package classes

import (
	"context"
	"errors"
	"strconv"

	"git.golem15.com/golem15/sm-user-plugin/models"
	"git.golem15.com/golem15/summercms/modules/backpack"
	"git.golem15.com/golem15/summercms/modules/lagoon/attach"
	"gocloud.dev/blob"
	"gorm.io/gorm"
)

// OrganisationLogoSize is the edge in pixels of the logo thumbnail
// OrganisationLogoFields answers.
const OrganisationLogoSize = 256

// organisationLogo loads the organisation's logo attachment, or nil.
func organisationLogo(ctx context.Context, app *backpack.App, org *models.Organisation) (*attach.File, error) {
	if app == nil || org == nil || org.ID == 0 {
		return nil, nil
	}
	gdb, ok := app.Lookup[*gorm.DB]()
	if !ok || gdb == nil {
		return nil, nil
	}
	var f attach.File
	err := gdb.WithContext(ctx).
		Where("attachment_type = ? AND attachment_id = ? AND field = ?", org.MorphName(), strconv.FormatUint(uint64(org.ID), 10), models.OrganisationLogoField).
		Take(&f).Error
	if errors.Is(err, gorm.ErrRecordNotFound) {
		return nil, nil
	}
	if err != nil {
		return nil, err
	}
	return &f, nil
}

// OrganisationLogoURL returns the URL of the organisation's logo at size
// pixels, the way AvatarURL serves a user's picture: the thumbnail (size by
// size, mode auto) of the logo attachment, or the attachment's file path
// when the thumbnail fails (logged). It answers false when the organisation
// has no logo or no file bucket is published. The URL may be relative; a
// caller that needs an absolute URL resolves it. Only a failing database
// lookup is an error.
func OrganisationLogoURL(ctx context.Context, app *backpack.App, org *models.Organisation, size int) (string, bool, error) {
	f, err := organisationLogo(ctx, app, org)
	if err != nil || f == nil {
		return "", false, err
	}
	bucket, ok := app.Lookup[*blob.Bucket]()
	if !ok || bucket == nil {
		return "", false, nil
	}
	url, err := f.Thumb(ctx, bucket, size, size, "auto")
	if err != nil {
		pluginLog.Error("golem15.user: organisation logo thumb", "err", err)
		return "/" + attach.BlobKey(f.DiskName), true, nil
	}
	return url, true, nil
}

// OrganisationLogoFields answers the logo keys an application adds to its
// own organisation payloads, named like the user payload's avatar keys:
// has_logo (bool), logo (the attachment's disk name, or nil) and logo_url
// (the OrganisationLogoSize thumbnail URL, or nil). An organisation without
// a logo answers false, nil and nil. Only a failing database lookup is an
// error.
func OrganisationLogoFields(ctx context.Context, app *backpack.App, org *models.Organisation) (map[string]any, error) {
	out := map[string]any{"has_logo": false, "logo": nil, "logo_url": nil}
	f, err := organisationLogo(ctx, app, org)
	if err != nil {
		return nil, err
	}
	if f == nil {
		return out, nil
	}
	out["has_logo"] = true
	out["logo"] = f.DiskName
	url, ok, err := OrganisationLogoURL(ctx, app, org, OrganisationLogoSize)
	if err != nil {
		return nil, err
	}
	if ok && url != "" {
		out["logo_url"] = url
	}
	return out, nil
}