import { createAnthropic } from '@ai-sdk/anthropic';
import { generateObject, generateText as aiGenerateText, stepCountIs } from 'ai';
import { z } from 'zod';
import { AIProvider, TagSuggestion, TitleSuggestion, ToolUseOptions, ToolCallResult } from '../types';

export class AnthropicProvider implements AIProvider {
  private model: any;

  /**
   * @param baseURL Optional Messages API root (no trailing slash). The SDK calls `{baseURL}/messages`.
   *   MiniMax: `https://api.minimax.io/anthropic` (China: `https://api.minimaxi.com/anthropic`).
   */
  constructor(apiKey: string, modelName: string = 'claude-sonnet-4-20250514', baseURL?: string) {
    const trimmedBase = baseURL?.trim().replace(/\/+$/, '');
    const anthropicClient = createAnthropic(trimmedBase ? { apiKey, baseURL: trimmedBase } : { apiKey });
    this.model = anthropicClient.chat(modelName);
  }

  async generateTags(content: string): Promise<TagSuggestion[]> {
    try {
      const { object } = await generateObject({
        model: this.model,
        schema: z.object({
          tags: z.array(z.object({
            tag: z.string().describe('Short tag name in lowercase'),
            confidence: z.number().min(0).max(1).describe('Confidence level between 0 and 1'),
          })),
        }),
        prompt: `Analyze the following note and suggest 1 to 5 relevant tags.
        Note content: "${content}"`,
      });

      return object.tags;
    } catch (e) {
      console.error('Error generating tags (Anthropic):', e);
      return [];
    }
  }

  async getEmbeddings(_text: string): Promise<number[]> {
    throw new Error(
      'Anthropic does not expose embedding models in Memento. Choose another provider for embeddings (e.g. Ollama or OpenAI).'
    );
  }

  async generateTitles(prompt: string): Promise<TitleSuggestion[]> {
    try {
      const { object } = await generateObject({
        model: this.model,
        schema: z.object({
          titles: z.array(z.object({
            title: z.string().describe('Suggested title'),
            confidence: z.number().min(0).max(1).describe('Confidence level between 0 and 1'),
          })),
        }),
        prompt,
      });

      return object.titles;
    } catch (e) {
      console.error('Error generating titles (Anthropic):', e);
      return [];
    }
  }

  async generateText(prompt: string): Promise<string> {
    try {
      const { text } = await aiGenerateText({
        model: this.model,
        prompt,
      });

      return text.trim();
    } catch (e) {
      console.error('Error generating text (Anthropic):', e);
      throw e;
    }
  }

  async chat(messages: any[], systemPrompt?: string): Promise<any> {
    try {
      const { text } = await aiGenerateText({
        model: this.model,
        system: systemPrompt,
        messages,
      });

      return { text: text.trim() };
    } catch (e) {
      console.error('Error in chat (Anthropic):', e);
      throw e;
    }
  }

  async generateWithTools(options: ToolUseOptions): Promise<ToolCallResult> {
    const { tools, maxSteps = 10, systemPrompt, messages, prompt } = options;
    const opts: Record<string, any> = {
      model: this.model,
      tools,
      stopWhen: stepCountIs(maxSteps),
    };
    if (systemPrompt) opts.system = systemPrompt;
    if (messages) opts.messages = messages;
    else if (prompt) opts.prompt = prompt;

    const result = await aiGenerateText(opts as any);
    return {
      toolCalls: result.toolCalls?.map((tc: any) => ({ toolName: tc.toolName, input: tc.input })) || [],
      toolResults: result.toolResults?.map((tr: any) => ({ toolName: tr.toolName, input: tr.input, output: tr.output })) || [],
      text: result.text,
      steps: result.steps?.map((step: any) => ({
        text: step.text,
        toolCalls: step.toolCalls?.map((tc: any) => ({ toolName: tc.toolName, input: tc.input })) || [],
        toolResults: step.toolResults?.map((tr: any) => ({ toolName: tr.toolName, input: tr.input, output: tr.output })) || [],
      })) || [],
    };
  }

  getModel() {
    return this.model;
  }
}