    users.post(use: create(req:))
    users.group(":id") {
      $0.get(use: details(req:))
      $0.delete(use: delete(req:))
    }
  }

  @Sendable
  func index(req: Request) async throws -> View {
    try await renderIndex(req)
  }

  @Sendable
  private func renderIndex(_ req: Request, _ user: User.DTO? = nil) async throws -> View {
    let users = try await api.getSortedUsers(req: req)
    return try await req.view.render("users/index", UsersCTX(user: user, users: users))
  }

  @Sendable
  func create(req: Request) async throws -> View {
    let user = try await api.create(req: req)
    return try await req.view.render("users/table-row", user)
  }

  @Sendable
  func details(req: Request) async throws -> View {
    let user = try await users.get(req.ensureIDPathComponent())
    // Check if the page has been rendered before.
    guard req.isHtmxRequest else {
      // Not an htmx-request, so render the whole page with the details.
      return try await renderIndex(req, user)
    }
    // An htmx-request header was present, so just return the details,
    return try await req.view.render("users/detail", ["user": user])
  }

  @Sendable
  func delete(req: Request) async throws -> View {
    _ = try await api.delete(req: req)
    return try await req.view.render("users/table", ["users": api.getSortedUsers(req: req)])
  }
}

struct UserFormCTX: Content {
  let htmxForm: HtmxFormCTX<Context>

  struct Context: Content {
    let showConfirmPassword: Bool
    let showEmailInput: Bool
    let buttonLabel: String
  }

  static func signIn(next: String?) -> Self {
    .init(
      htmxForm: .init(
        formClass: "user-form",
        formId: "user-form",
        htmxTargetUrl: .post("/login\((next != nil && next != "/") ? "?next=\(next!)" : "")"),
        htmxTarget: "user-table",
        htmxPushUrl: true,
        htmxResetAfterRequest: true,
        htmxSwapOob: nil,
        htmxSwap: .afterbegin,
        context: .init(showConfirmPassword: false, showEmailInput: false, buttonLabel: "Sign In")
      )
    )
  }

  static func create() -> Self {
    .init(
      htmxForm: .init(
        formClass: "user-form",
        formId: "user-form",
        htmxTargetUrl: .post("/users"),
        htmxTarget: "#user-table",
        htmxPushUrl: false,
        htmxResetAfterRequest: true,
        htmxSwapOob: nil,
        htmxSwap: nil,
        context: .init(showConfirmPassword: true, showEmailInput: true, buttonLabel: "Create")
      )
    )
  }
}

private struct UsersCTX: Content {
  let user: User.DTO?
  let users: [User.DTO]
  let form: UserFormCTX

  init(
    user: User.DTO? = nil,
    users: [User.DTO],
    form: UserFormCTX? = nil
  ) {
    self.user = user
    self.users = users
    self.form = form ?? .create()
  }
}

private extension UserApiController {

  func getSortedUsers(req: Request) async throws -> [User.DTO] {
    try await index(req: req)
      .sorted { ($0.username ?? "") < ($1.username ?? "") }
  }
}