package writeas

import (
	"fmt"
	"net/http"
)

type (
	// Collection represents a collection of posts. Blogs are a type of collection
	// on Write.as.
	Collection struct {
		Alias       string `json:"alias"`
		Title       string `json:"title"`
		Description string `json:"description"`
		StyleSheet  string `json:"style_sheet"`
		Private     bool   `json:"private"`
		Views       int64  `json:"views"`
		Domain      string `json:"domain,omitempty"`
		Email       string `json:"email,omitempty"`

		TotalPosts int `json:"total_posts"`

		Posts *[]Post `json:"posts,omitempty"`
	}

	// CollectionParams holds values for creating a collection.
	CollectionParams struct {
		Alias string `json:"alias"`
		Title string `json:"title"`
	}
)

// CreateCollection creates a new collection, returning a user-friendly error
// if one comes up. Requires a Write.as subscription. See
// https://developer.write.as/docs/api/#create-a-collection
func (c *Client) CreateCollection(sp *CollectionParams) (*Collection, error) {
	p := &Collection{}
	env, err := c.post("/collections", sp, p)
	if err != nil {
		return nil, err
	}

	var ok bool
	if p, ok = env.Data.(*Collection); !ok {
		return nil, fmt.Errorf("Wrong data returned from API.")
	}

	status := env.Code
	if status == http.StatusCreated {
		return p, nil
	} else if status == http.StatusBadRequest {
		return nil, fmt.Errorf("Bad request: %s", env.ErrorMessage)
	} else if status == http.StatusForbidden {
		return nil, fmt.Errorf("Casual or Pro user required.")
	} else if status == http.StatusConflict {
		return nil, fmt.Errorf("Collection name is already taken.")
	} else if status == http.StatusPreconditionFailed {
		return nil, fmt.Errorf("Reached max collection quota.")
	}
	return nil, fmt.Errorf("Problem getting post: %d. %v\n", status, err)
}

// GetCollection retrieves a collection, returning the Collection and any error
// (in user-friendly form) that occurs. See
// https://developer.write.as/docs/api/#retrieve-a-collection
func (c *Client) GetCollection(alias string) (*Collection, error) {
	coll := &Collection{}
	env, err := c.get(fmt.Sprintf("/collections/%s", alias), coll)
	if err != nil {
		return nil, err
	}

	var ok bool
	if coll, ok = env.Data.(*Collection); !ok {
		return nil, fmt.Errorf("Wrong data returned from API.")
	}
	status := env.Code

	if status == http.StatusOK {
		return coll, nil
	} else if status == http.StatusNotFound {
		return nil, fmt.Errorf("Collection not found.")
	} else {
		return nil, fmt.Errorf("Problem getting collection: %d. %v\n", status, err)
	}
}

// GetCollectionPosts retrieves a collection's posts, returning the Posts
// and any error (in user-friendly form) that occurs. See
// https://developer.write.as/docs/api/#retrieve-collection-posts
func (c *Client) GetCollectionPosts(alias string) (*[]Post, error) {
	coll := &Collection{}
	env, err := c.get(fmt.Sprintf("/collections/%s/posts", alias), coll)
	if err != nil {
		return nil, err
	}

	var ok bool
	if coll, ok = env.Data.(*Collection); !ok {
		return nil, fmt.Errorf("Wrong data returned from API.")
	}
	status := env.Code

	if status == http.StatusOK {
		return coll.Posts, nil
	} else if status == http.StatusNotFound {
		return nil, fmt.Errorf("Collection not found.")
	} else {
		return nil, fmt.Errorf("Problem getting collection: %d. %v\n", status, err)
	}
}