// Copyright 2025 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//      http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

import Foundation

@available(iOS 15.0, macOS 12.0, macCatalyst 15.0, tvOS 15.0, watchOS 8.0, *)
struct TemplateGenerateContentRequest: Sendable {
  let template: String
  let variables: [String: TemplateVariable]
  let history: [ModelContent]
  let projectID: String
  let stream: Bool

  let apiConfig: APIConfig
  let options: RequestOptions
}

@available(iOS 15.0, macOS 12.0, macCatalyst 15.0, tvOS 15.0, watchOS 8.0, *)
extension TemplateGenerateContentRequest: Encodable {
  enum CodingKeys: String, CodingKey {
    case variables = "inputs"
    case history
  }

  func encode(to encoder: any Encoder) throws {
    var container = encoder.container(keyedBy: CodingKeys.self)
    try container.encode(variables, forKey: .variables)
    try container.encode(history, forKey: .history)
  }
}

@available(iOS 15.0, macOS 12.0, macCatalyst 15.0, tvOS 15.0, watchOS 8.0, *)
extension TemplateGenerateContentRequest: GenerativeAIRequest {
  typealias Response = GenerateContentResponse

  var url: URL {
    var urlString =
      "\(apiConfig.service.endpoint.rawValue)/\(apiConfig.version.rawValue)/projects/\(projectID)"
    if case let .vertexAI(_, location) = apiConfig.service {
      urlString += "/locations/\(location)"
    }
    let templateName = template.hasSuffix(".prompt") ? template : "\(template).prompt"
    urlString += "/templates/\(templateName):templateGenerateContent"
    if stream {
      // TODO: Fix this.
      urlString += "?alt=sse"
    }
    return URL(string: urlString)!
  }
}