package route

import (
	"context"
	"net/http"
	"strconv"

	"github.com/microcosm-cc/bluemonday"

	"forge.cadoles.com/wpetit/fake-smtp/internal/command"
	"forge.cadoles.com/wpetit/fake-smtp/internal/model"
	"forge.cadoles.com/wpetit/fake-smtp/internal/query"
	"forge.cadoles.com/wpetit/fake-smtp/internal/storm"
	"github.com/go-chi/chi"
	"github.com/pkg/errors"
	"gitlab.com/wpetit/goweb/cqrs"
	"gitlab.com/wpetit/goweb/middleware/container"
	"gitlab.com/wpetit/goweb/service/template"
)

func serveEmailPage(w http.ResponseWriter, r *http.Request) {
	emailID, err := getEmailID(r)
	if err != nil {
		http.Error(w, http.StatusText(http.StatusBadRequest), http.StatusBadRequest)

		return
	}

	ctx := r.Context()

	email, err := openEmail(ctx, emailID)
	if err != nil {
		if errors.Is(err, storm.ErrNotFound) {
			http.Error(w, http.StatusText(http.StatusNotFound), http.StatusNotFound)

			return
		}

		panic(errors.Wrap(err, "could not open email"))
	}

	ctn := container.Must(ctx)
	tmpl := template.Must(ctn)

	data := extendTemplateData(w, r, template.Data{
		"Email": email,
	})

	if err := tmpl.RenderPage(w, "email.html.tmpl", data); err != nil {
		panic(errors.Wrapf(err, "could not render '%s' page", r.URL.Path))
	}
}

func serveEmailHTMLContent(w http.ResponseWriter, r *http.Request) {
	emailID, err := getEmailID(r)
	if err != nil {
		http.Error(w, http.StatusText(http.StatusBadRequest), http.StatusBadRequest)

		return
	}

	ctx := r.Context()

	email, err := openEmail(ctx, emailID)
	if err != nil {
		if errors.Is(err, storm.ErrNotFound) {
			http.Error(w, http.StatusText(http.StatusNotFound), http.StatusNotFound)

			return
		}

		panic(errors.Wrap(err, "could not open email"))
	}

	html := email.HTML

	if html == "" {
		http.Error(w, http.StatusText(http.StatusNoContent), http.StatusNoContent)

		return
	}

	policy := bluemonday.UGCPolicy()
	sanitizedHTML := policy.Sanitize(email.HTML)

	w.Header().Set("Content-Type", "text/html")
	w.Write([]byte(sanitizedHTML))
}

func serveEmailAttachment(w http.ResponseWriter, r *http.Request) {
	emailID, err := getEmailID(r)
	if err != nil {
		http.Error(w, http.StatusText(http.StatusBadRequest), http.StatusBadRequest)

		return
	}

	ctx := r.Context()

	email, err := openEmail(ctx, emailID)
	if err != nil {
		if errors.Is(err, storm.ErrNotFound) {
			http.Error(w, http.StatusText(http.StatusNotFound), http.StatusNotFound)

			return
		}

		panic(errors.Wrap(err, "could not open email"))
	}

	attachmentIndex, err := getAttachmentIndex(r)
	if err != nil {
		if errors.Is(err, storm.ErrNotFound) {
			http.Error(w, http.StatusText(http.StatusNotFound), http.StatusNotFound)

			return
		}

		panic(errors.Wrap(err, "could not open attachment"))
	}

	if attachmentIndex < 0 || attachmentIndex >= len(email.Attachments) {
		http.Error(w, http.StatusText(http.StatusNotFound), http.StatusNotFound)

		return
	}

	attachment := email.Attachments[attachmentIndex]

	w.Header().Set("Content-Type", attachment.ContentType)

	if _, err := w.Write(attachment.Data); err != nil {
		panic(errors.Wrap(err, "could not send attachment"))
	}
}

func handleEmailDelete(w http.ResponseWriter, r *http.Request) {
	emailID, err := getEmailID(r)
	if err != nil {
		http.Error(w, http.StatusText(http.StatusBadRequest), http.StatusBadRequest)

		return
	}

	ctx := r.Context()
	ctn := container.Must(ctx)
	bus := cqrs.Must(ctn)

	deleteEmail := &command.DeleteEmailRequest{
		EmailID: emailID,
	}

	if _, err := bus.Exec(ctx, deleteEmail); err != nil {
		panic(errors.Wrap(err, "could not delete email"))
	}

	http.Error(w, http.StatusText(http.StatusNoContent), http.StatusNoContent)
}

func getEmailID(r *http.Request) (int, error) {
	rawEmailID := chi.URLParam(r, "id")

	emailID, err := strconv.ParseInt(rawEmailID, 10, 32)
	if err != nil {
		return 0, err
	}

	return int(emailID), nil
}

func openEmail(ctx context.Context, emailID int) (*model.Email, error) {
	ctn := container.Must(ctx)
	bus := cqrs.Must(ctn)
	req := &query.OpenEmailRequest{
		EmailID: int(emailID),
	}

	result, err := bus.Query(ctx, req)
	if err != nil {
		return nil, err
	}

	openEmailData, ok := result.Data().(*query.OpenEmailData)
	if !ok {
		return nil, errors.New("unexpected result data")
	}

	return openEmailData.Email, nil
}

func getAttachmentIndex(r *http.Request) (int, error) {
	rawAttachmendIndex := chi.URLParam(r, "attachmendIndex")

	attachmendIndex, err := strconv.ParseInt(rawAttachmendIndex, 10, 32)
	if err != nil {
		return 0, err
	}

	return int(attachmendIndex), nil
}