package main

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

func required(name string) string {
	value := os.Getenv(name)
	if value == "" {
		panic("Missing required environment variable " + name)
	}
	return value
}

func env(name, fallback string) string {
	value := os.Getenv(name)
	if value == "" {
		return fallback
	}
	return value
}

func main() {
	identityURL := env("DECISIOQ_IDENTITY_URL", "https://identity.vinquery.com/connect/token")
	catalogURL := strings.TrimRight(env("DECISIOQ_DKS_URL", "https://dks.vinquery.com"), "/")
	decisionServiceURL := strings.TrimRight(env("DECISIOQ_DDE_URL", "https://dde.vinquery.com"), "/")
	correlationID := fmt.Sprintf("auto-auct-044-go-%d", time.Now().Unix())

	tokenPayload, _ := json.Marshal(map[string]string{
		"clientId": required("DECISIOQ_CLIENT_ID"),
    "clientSecret": required("DECISIOQ_CLIENT_SECRET"),
		"audience":   env("DECISIOQ_AUDIENCE", "vinquery:api:decisioq"),
	})

	tokenBody := do("POST", identityURL, tokenPayload, "", correlationID)
	var tokenResponse struct {
		JwtToken string `json:"jwtToken"`
	}
	if err := json.Unmarshal(tokenBody, &tokenResponse); err != nil {
		panic(err)
	}

	do("GET", catalogURL+"/decisioncatalog/decisions/AUTO-AUCT-044", nil, tokenResponse.JwtToken, correlationID)
	payload, err := os.ReadFile("auto-auct-044-execute.json")
	if err != nil {
		panic(err)
	}
	result := do("POST", decisionServiceURL+"/api/v1/decide", payload, tokenResponse.JwtToken, correlationID)
	fmt.Println(string(result))
}

func do(method, url string, body []byte, token, correlationID string) []byte {
	var reader io.Reader
	if body != nil {
		reader = bytes.NewReader(body)
	}
	req, err := http.NewRequest(method, url, reader)
	if err != nil {
		panic(err)
	}
	req.Header.Set("Content-Type", "application/json")
	req.Header.Set("X-Correlation-Id", correlationID)
	if token != "" {
		req.Header.Set("Authorization", "Bearer "+token)
	}
	resp, err := http.DefaultClient.Do(req)
	if err != nil {
		panic(err)
	}
	defer resp.Body.Close()
	responseBody, _ := io.ReadAll(resp.Body)
	if resp.StatusCode >= 400 {
		panic(fmt.Sprintf("HTTP %d: %s", resp.StatusCode, string(responseBody)))
	}
	return responseBody
}