import Elementary
import ElementaryHTMX
import SharedModels

// Form used to login or create a new user.
struct UserForm: HTML, Sendable {
  let context: Context

  var content: some HTML {
    if context.isFloat {
      Float(shouldDisplay: true) {
        makeForm()
      }
    } else {
      makeForm()
    }
  }

  private func makeForm() -> some HTML {
    form(
      .id(.user(.form)),
      .class("user-form"),
      context.isResetPassword ? .hx.patch(route: context.targetURL) : .hx.post(route: context.targetURL),
      .hx.pushURL(context.pushURL),
      .hx.target(context.target),
      .hx.swap(context == .create ? .afterBegin.transition(true).swap("0.5s") : .outerHTML),
      .hx.on(
        .afterRequest,
        context.toggleContent ? .ifSuccessful(.resetForm, .toggleContent(.float)) : .ifSuccessful(.resetForm)
      )
    ) {
      if case let .login(next) = context, let next {
        input(.type(.hidden), .name("next"), .value(next))
      }
      if context.showUsername {
        div(.class("row")) {
          input(.type(.text), .id("username"), .name("username"), .placeholder("Username"), .autofocus, .required)
        }
      }
      if context.showEmailInput {
        div(.class("row")) {
          input(.type(.email), .id("email"), .name("email"), .placeholder("Email"), .required)
        }
      }
      div(.class("row")) {
        input(.type(.password), .id("password"), .name("password"), .placeholder("Password"), .required)
      }
      if context.showConfirmPassword {
        div(.class("row")) {
          input(
            .type(.password), .id("confirmPassword"), .name("confirmPassword"),
            .placeholder("Confirm Password"),
            .required
          )
        }
      }
      div(.class("row")) {
        button(.type(.submit), .class("btn-primary")) { context.buttonLabel }
      }
    }
  }

  enum Context: Equatable, Sendable {
    case create
    case login(next: String?)
    case resetPassword(id: User.ID)

    var isResetPassword: Bool {
      guard case .resetPassword = self else { return false }
      return true
    }

    var isFloat: Bool {
      switch self {
      case .create,
           .resetPassword:
        return true
      case .login:
        return false
      }
    }

    var toggleContent: Bool {
      guard case .resetPassword = self else { return true }
      return false
    }

    var showUsername: Bool {
      switch self {
      case .create: return true
      case .login: return true
      case .resetPassword: return false
      }
    }

    var showConfirmPassword: Bool {
      switch self {
      case .create: return true
      case .login: return false
      case .resetPassword: return true
      }
    }

    var showEmailInput: Bool {
      switch self {
      case .create: return true
      case .login: return false
      case .resetPassword: return false
      }
    }

    var pushURL: Bool {
      switch self {
      case .create: return false
      case .login: return true
      case .resetPassword: return false
      }
    }

    var buttonLabel: String {
      switch self {
      case .create:
        return "Create"
      case .login:
        return "Login"
      case .resetPassword:
        return "Reset"
      }
    }

    var target: HXTarget {
      switch self {
      case .create:
        return .id(.user(.table))
      case .login:
        return .body
      case .resetPassword:
        return .id(.float)
      }
    }

    var targetURL: SiteRoute.View {
      switch self {
      case .create:
        return .user(.index)
      case .login:
        return .login(.index())
      case let .resetPassword(id: id):
        return .resetPassword(.index(id: id))
      }
    }
  }
}