package caldav

import (
	"fmt"
	"net/http"

	"github.com/emersion/go-webdav"
	"github.com/emersion/go-webdav/internal"
)

// Client provides access to a remote CardDAV server.
type Client struct {
	*webdav.Client

	ic *internal.Client
}

func NewClient(c *http.Client, endpoint string) (*Client, error) {
	wc, err := webdav.NewClient(c, endpoint)
	if err != nil {
		return nil, err
	}
	ic, err := internal.NewClient(c, endpoint)
	if err != nil {
		return nil, err
	}
	return &Client{wc, ic}, nil
}

func (c *Client) SetBasicAuth(username, password string) {
	c.Client.SetBasicAuth(username, password)
	c.ic.SetBasicAuth(username, password)
}

func (c *Client) FindCalendarHomeSet(principal string) (string, error) {
	propfind := internal.NewPropNamePropfind(calendarHomeSetName)
	resp, err := c.ic.PropfindFlat(principal, propfind)
	if err != nil {
		return "", err
	}

	var prop calendarHomeSet
	if err := resp.DecodeProp(&prop); err != nil {
		return "", err
	}

	return prop.Href.Path, nil
}

func (c *Client) FindCalendars(calendarHomeSet string) ([]Calendar, error) {
	propfind := internal.NewPropNamePropfind(
		internal.ResourceTypeName,
		internal.DisplayNameName,
		calendarDescriptionName,
		maxResourceSizeName,
	)
	ms, err := c.ic.Propfind(calendarHomeSet, internal.DepthOne, propfind)
	if err != nil {
		return nil, err
	}

	l := make([]Calendar, 0, len(ms.Responses))
	for _, resp := range ms.Responses {
		path, err := resp.Path()
		if err != nil {
			return nil, err
		}

		var resType internal.ResourceType
		if err := resp.DecodeProp(&resType); err != nil {
			return nil, err
		}
		if !resType.Is(calendarName) {
			continue
		}

		var desc calendarDescription
		if err := resp.DecodeProp(&desc); err != nil && !internal.IsNotFound(err) {
			return nil, err
		}

		var dispName internal.DisplayName
		if err := resp.DecodeProp(&dispName); err != nil && !internal.IsNotFound(err) {
			return nil, err
		}

		var maxResSize maxResourceSize
		if err := resp.DecodeProp(&maxResSize); err != nil && !internal.IsNotFound(err) {
			return nil, err
		}
		if maxResSize.Size < 0 {
			return nil, fmt.Errorf("carddav: max-resource-size must be a positive integer")
		}

		l = append(l, Calendar{
			Path:            path,
			Name:            dispName.Name,
			Description:     desc.Description,
			MaxResourceSize: maxResSize.Size,
		})
	}

	return l, nil
}