package main

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

// Credential represents the structure of a Verifiable Credential
type Credential struct {
	Context           []string               `json:"@context"`
	Type              []string               `json:"type"`
	Issuer            string                 `json:"issuer"`
	IssuanceDate      string                 `json:"issuanceDate"`
	CredentialSubject map[string]interface{} `json:"credentialSubject"`
}

// createDID generates a new DID using walt.id's API
func createDID() (string, error) {
	req, err := http.NewRequest("POST", "http://localhost:7000/did/create", nil)
	if err != nil {
		return "", err
	}
	req.Header.Set("Authorization", "Bearer YOUR_API_KEY") // Replace with actual API key

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

	if resp.StatusCode != http.StatusOK {
		return "", fmt.Errorf("failed to create DID: status %d", resp.StatusCode)
	}

	body, err := io.ReadAll(resp.Body)
	if err != nil {
		return "", err
	}

	var result map[string]string
	if err := json.Unmarshal(body, &result); err != nil {
		return "", err
	}
	return result["did"], nil
}

func main() {
	// Create issuer DID
	issuerDID, err := createDID()
	if err != nil {
		fmt.Println("Error creating issuer DID:", err)
		return
	}
	fmt.Println("Issuer DID:", issuerDID)

	// Create subject DID
	subjectDID, err := createDID()
	if err != nil {
		fmt.Println("Error creating subject DID:", err)
		return
	}
	fmt.Println("Subject DID:", subjectDID)

	// Define the credential
	credential := Credential{
		Context:      []string{"https://www.w3.org/2018/credentials/v1"},
		Type:         []string{"VerifiableCredential", "FeedbackEligibility"},
		Issuer:       issuerDID,
		IssuanceDate: time.Now().UTC().Format(time.RFC3339),
		CredentialSubject: map[string]interface{}{
			"id":       subjectDID,
			"eligible": true,
		},
	}

	// Marshal the credential to JSON
	jsonData, err := json.Marshal(credential)
	if err != nil {
		fmt.Println("Error marshaling JSON:", err)
		return
	}

	// Create HTTP request to issue the credential
	req, err := http.NewRequest("POST", "http://localhost:7000/issue", bytes.NewBuffer(jsonData))
	if err != nil {
		fmt.Println("Error creating request:", err)
		return
	}

	// Set headers
	req.Header.Set("Content-Type", "application/json")
	req.Header.Set("Authorization", "Bearer YOUR_API_KEY") // Replace with actual API key

	// Send the request
	client := &http.Client{}
	resp, err := client.Do(req)
	if err != nil {
		fmt.Println("Error sending request:", err)
		return
	}
	defer resp.Body.Close()

	// Check the response status code
	if resp.StatusCode != http.StatusOK {
		fmt.Println("Error: received status code", resp.StatusCode)
		return
	}

	// Read and display the response
	body, err := io.ReadAll(resp.Body)
	if err != nil {
		fmt.Println("Error reading response:", err)
		return
	}

	fmt.Println("Issued Credential:", string(body))
}