today_ai_weather/app/services/ai_service.rb

class AiService
  MODELS = {
    dalle: "dall-e-3",
    flux: "black-forest-labs/FLUX.1-schnell"
  }.freeze

  def initialize
    @client = OpenAI::Client.new(
      access_token: Rails.application.credentials.openai.token,
      uri_base: Rails.application.credentials.openai.uri,
      log_errors: Rails.env.development?,  # 只在开发环境下启用
      request_timeout: 240
    )

    # 这里假设你已经在credentials中添加了siliconflow相关配置
    @flux_token = Rails.application.credentials.siliconflow.token
    @flux_api_url = Rails.application.credentials.siliconflow.url
  end

  def generate_prompt(city, weather_data)
    # city_desc = generate_location_desc(city)
    city_desc = city.get_description('en')

    system_message =
      "You are a professional artist creating prompts for image generation. Create realistic, artistic weather scenes featuring iconic landmarks."
    user_message = generate_image_prompt_request(city, weather_data, city_desc)
    ask_ai(system_message, user_message)
  end

  # def generate_location_desc(city)
  #   region = city.country.region&.name || ""
  #   country = city.country.name || ""
  #   state = city.state&.name || ""

  #   system_message =
  #     "You are a global geography master, you understand the culture, geography, architecture, customs and other information of all cities around the world. Describe this city based on the city I gave you. Include details about its culture, climate, landmarks, and any unique features that make this place special. Condense the keyword into a description of about 50 words"
  #   user_message =
  #     "Describe the characteristics of the city of #{city.name}, located in the #{state}, #{country}, #{region}"
  #   ask_ai(system_message, user_message)
  # end

  def generate_image(prompt, model_type = :flux)
    case model_type
    when :flux
      generate_image_flux(prompt)
    when :dalle
      generate_image_dalle(prompt)
    else
      generate_image_flux(prompt) # 默认使用FLUX
    end
  end

  def generate_image_dalle(prompt)
    response = @client.images.generate(
      parameters: {
        model: MODELS[:dalle],
        prompt: prompt,
        size: "1792x1024",
        quality: "hd",
        n: 1
      }
    )

    response.dig("data", 0, "url")
  end

  def generate_image_flux(prompt)
    uri = URI(@flux_api_url)
    http = Net::HTTP.new(uri.host, uri.port)
    http.use_ssl = true

    request = Net::HTTP::Post.new(uri)
    request["Authorization"] = "Bearer #{@flux_token}"
    request["Content-Type"] = "application/json"

    # 生成随机种子
    seed = rand(10000000000)

    request.body = {
      model: MODELS[:flux],
      prompt: prompt,
      # image_size: "1024x576",
      image_size: "1792x1024",
      seed: seed,
      prompt_enhancement: false
    }.to_json

    response = http.request(request)

    if response.is_a?(Net::HTTPSuccess)
      result = JSON.parse(response.body)
      result.dig("data", 0, "url")
    else
      Rails.logger.error("FLUX API error: #{response.code} - #{response.body}")
      # 异常时回退到DALL-E
      # generate_image_dalle(prompt)
    end
  rescue => e
    Rails.logger.error("Error generating image with FLUX: #{e.message}")
    # 异常时回退到DALL-E
    # generate_image_dalle(prompt)
  end

  def ask_ai(system_message, user_message)
    response = @client.chat(
      parameters: {
        model: "gpt-4o-mini",
        messages:
          [ {
              role: "system",
              content: system_message
            }, {
              role: "user",
              content: user_message
            } ],
        temperature: 0.7,
        max_tokens: 300
      }
    )
    response.dig("choices", 0, "message", "content")
  end

  private

  def generate_image_prompt_request(city, weather_data, city_desc)
    region = city.country.region&.name || ""
    country = city.country.name || ""
    state = city.state&.name || ""

    <<~PROMPT
      Generate a highly detailed and photorealistic image prompt capturing a specific weather moment in #{city.name}, #{state}, #{country}, #{region}.

      **Scene Inspiration:**
      #{city_desc}
      (Use this description to inform the specific elements and mood of the scene).

      **Weather Conditions to Depict:**
      - Temperature Feel: Convey the atmosphere associated with #{weather_data[:temperature]}°C.
      - Visible Weather: #{weather_data[:description]}. Show its effects on the environment (e.g., rain slicking streets, sun casting sharp shadows, fog softening distant objects).
      - Sky & Light: Sky is #{weather_data[:cloud]}% cloud covered. Render the lighting accurately for the time: #{weather_data[:time]} (e.g., warm morning light, bright midday sun, soft afternoon light, dramatic sunset colors, twilight ambiance, or night scene lighting like streetlights).

      **Mandatory Requirements for Realism and Aesthetics:**
      - **Style:** Photorealistic photograph, hyperrealistic, cinematic quality. Capture fine details, textures (e.g., wet pavement, brickwork, foliage), and accurate lighting.
      - **Composition:** Atmospheric and artistic composition (e.g., rule of thirds, leading lines), creating depth and visual interest. Consider a natural eye-level perspective or a slightly elevated viewpoint for landscape/cityscape.
      - **Landmarks/Architecture:** Feature iconic landmarks or characteristic architecture from #{city.name} as naturally integrated elements within the scene.
      - **Clarity & Brightness:** Ensure the image is sharp, clear, and well-exposed. Avoid excessive blur or motion artifacts unless intentionally used for artistic effect (like long exposure for rain).
      - **Lighting Enhancement:**
          - Even in overcast conditions (high #{weather_data[:cloud]}), maintain visual appeal with soft, diffused light, ensuring details in shadows are visible and colors remain natural yet engaging.
          - On sunny days (low #{weather_data[:cloud]}%), emphasize the brightness, warmth, contrast, and potentially lens flare for added realism.
      - **Avoid:** Do NOT produce illustrations, paintings, sketches, anime, cartoons, or overly stylized digital art. The final image must look like a real photograph.

      **Output Format:** Directly output the complete, detailed image generation prompt string only. No introductory text, labels, or explanations.
    PROMPT
  end
end