package discourse

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

type topic struct {
	Body            string `json:"raw"`
	TargetUsernames string `json:"target_usernames"`
	Title           string `json:"title"`
	ArchType        string `json:"archetype"`
}

type errorResponse struct {
	Action string   `json:"action"`
	Errors []string `json:"errors"`
}

type newPMResponse struct {
	ID int `json:"id"`
}

const pmArchtype = "private_message"

// SendPM - Send a PM on the discouse forum
func SendPM(apiConfig APIConfig, recipients []string, title, body string) (int, error) {
	newPm := topic{
		ArchType:        pmArchtype,
		TargetUsernames: strings.Join(recipients, ","),
		Title:           title,
		Body:            body,
	}

	payload, _ := json.Marshal(newPm)
	fmt.Println(string(payload))
	url := fmt.Sprintf("%s/posts.json?api_key=%s&api_username=%s",
		apiConfig.Endpoint, apiConfig.APIKey, apiConfig.APIUsername)

	response, err := http.Post(url, "application/json", bytes.NewBuffer(payload))
	if err != nil {
		return 0, err
	}

	if response.StatusCode != 200 {
		var errorResult errorResponse
		json.NewDecoder(response.Body).Decode(&errorResult)

		return 0, fmt.Errorf("Failed to send PM. %s", strings.Join(errorResult.Errors, "; "))
	}

	var result newPMResponse

	json.NewDecoder(response.Body).Decode(&result)

	return result.ID, nil
}