/**
 * AI 故事分析 Composable
 * 用於分析故事並提取資產
 */

import { useAIProvider } from './useAIProvider'
import { buildStoryAnalysisPrompt, type StoryAnalysisInput } from '~/utils/ai/prompts'
import { getTextModel } from '~/utils/storage'
import { DEFAULT_TEXT_MODEL } from '~/utils/clients/gemini-models'
import { getVisionModel } from '~/utils/storage'
import { DEFAULT_VISION_MODEL } from '~/utils/clients/gemini-models'
import type { StoryAnalysis } from '~/types/storyboard'

export function useAIStoryboardAnalysis() {
  const isLoading = ref(false)
  const error = ref<string | null>(null)

  async function analyze(input: StoryAnalysisInput): Promise<StoryAnalysis> {
    isLoading.value = true
    error.value = null

    try {
      // 如果有圖片，使用視覺模型；否則使用文字模型
      const modelName = input.styleImage 
        ? (getVisionModel() || DEFAULT_VISION_MODEL)
        : (getTextModel() || DEFAULT_TEXT_MODEL)
      const provider = useAIProvider(modelName)
      
      let prompt = buildStoryAnalysisPrompt(input)
      
      // 如果有風格圖片，需要傳遞圖片給 API
      if (input.styleImage) {
        // 這裡需要根據 provider 類型處理圖片
        // 暫時先傳遞文字 prompt，實際實作時需要處理圖片
        const result = await provider.analyzeCamera({
          prompt,
          image: {
            mimeType: 'image/jpeg',
            data: input.styleImage.replace(/^data:image\/\w+;base64,/, '')
          }
        })
        
        // 解析 JSON 結果
        const jsonMatch = result.match(/\{[\s\S]*\}/)
        if (jsonMatch) {
          return JSON.parse(jsonMatch[0]) as StoryAnalysis
        }
        throw new Error('無法解析分析結果')
      } else {
        const result = await provider.generateStoryboard(prompt)
        
        // 解析 JSON 結果
        const jsonMatch = result.match(/\{[\s\S]*\}/)
        if (jsonMatch) {
          return JSON.parse(jsonMatch[0]) as StoryAnalysis
        }
        throw new Error('無法解析分析結果')
      }
    } catch (err) {
      const errorMessage = err instanceof Error ? err.message : '未知錯誤'
      error.value = errorMessage
      throw err
    } finally {
      isLoading.value = false
    }
  }

  return {
    analyze,
    isLoading: readonly(isLoading),
    error: readonly(error)
  }
}