Sentiment Analyzer

package main

import (
	"bytes"
	"encoding/json"
	"fmt"
	"io"
	"net/http"
)

type Message struct {
	Role    string `json:"role"`
	Content string `json:"content"`
}

type SentimentResult struct {
	Sentiment  string  `json:"sentiment"`
	Confidence float64 `json:"confidence"`
}

func analyze(system []Message, input string) SentimentResult {
	msgs := append(system, Message{Role: "user", Content: input})
	body, _ := json.Marshal(map[string]any{
		"model":    "llama3.2",
		"messages": msgs,
		"stream":   false,
		"format":   "json",
	})

	resp, err := http.Post("http://localhost:11434/api/chat", "application/json", bytes.NewReader(body))
	if err != nil {
		fmt.Println("Error:", err)
		return SentimentResult{}
	}
	defer resp.Body.Close()

	data, _ := io.ReadAll(resp.Body)
	var apiResp struct {
		Message struct {
			Content string `json:"content"`
		} `json:"message"`
	}
	json.Unmarshal(data, &apiResp)

	var result SentimentResult
	json.Unmarshal([]byte(apiResp.Message.Content), &result)
	return result
}

func main() {
	messages := []Message{
		{Role: "system", Content: `Analyze the sentiment of the user's message.
Return JSON: {"sentiment": "positive|negative|neutral", "confidence": 0.0-1.0}
Return only the JSON. No explanation.`},
	}

	inputs := []string{
		"I love this product, it works perfectly!",
		"The delivery was late and the box was damaged.",
		"I ordered a blue shirt in size medium.",
	}

	for _, input := range inputs {
		result := analyze(messages, input)
		fmt.Printf("%-50s → %s (%.0f%%)\n", input, result.Sentiment, result.Confidence*100)
	}
	// I love this product, it works perfectly!            → positive (92%)
	// The delivery was late and the box was damaged.      → negative (88%)
	// I ordered a blue shirt in size medium.              → neutral (95%)
}