'use server'

interface OpenAIModel {
  id: string
  object: string
  created?: number
  owned_by?: string
}

interface OpenAIModelsResponse {
  object: string
  data: OpenAIModel[]
}

async function fetchModelsFromEndpoint(
  endpoint: string,
  apiKey?: string
): Promise<{ success: boolean; models: string[]; error?: string }> {
  try {
    const headers: Record<string, string> = {
      'Content-Type': 'application/json',
    }
    if (apiKey) {
      headers['Authorization'] = `Bearer ${apiKey}`
    }

    const response = await fetch(endpoint, {
      method: 'GET',
      headers,
      signal: AbortSignal.timeout(8000),
    })

    if (!response.ok) {
      throw new Error(`API returned ${response.status}: ${response.statusText}`)
    }

    const data = await response.json() as OpenAIModelsResponse

    const modelIds = (data.data || [])
      .map((m) => m.id)
      .filter(Boolean)
      .sort()

    return { success: true, models: modelIds }
  } catch (error: any) {
    console.error('Failed to fetch provider models:', error)
    return {
      success: false,
      models: [],
      error: error.message || 'Failed to connect to provider',
    }
  }
}

/**
 * Fetch all models from a custom OpenAI-compatible provider.
 * Uses GET /v1/models (standard endpoint).
 */
export async function getCustomModels(
  baseUrl: string,
  apiKey?: string
): Promise<{ success: boolean; models: string[]; error?: string }> {
  if (!baseUrl) {
    return { success: false, models: [], error: 'Base URL is required' }
  }

  const cleanUrl = baseUrl.replace(/\/$/, '').replace(/\/v1$/, '')
  return fetchModelsFromEndpoint(`${cleanUrl}/v1/models`, apiKey)
}

/**
 * Fetch embedding-specific models from a custom provider.
 * Tries GET /v1/embeddings/models first (OpenRouter-specific endpoint that returns
 * only embedding models). Falls back to GET /v1/models filtered by common
 * embedding model name patterns if the dedicated endpoint is unavailable.
 */
export async function getCustomEmbeddingModels(
  baseUrl: string,
  apiKey?: string
): Promise<{ success: boolean; models: string[]; error?: string }> {
  if (!baseUrl) {
    return { success: false, models: [], error: 'Base URL is required' }
  }

  const cleanUrl = baseUrl.replace(/\/$/, '').replace(/\/v1$/, '')

  // Try the OpenRouter-specific embeddings models endpoint first
  const embeddingsEndpoint = await fetchModelsFromEndpoint(
    `${cleanUrl}/v1/embeddings/models`,
    apiKey
  )

  if (embeddingsEndpoint.success && embeddingsEndpoint.models.length > 0) {
    return embeddingsEndpoint
  }

  // Fallback: fetch all models and filter by common embedding name patterns
  const allModels = await fetchModelsFromEndpoint(`${cleanUrl}/v1/models`, apiKey)

  if (!allModels.success) {
    return allModels
  }

  const embeddingKeywords = ['embed', 'embedding', 'ada', 'e5', 'bge', 'gte', 'minilm']
  const filtered = allModels.models.filter((id) =>
    embeddingKeywords.some((kw) => id.toLowerCase().includes(kw))
  )

  // If the filter finds nothing, return all models so the user can still pick
  return {
    success: true,
    models: filtered.length > 0 ? filtered : allModels.models,
  }
}