import Vapor

/// Represents a generic form context that is used to generate form templates
/// that are handled by htmx.
struct HtmxFormCTX<Context: Content>: Content {
  let formClass: String?
  let formId: String
  let htmxPostTargetUrl: String?
  let htmxPutTargetUrl: String?
  let htmxTarget: String
  let htmxPushUrl: Bool
  let htmxResetAfterRequest: Bool
  let htmxSwapOob: String?
  let htmxSwap: String?
  let context: Context

  init(
    formClass: String? = nil,
    formId: String,
    htmxTargetUrl: TargetUrl,
    htmxTarget: String,
    htmxPushUrl: Bool,
    htmxResetAfterRequest: Bool = true,
    htmxSwapOob: HtmxSwap? = nil,
    htmxSwap: HtmxSwap? = nil,
    context: Context
  ) {
    self.formClass = formClass
    self.formId = formId
    self.htmxPostTargetUrl = htmxTargetUrl.postUrl
    self.htmxPutTargetUrl = htmxTargetUrl.putUrl
    self.htmxTarget = htmxTarget
    self.htmxPushUrl = htmxPushUrl
    self.htmxResetAfterRequest = htmxResetAfterRequest
    self.htmxSwapOob = htmxSwapOob?.rawValue
    self.htmxSwap = htmxSwap?.rawValue
    self.context = context
  }

  enum HtmxSwap: String {
    case innerHTML
    case outerHTML
    case afterbegin
    case beforebegin
    case afterend
    case beforeend
    case delete
    case none
  }

  enum TargetUrl {
    case put(String)
    case post(String)

    var putUrl: String? {
      guard case let .put(url) = self else { return nil }
      return url
    }

    var postUrl: String? {
      guard case let .post(url) = self else { return nil }
      return url
    }
  }
}

struct EmptyContent: Content {}

struct ButtonLabelContext: Content {
  let buttonLabel: String
}

extension HtmxFormCTX where Context == ButtonLabelContext {
  init(
    formClass: String? = nil,
    formId: String,
    htmxTargetUrl: TargetUrl,
    htmxTarget: String,
    htmxPushUrl: Bool,
    htmxResetAfterRequest: Bool = true,
    htmxSwapOob: HtmxSwap? = nil,
    htmxSwap: HtmxSwap? = nil,
    buttonLabel: String
  ) {
    self.init(
      formClass: formClass,
      formId: formId,
      htmxTargetUrl: htmxTargetUrl,
      htmxTarget: htmxTarget,
      htmxPushUrl: htmxPushUrl,
      htmxResetAfterRequest: htmxResetAfterRequest,
      htmxSwapOob: htmxSwapOob,
      htmxSwap: htmxSwapOob,
      context: .init(buttonLabel: buttonLabel)
    )
  }
}