package services

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

// The structs to map OpenRouter's response
type OpenRouterResponse struct {
	Choices []struct {
		Message struct {
			Content string `json:"content"`
		} `json:"message"`
	} `json:"choices"`
}

func GetAIResponse(input string) (string, error) {
	apiKey := os.Getenv("OPENROUTER_API_KEY")
	payload := map[string]interface{}{
		"model": "google/gemini-2.0-flash-001",
		"messages": []map[string]string{
			{"role": "system", "content": "You are a Chilean business assistant. Be brief."},
			{"role": "user", "content": input},
		},
		"tools": []map[string]interface{}{
			{
				"type": "function",
				"function": map[string]interface{}{
					"name":        "create_appointment",
					"description": "Schedules a new appointment in the database",
					"parameters": map[string]interface{}{
						"type": "object",
						"properties": map[string]interface{}{
							"customer_phone": map[string]string{"type": "string"},
							"date":           map[string]string{"type": "string", "description": "ISO format date and time"},
						},
						"required": []string{"customer_phone", "date"},
					},
				},
			},
		},
	}

	data, _ := json.Marshal(payload)
	req, _ := http.NewRequest("POST", "https://openrouter.ai/api/v1/chat/completions", bytes.NewBuffer(data))
	req.Header.Set("Authorization", "Bearer "+apiKey)
	req.Header.Set("Content-Type", "application/json")

	resp, err := http.DefaultClient.Do(req)
	if err != nil {
		return "", err
	}
	defer resp.Body.Close()

	bodyBytes, _ := io.ReadAll(resp.Body)

	// If it's not a 200, return the error body so you can see why it failed
	if resp.StatusCode != http.StatusOK {
		return "API Error: " + string(bodyBytes), nil
	}

	var result OpenRouterResponse
	if err := json.Unmarshal(bodyBytes, &result); err != nil {
		return "", err
	}

	if len(result.Choices) > 0 {
		return result.Choices[0].Message.Content, nil
	}

	return "No response from AI.", nil
}