package discourse

import (
	"encoding/json"
	"fmt"
	"strings"
)

type pmPayload 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 := pmPayload{
		ArchType:        pmArchtype,
		TargetUsernames: strings.Join(recipients, ","),
		Title:           title,
		Body:            body,
	}

	payload, _ := json.Marshal(newPm)

	url := fmt.Sprintf("%s/posts.json", apiConfig.Endpoint)

	req, _ := newPostRequest(apiConfig, url, payload)
	client := getClient(rl)

	response, err := client.Do(req)

	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
}