package pdf

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

	"github.com/labstack/gommon/log"
)

type PdfService struct {
	invoicePath string
	projectId   string
	url         string
	apiKey      string
}

func NewPdfService() *PdfService {
	return &PdfService{
		invoicePath: "index.html",
		projectId:   os.Getenv("HTMLDOCS_PROJECT_ID"),
		url:         os.Getenv("HTMLDOCS_URL"),
		apiKey:      os.Getenv("HTMLDOCS_KEY"),
	}
}

func (ps PdfService) BuildInvoice() error {
	data := struct {
		Context   map[string]any `json:"context"`
		Path      string         `json:"path"`
		ProjectId string         `json:"projectId"`
	}{
		Context:   map[string]any{},
		Path:      ps.invoicePath,
		ProjectId: ps.projectId,
	}

	payload, err := json.Marshal(data)
	if err != nil {
		log.Warnf("Error marshalling JSON:", err)
		return err
	}

	// build request to third-party API
	req, err := http.NewRequest("POST", ps.url, bytes.NewBuffer(payload))
	if err != nil {
		log.Warnf("Error creating request:", err)
		return err
	}

	req.Header.Set("Authorization", "Bearer "+ps.apiKey)
	req.Header.Set("Content-Type", "application/json")

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

	res := new(struct {
		Url   string `json:"url"`
		Error string `json:"error"`
	})
	body, err := io.ReadAll(resp.Body)
	if err != nil {
		return err
	}

	err = json.Unmarshal(body, res)
	if err != nil {
		log.Warnf("error decoding response: %s", err)
		return err
	}

	if res.Error != "" {
		log.Warnf("error building pdf file %s", err)
		return errors.New(res.Error)
	}

	resp, err = http.Get(res.Url)
	if err != nil {
		log.Warnf("Error retrieving file")
		return err
	}
	defer resp.Body.Close()

	file, err := os.Create("tmp.pdf")
	if err != nil {
		log.Fatal(err)
	}
	defer file.Close()

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

	_, err = file.Write(body)
	if err != nil {
		log.Error("Error copying file content")
		return err
	}
	return nil
}