//! OpenAI API 数据模型
//!
//! 用于 OpenAI Chat Completions API 的请求/响应格式转换

use serde::{Deserialize, Serialize};
use serde_json::Value;

/// OpenAI 请求
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct OpenAIRequest {
    pub model: String,
    pub messages: Vec<OpenAIMessage>,
    #[serde(skip_serializing_if = "Option::is_none")]
    pub max_tokens: Option<u32>,
    #[serde(skip_serializing_if = "Option::is_none")]
    pub temperature: Option<f32>,
    #[serde(skip_serializing_if = "Option::is_none")]
    pub stream: Option<bool>,
    #[serde(skip_serializing_if = "Option::is_none")]
    pub tools: Option<Vec<OpenAITool>>,
    #[serde(skip_serializing_if = "Option::is_none")]
    pub tool_choice: Option<Value>,
}

/// OpenAI 消息
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct OpenAIMessage {
    pub role: String,
    #[serde(skip_serializing_if = "Option::is_none")]
    pub content: Option<Value>, // String 或 Vec<ContentPart>
    #[serde(skip_serializing_if = "Option::is_none")]
    pub tool_calls: Option<Vec<OpenAIToolCall>>,
    #[serde(skip_serializing_if = "Option::is_none")]
    pub tool_call_id: Option<String>,
}

/// OpenAI 内容部分
#[derive(Debug, Clone, Serialize, Deserialize)]
#[serde(tag = "type")]
pub enum OpenAIContentPart {
    #[serde(rename = "text")]
    Text { text: String },
    #[serde(rename = "image_url")]
    ImageUrl { image_url: ImageUrl },
}

/// 图片 URL
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct ImageUrl {
    pub url: String,
}

/// OpenAI 工具调用
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct OpenAIToolCall {
    pub id: String,
    #[serde(rename = "type")]
    pub call_type: String,
    pub function: OpenAIFunction,
}

/// OpenAI 函数
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct OpenAIFunction {
    pub name: String,
    pub arguments: String, // JSON 字符串
}

/// OpenAI 工具定义
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct OpenAITool {
    #[serde(rename = "type")]
    pub tool_type: String,
    pub function: OpenAIFunctionDef,
}

/// OpenAI 函数定义
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct OpenAIFunctionDef {
    pub name: String,
    #[serde(skip_serializing_if = "Option::is_none")]
    pub description: Option<String>,
    pub parameters: Value,
}

/// OpenAI 响应
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct OpenAIResponse {
    pub id: String,
    pub object: String,
    pub created: u64,
    pub model: String,
    pub choices: Vec<OpenAIChoice>,
    #[serde(skip_serializing_if = "Option::is_none")]
    pub usage: Option<OpenAIUsage>,
}

/// OpenAI 选择
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct OpenAIChoice {
    pub index: u32,
    pub message: OpenAIMessage,
    #[serde(skip_serializing_if = "Option::is_none")]
    pub finish_reason: Option<String>,
}

/// OpenAI 使用量
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct OpenAIUsage {
    pub prompt_tokens: u32,
    pub completion_tokens: u32,
    pub total_tokens: u32,
}