import (
    "github.com/LingByte/ling-base/relay"
    "github.com/LingByte/ling-base/relay/channel/openai"
)

client := relay.New(
    relay.WithProvider(openai.NewProvider("sk-xxx")),
)

resp, err := client.Chat(ctx, &relay.ChatRequest{
    Model: "gpt-4o",
    Messages: []relay.Message{
        {Role: "system", Content: "You are a helpful assistant."},
        {Role: "user", Content: "Hello!"},
    },
    Temperature: ptr(0.7),
    MaxTokens:   ptr(1000),
})
if err != nil {
    log.Fatal(err)
}
fmt.Println(resp.Choices[0].Message.Content)
fmt.Printf("Usage: prompt=%d completion=%d\n",
    resp.Usage.PromptTokens, resp.Usage.CompletionTokens)

result, err := client.ChatStream(ctx, &relay.ChatRequest{
    Model: "gpt-4o",
    Messages: []relay.Message{
        {Role: "user", Content: "Write a poem about Go."},
    },
})
if err != nil {
    log.Fatal(err)
}

for chunk := range result.Ch {
    if chunk.Err != nil {
        log.Fatal(chunk.Err)
    }
    if chunk.Delta != "" {
        fmt.Print(chunk.Delta)
    }
    if chunk.Done {
        break
    }
}
fmt.Printf("final usage: %+v\n", result.Usage)

messages := []relay.Message{
    {Role: "system", Content: "You are a helpful assistant."},
}

messages = append(messages, relay.Message{Role: "user", Content: "Hi!"})
resp, _ := client.Chat(ctx, &relay.ChatRequest{Model: "gpt-4o", Messages: messages})
messages = append(messages, relay.Message{
    Role:    "assistant",
    Content: resp.Choices[0].Message.Content,
})

messages = append(messages, relay.Message{Role: "user", Content: "Tell me more."})
resp, _ = client.Chat(ctx, &relay.ChatRequest{Model: "gpt-4o", Messages: messages})

import "github.com/LingByte/ling-base/relay/relaykit/dto"

resp, err := client.Chat(ctx, &relay.ChatRequest{
    Model: "gpt-4o",
    Messages: []relay.Message{
        {Role: "user", Content: "What's the weather in Beijing?"},
    },
    Tools: []relay.Tool{
        {
            Type: "function",
            Function: dto.FunctionRequest{
                Name:        "get_weather",
                Description: "Get weather for a city",
                Parameters: map[string]any{
                    "type": "object",
                    "properties": map[string]any{
                        "city": map[string]any{"type": "string"},
                    },
                    "required": []string{"city"},
                },
            },
        },
    },
})
// 解析 resp.Choices[0].Message.ToolCalls，执行工具后把 tool_result 消息追加进 Messages 再 Chat

resp, err := client.Chat(ctx, req)
if err != nil {
    var relayErr *relay.RelayError
    if errors.As(err, &relayErr) {
        fmt.Printf("provider=%s model=%s status=%d code=%s\n",
            relayErr.Provider, relayErr.Model,
            relayErr.StatusCode, relayErr.Code)
        if relayErr.IsRetryable() {
            // 可重试错误（429 / 5xx）
        }
    }
}