import { BelongsTo, Column, DataType, ForeignKey, Model, PrimaryKey, Table } from 'sequelize-typescript';
import { AiConversation } from './ai-conversation.model';

export enum RoleType {
  System = 'system',
  User = 'user',
  Assistant = 'assistant',
}

@Table({
  tableName: 't_ai_messages',
  underscored: true,
})
export class AiMessage extends Model {
  @PrimaryKey
  @Column({
    type: DataType.BIGINT,
    autoIncrement: true,
  })
  declare id: number;

  @ForeignKey(() => AiConversation)
  @Column({
    type: DataType.STRING,
    allowNull: false,
    comment: '会话ID',
  })
  declare conversationId: string;

  @Column({
    type: DataType.STRING,
    allowNull: false,
    comment: '用户ID',
  })
  declare userId: string;

  @Column({
    type: DataType.ENUM('system', 'user', 'assistant'),
    allowNull: false,
  })
  declare role: RoleType;

  @Column({
    type: DataType.TEXT('long'),
    allowNull: false,
  })
  declare content: string;

  @Column({
    type: DataType.JSON,
    allowNull: true,
    comment: '扩展元数据，如token用量、模型名等',
  })
  declare metadata: Record<string, any> | null;

  @Column({
    type: DataType.DATE,
    defaultValue: DataType.NOW,
  })
  declare createdAt: Date;

  @Column({
    type: DataType.DATE,
    defaultValue: DataType.NOW,
  })
  declare updatedAt: Date;

  @BelongsTo(() => AiConversation)
  declare conversation?: AiConversation;
}