/// 上传域模型（P3 计划 Task 2）：直传会话、凭证与请求体。
///
/// 契约来源：`packages/contracts/openapi.yaml` tag `uploads`。
library;

import '../photos/models.dart';

/// 上传会话状态（服务端视角；本地任务状态机见技术实施方案 §5.5、
/// P3 计划 Task 5）。
///
/// 契约 `components.schemas.UploadSessionState`：会话没有 failed 状态——
/// 完成核验失败属于单次请求错误（UPLOAD_VERIFY_FAILED），会话保持
/// pending 可重试。
enum UploadSessionState {
  pending('pending'),
  confirmed('confirmed'),
  cancelled('cancelled'),
  expired('expired');

  const UploadSessionState(this.wire);

  /// 线上（JSON）取值。
  final String wire;

  static UploadSessionState fromJson(String value) => values.firstWhere(
        (v) => v.wire == value,
        orElse: () => throw FormatException('未知 UploadSessionState: $value'),
      );
}

/// staging 对象的临时直传凭证。
///
/// 契约 `components.schemas.UploadCredential`：仅可写入指定 objectKey，
/// 不可访问 originals/variants；过期后续签（renew）再重试。
class UploadCredential {
  const UploadCredential({
    required this.mode,
    required this.url,
    required this.method,
    required this.headers,
    required this.expiresAt,
  });

  factory UploadCredential.fromJson(Map<String, dynamic> json) =>
      UploadCredential(
        mode: json['mode'] as String,
        url: json['url'] as String,
        method: json['method'] as String,
        headers: (json['headers'] as Map<dynamic, dynamic>)
            .map((dynamic k, dynamic v) => MapEntry(k as String, v as String)),
        expiresAt: DateTime.parse(json['expiresAt'] as String),
      );

  /// 凭证模式；P1a 仅 presigned，预留 STS 扩展。
  final String mode;

  /// 预签名上传 URL。
  final String url;

  /// 上传 HTTP 方法（PUT）。
  final String method;

  /// 上传时必须携带的请求头（如 Content-Type）。
  final Map<String, String> headers;

  /// 凭证过期时间。
  final DateTime expiresAt;

  Map<String, dynamic> toJson() => {
        'mode': mode,
        'url': url,
        'method': method,
        'headers': headers,
        'expiresAt': expiresAt.toUtc().toIso8601String(),
      };
}

/// 初始化上传任务请求体。
///
/// 契约 `components.schemas.UploadInitRequest`（operationId
/// `initUpload`，POST /uploads）：幂等初始化——相同 clientTaskId 且参数
/// 一致时返回原会话，参数不一致 409（UPLOAD_SESSION_CONFLICT）。
///
/// sourceDeviceId 为 P3 Task 3 契约增补（已落地）：客户端首次生成并
/// 持久的设备标识（A19 设备来源语义，见 core/device_id.dart）；可选，
/// 同一 clientTaskId 幂等重放时服务端保留首次落库的值。
class UploadInitRequest {
  const UploadInitRequest({
    required this.albumId,
    required this.clientTaskId,
    required this.filename,
    required this.bytes,
    required this.contentType,
    this.categoryId,
    this.sourceDeviceId,
  });

  /// 目标相册 ID。
  final String albumId;

  /// 目标分类 ID；缺省为相册默认分类。
  final String? categoryId;

  /// 客户端任务幂等键；同一任务的重试必须复用（maxLength 128）。
  final String clientTaskId;

  /// 原始文件名（仅元数据，maxLength 255）。
  final String filename;

  /// 申明文件字节数；完成核验时逐一比对。
  final int bytes;

  /// MIME 类型（白名单 image/jpeg | image/png | image/heic）。
  final String contentType;

  /// 发起设备标识（可选，minLength 8 / maxLength 64；A19）。
  final String? sourceDeviceId;

  Map<String, dynamic> toJson() => {
        'albumId': albumId,
        if (categoryId != null) 'categoryId': categoryId,
        'clientTaskId': clientTaskId,
        'filename': filename,
        'bytes': bytes,
        'contentType': contentType,
        if (sourceDeviceId != null) 'sourceDeviceId': sourceDeviceId,
      };
}

/// 初始化上传任务响应。
///
/// 契约 `components.schemas.UploadInitResponse`（operationId `initUpload`
/// → 201；`renewUploadCredential` → 200 结构相同，credential 为新值、
/// 其余字段回显原会话）。
class UploadInitResponse {
  const UploadInitResponse({
    required this.uploadId,
    required this.photoId,
    required this.objectKey,
    required this.credential,
  });

  factory UploadInitResponse.fromJson(Map<String, dynamic> json) =>
      UploadInitResponse(
        uploadId: json['uploadId'] as String,
        photoId: json['photoId'] as String,
        objectKey: json['objectKey'] as String,
        credential: UploadCredential.fromJson(
          json['credential'] as Map<String, dynamic>,
        ),
      );

  /// 上传会话 ID。
  final String uploadId;

  /// 预创建的照片 ID（重试复用，不重复建照片）。
  final String photoId;

  /// staging 对象键
  /// （photo-live/{env}/staging/{uploadId}/{photoId}.{ext}）。
  final String objectKey;

  /// staging 对象的临时直传凭证。
  final UploadCredential credential;

  Map<String, dynamic> toJson() => {
        'uploadId': uploadId,
        'photoId': photoId,
        'objectKey': objectKey,
        'credential': credential.toJson(),
      };
}

/// 完成核验响应。
///
/// 契约 `components.schemas.UploadCompleteResponse`（operationId
/// `completeUpload`，POST /uploads/{uploadId}/complete → 200；幂等）。
class UploadCompleteResponse {
  const UploadCompleteResponse({
    required this.photoId,
    required this.processingState,
  });

  factory UploadCompleteResponse.fromJson(Map<String, dynamic> json) =>
      UploadCompleteResponse(
        photoId: json['photoId'] as String,
        processingState:
            PhotoProcessingState.fromJson(json['processingState'] as String),
      );

  /// 照片 ID。
  final String photoId;

  /// 核验通过后的处理状态（进入处理流水线）。
  final PhotoProcessingState processingState;

  Map<String, dynamic> toJson() => {
        'photoId': photoId,
        'processingState': processingState.wire,
      };
}

/// 会话关联照片的当前状态（会话记录内嵌，客户端据此展示服务端进度）。
///
/// 契约 `components.schemas.UploadSessionPhoto`。
class UploadSessionPhoto {
  const UploadSessionPhoto({
    required this.photoId,
    required this.processingState,
    required this.visibility,
  });

  factory UploadSessionPhoto.fromJson(Map<String, dynamic> json) =>
      UploadSessionPhoto(
        photoId: json['photoId'] as String,
        processingState:
            PhotoProcessingState.fromJson(json['processingState'] as String),
        visibility: PhotoVisibility.fromJson(json['visibility'] as String),
      );

  /// 照片 ID。
  final String photoId;

  /// 服务端处理状态。
  final PhotoProcessingState processingState;

  /// 对外可见性。
  final PhotoVisibility visibility;

  Map<String, dynamic> toJson() => {
        'photoId': photoId,
        'processingState': processingState.wire,
        'visibility': visibility.wire,
      };
}

/// 上传会话记录。
///
/// 契约 `components.schemas.UploadSessionRecord`（GET /uploads，
/// operationId `listUploads` 的条目）：当前用户的上传会话历史（新在前），
/// 用于任务队列恢复与跨设备状态展示（A19）。
class UploadSessionRecord {
  const UploadSessionRecord({
    required this.uploadId,
    required this.albumId,
    required this.clientTaskId,
    required this.state,
    required this.expectedBytes,
    required this.contentType,
    required this.createdAt,
    required this.photo,
    this.sourceDeviceId,
  });

  factory UploadSessionRecord.fromJson(Map<String, dynamic> json) =>
      UploadSessionRecord(
        uploadId: json['uploadId'] as String,
        albumId: json['albumId'] as String,
        clientTaskId: json['clientTaskId'] as String,
        state: UploadSessionState.fromJson(json['state'] as String),
        expectedBytes: json['expectedBytes'] as int,
        contentType: json['contentType'] as String,
        createdAt: DateTime.parse(json['createdAt'] as String),
        photo: UploadSessionPhoto.fromJson(
          json['photo'] as Map<String, dynamic>,
        ),
        sourceDeviceId: json['sourceDeviceId'] as String?,
      );

  /// 上传会话 ID。
  final String uploadId;

  /// 目标相册 ID。
  final String albumId;

  /// 客户端任务幂等键。
  final String clientTaskId;

  /// 会话状态。
  final UploadSessionState state;

  /// 申明文件字节数。
  final int expectedBytes;

  /// 申明 MIME 类型。
  final String contentType;

  /// 会话创建时间。
  final DateTime createdAt;

  /// 发起设备标识（init 时未携带为 null；P3 Task 3 契约增补，A19）。
  final String? sourceDeviceId;

  /// 会话关联照片的当前状态。
  final UploadSessionPhoto photo;

  Map<String, dynamic> toJson() => {
        'uploadId': uploadId,
        'albumId': albumId,
        'clientTaskId': clientTaskId,
        'state': state.wire,
        'expectedBytes': expectedBytes,
        'contentType': contentType,
        'createdAt': createdAt.toUtc().toIso8601String(),
        if (sourceDeviceId != null) 'sourceDeviceId': sourceDeviceId,
        'photo': photo.toJson(),
      };
}