package builder

import (
	"context"
	"git.dragse.it/anthrove/e621-sdk-go/pkg/e621/endpoints"
	"git.dragse.it/anthrove/e621-sdk-go/pkg/e621/model"
	"strconv"
)

// FavoritesBuilder represents a builder for constructing queries to retrieve user's favorite posts.
type FavoritesBuilder interface {
	// SetUserID sets the user ID for the query.
	SetUserID(userID model.UserID) FavoritesBuilder
	// SetLimit sets the maximum number of favorite posts to retrieve.
	SetLimit(limitFavorites int) FavoritesBuilder
	// Page sets the page number for paginated results.
	Page(pageNumber int) FavoritesBuilder
	// Execute sends the constructed query and returns a slice of favorite posts and an error if any.
	Execute() ([]model.Post, error)
}

// NewGetFavoritesBuilder creates a new instance of FavoritesBuilder with the provided RequestContext.
//
// Parameters:
//   - requestContext: The context for the API request, including the host, user agent, username, and API key.
//
// Returns:
//   - FavoritesBuilder: An instance of the FavoritesBuilder interface.
func NewGetFavoritesBuilder(requestContext model.RequestContext) FavoritesBuilder {
	return &getFavorites{
		requestContext: requestContext,
		query:          make(map[string]string),
	}
}

// getFavorites is an implementation of the FavoritesBuilder interface.
type getFavorites struct {
	query          map[string]string
	requestContext model.RequestContext
}

// SetUserID sets the user ID for the query.
//
// Parameters:
//   - userID: The ID of the user whose favorite posts are to be retrieved.
//
// Returns:
//   - FavoritesBuilder: The instance of the FavoritesBuilder for method chaining.
func (g *getFavorites) SetUserID(userID model.UserID) FavoritesBuilder {
	g.query["user_id"] = strconv.Itoa(int(userID))
	return g
}

// SetLimit sets the maximum number of favorite posts to retrieve.
//
// Parameters:
//   - limitFavorites: The maximum number of favorite posts to retrieve.
//
// Returns:
//   - FavoritesBuilder: The instance of the FavoritesBuilder for method chaining.
func (g *getFavorites) SetLimit(limitFavorites int) FavoritesBuilder {
	g.query["limit"] = strconv.Itoa(limitFavorites)
	return g
}

// Page sets the page number for paginated results.
//
// Parameters:
//   - pageNumber: The page number for paginated results.
//
// Returns:
//   - FavoritesBuilder: The instance of the FavoritesBuilder for method chaining.
func (g *getFavorites) Page(pageNumber int) FavoritesBuilder {
	g.query["page"] = strconv.Itoa(pageNumber)
	return g
}

// Execute sends the constructed query and returns a slice of favorite posts and an error if any.
//
// Returns:
//   - []model.Post: A slice of favorite posts.
//   - error: An error, if any, encountered during the API request or response handling.
func (g *getFavorites) Execute() ([]model.Post, error) {
	if g.requestContext.RateLimiter != nil {
		err := g.requestContext.RateLimiter.Wait(context.Background())
		if err != nil {
			return nil, err
		}
	}
	favorites, err := endpoints.GetFavorites(g.requestContext, g.query)
	if err != nil {
		return nil, err
	}
	return favorites, nil
}