package fastly

import (
	"fmt"
	"sort"
)

// Dictionary represents a dictionary response from the Fastly API.
type Dictionary struct {
	ServiceID string `mapstructure:"service_id"`
	Version   string `mapstructure:"version"`

	ID      string `mapstructure:"id"`
	Name    string `mapstructure:"name"`
	Address string `mapstructure:"address"`
}

// dictionariesByName is a sortable list of dictionaries.
type dictionariesByName []*Dictionary

// Len, Swap, and Less implement the sortable interface.
func (s dictionariesByName) Len() int      { return len(s) }
func (s dictionariesByName) Swap(i, j int) { s[i], s[j] = s[j], s[i] }
func (s dictionariesByName) Less(i, j int) bool {
	return s[i].Name < s[j].Name
}

// ListDictionariesInput is used as input to the ListDictionaries function.
type ListDictionariesInput struct {
	// Service is the ID of the service (required).
	Service string

	// Version is the specific configuration version (required).
	Version string
}

// ListDictionaries returns the list of dictionaries for the configuration version.
func (c *Client) ListDictionaries(i *ListDictionariesInput) ([]*Dictionary, error) {
	if i.Service == "" {
		return nil, ErrMissingService
	}

	if i.Version == "" {
		return nil, ErrMissingVersion
	}

	path := fmt.Sprintf("/service/%s/version/%s/dictionary", i.Service, i.Version)
	resp, err := c.Get(path, nil)
	if err != nil {
		return nil, err
	}

	var bs []*Dictionary
	if err := decodeJSON(&bs, resp.Body); err != nil {
		return nil, err
	}
	sort.Stable(dictionariesByName(bs))
	return bs, nil
}

// CreateDictionaryInput is used as input to the CreateDictionary function.
type CreateDictionaryInput struct {
	// Service is the ID of the service. Version is the specific configuration
	// version. Both fields are required.
	Service string
	Version string

	Name string `form:"name,omitempty"`
}

// CreateDictionary creates a new Fastly dictionary.
func (c *Client) CreateDictionary(i *CreateDictionaryInput) (*Dictionary, error) {
	if i.Service == "" {
		return nil, ErrMissingService
	}

	if i.Version == "" {
		return nil, ErrMissingVersion
	}

	path := fmt.Sprintf("/service/%s/version/%s/dictionary", i.Service, i.Version)
	resp, err := c.PostForm(path, i, nil)
	if err != nil {
		return nil, err
	}

	var b *Dictionary
	if err := decodeJSON(&b, resp.Body); err != nil {
		return nil, err
	}
	return b, nil
}

// GetDictionaryInput is used as input to the GetDictionary function.
type GetDictionaryInput struct {
	// Service is the ID of the service. Version is the specific configuration
	// version. Both fields are required.
	Service string
	Version string

	// Name is the name of the dictionary to fetch.
	Name string
}

// GetDictionary gets the dictionary configuration with the given parameters.
func (c *Client) GetDictionary(i *GetDictionaryInput) (*Dictionary, error) {
	if i.Service == "" {
		return nil, ErrMissingService
	}

	if i.Version == "" {
		return nil, ErrMissingVersion
	}

	if i.Name == "" {
		return nil, ErrMissingName
	}

	path := fmt.Sprintf("/service/%s/version/%s/dictionary/%s", i.Service, i.Version, i.Name)
	resp, err := c.Get(path, nil)
	if err != nil {
		return nil, err
	}

	var b *Dictionary
	if err := decodeJSON(&b, resp.Body); err != nil {
		return nil, err
	}
	return b, nil
}

// UpdateDictionaryInput is used as input to the UpdateDictionary function.
type UpdateDictionaryInput struct {
	// Service is the ID of the service. Version is the specific configuration
	// version. Both fields are required.
	Service string
	Version string

	// Name is the name of the dictionary to update.
	Name string

	NewName string `form:"name,omitempty"`
}

// UpdateDictionary updates a specific dictionary.
func (c *Client) UpdateDictionary(i *UpdateDictionaryInput) (*Dictionary, error) {
	if i.Service == "" {
		return nil, ErrMissingService
	}

	if i.Version == "" {
		return nil, ErrMissingVersion
	}

	if i.Name == "" {
		return nil, ErrMissingName
	}

	path := fmt.Sprintf("/service/%s/version/%s/dictionary/%s", i.Service, i.Version, i.Name)
	resp, err := c.PutForm(path, i, nil)
	if err != nil {
		return nil, err
	}

	var b *Dictionary
	if err := decodeJSON(&b, resp.Body); err != nil {
		return nil, err
	}
	return b, nil
}

// DeleteDictionaryInput is the input parameter to DeleteDictionary.
type DeleteDictionaryInput struct {
	// Service is the ID of the service. Version is the specific configuration
	// version. Both fields are required.
	Service string
	Version string

	// Name is the name of the dictionary to delete (required).
	Name string
}

// DeleteDictionary deletes the given dictionary version.
func (c *Client) DeleteDictionary(i *DeleteDictionaryInput) error {
	if i.Service == "" {
		return ErrMissingService
	}

	if i.Version == "" {
		return ErrMissingVersion
	}

	if i.Name == "" {
		return ErrMissingName
	}

	path := fmt.Sprintf("/service/%s/version/%s/dictionary/%s", i.Service, i.Version, i.Name)
	_, err := c.Delete(path, nil)
	if err != nil {
		return err
	}

	// Unlike other endpoints, the dictionary endpoint does not return a status
	// response - it just returns a 200 OK.
	return nil
}