package geddit

import "encoding/json"

const (
	kindComment   = "t1"
	kindAccount   = "t2"
	kindLink      = "t3"
	kindMessage   = "t4"
	kindSubreddit = "t5"
	kindAward     = "t6"
	kindListing   = "Listing"
	kindUserList  = "UserList"
	kindMode      = "more"
)

type root struct {
	Kind string      `json:"kind,omitempty"`
	Data interface{} `json:"data,omitempty"`
}

type rootListing struct {
	Kind string   `json:"kind,omitempty"`
	Data *Listing `json:"data"`
}

// Listing holds things coming from the Reddit API
// It also contains the after/before anchors useful for subsequent requests
type Listing struct {
	Things Things `json:"children"`
	After  string `json:"after"`
	Before string `json:"before"`
}

// Things are stuff!
type Things struct {
	Comments   []Comment   `json:"comments,omitempty"`
	Links      []Link      `json:"links,omitempty"`
	Subreddits []Subreddit `json:"subreddits,omitempty"`
	// todo: add the other kinds of things
}

type commentRoot struct {
	Kind string   `json:"kind,omitempty"`
	Data *Comment `json:"data,omitempty"`
}

type linkRoot struct {
	Kind string `json:"kind,omitempty"`
	Data *Link  `json:"data,omitempty"`
}

type subredditRoot struct {
	Kind string     `json:"kind,omitempty"`
	Data *Subreddit `json:"data,omitempty"`
}

// UnmarshalJSON implements the json.Unmarshaler interface.
func (l *Things) UnmarshalJSON(b []byte) error {
	var children []map[string]interface{}
	if err := json.Unmarshal(b, &children); err != nil {
		return err
	}

	for _, child := range children {
		byteValue, _ := json.Marshal(child)
		switch child["kind"] {
		case kindComment:
			root := new(commentRoot)
			if err := json.Unmarshal(byteValue, root); err == nil && root.Data != nil {
				l.Comments = append(l.Comments, *root.Data)
			}
		case kindAccount:
		case kindLink:
			root := new(linkRoot)
			if err := json.Unmarshal(byteValue, root); err == nil && root.Data != nil {
				l.Links = append(l.Links, *root.Data)
			}
		case kindMessage:
		case kindSubreddit:
			root := new(subredditRoot)
			if err := json.Unmarshal(byteValue, root); err == nil && root.Data != nil {
				l.Subreddits = append(l.Subreddits, *root.Data)
			}
		case kindAward:
		}
	}

	return nil
}

// Comment is a comment posted by a user
type Comment struct {
	ID        string `json:"id,omitempty"`
	FullID    string `json:"name,omitempty"`
	ParentID  string `json:"parent_id,omitempty"`
	Permalink string `json:"permalink,omitempty"`

	Body            string `json:"body,omitempty"`
	Author          string `json:"author,omitempty"`
	AuthorID        string `json:"author_fullname,omitempty"`
	AuthorFlairText string `json:"author_flair_text,omitempty"`
	AuthorFlairID   string `json:"author_flair_template_id,omitempty"`

	Subreddit             string `json:"subreddit,omitempty"`
	SubredditNamePrefixed string `json:"subreddit_name_prefixed,omitempty"`
	SubredditID           string `json:"subreddit_id,omitempty"`

	Score            int `json:"score"`
	Controversiality int `json:"controversiality"`

	Created *Timestamp `json:"created_utc,omitempty"`
	Edited  *Timestamp `json:"edited,omitempty"`

	LinkID string `json:"link_id,omitempty"`

	// These don't appear when submitting a comment
	LinkTitle       string `json:"link_title,omitempty"`
	LinkPermalink   string `json:"link_permalink,omitempty"`
	LinkAuthor      string `json:"link_author,omitempty"`
	LinkNumComments int    `json:"num_comments"`

	IsSubmitter bool `json:"is_submitter"`
	ScoreHidden bool `json:"score_hidden"`
	Saved       bool `json:"saved"`
	Stickied    bool `json:"stickied"`
	Locked      bool `json:"locked"`
	CanGild     bool `json:"can_gild"`
	NSFW        bool `json:"over_18"`

	// If a comment has no replies, its "replies" value is "",
	// which the unmarshaler doesn't like
	// So we capture this varying field in RepliesRaw, and then
	// fill it in Replies
	RepliesRaw json.RawMessage `json:"replies,omitempty"`
	Replies    []commentRoot   `json:"-"`
}

// Link is a submitted post on Reddit
type Link struct {
	ID      string     `json:"id,omitempty"`
	FullID  string     `json:"name,omitempty"`
	Created *Timestamp `json:"created_utc,omitempty"`
	Edited  *Timestamp `json:"edited,omitempty"`

	Permalink string `json:"permalink,omitempty"`
	URL       string `json:"url,omitempty"`

	Title string `json:"title,omitempty"`
	Body  string `json:"selftext,omitempty"`

	Score            int `json:"score"`
	NumberOfComments int `json:"num_comments"`

	SubredditID           string `json:"subreddit_id,omitempty"`
	SubredditName         string `json:"subreddit,omitempty"`
	SubredditNamePrefixed string `json:"subreddit_name_prefixed,omitempty"`

	AuthorID   string `json:"author_fullname,omitempty"`
	AuthorName string `json:"author,omitempty"`

	Spoiler    bool `json:"spoiler"`
	Locked     bool `json:"locked"`
	NSFW       bool `json:"over_18"`
	IsSelfPost bool `json:"is_self"`
	Saved      bool `json:"saved"`
	Stickied   bool `json:"stickied"`
}

// Subreddit holds information about a subreddit
type Subreddit struct {
	ID      string     `json:"id,omitempty"`
	FullID  string     `json:"name,omitempty"`
	Created *Timestamp `json:"created_utc,omitempty"`

	URL                  string `json:"url,omitempty"`
	Name                 string `json:"display_name,omitempty"`
	NamePrefixed         string `json:"display_name_prefixed,omitempty"`
	Title                string `json:"title,omitempty"`
	PublicDescription    string `json:"public_description,omitempty"`
	Type                 string `json:"subreddit_type,omitempty"`
	SuggestedCommentSort string `json:"suggested_comment_sort,omitempty"`

	Subscribers     int  `json:"subscribers"`
	ActiveUserCount *int `json:"active_user_count,omitempty"`
	NSFW            bool `json:"over18"`
	UserIsMod       bool `json:"user_is_moderator"`
}

func (rl *rootListing) getAfter() string {
	if rl == nil || rl.Data == nil {
		return ""
	}
	return rl.Data.After
}

func (rl *rootListing) getBefore() string {
	if rl == nil || rl.Data == nil {
		return ""
	}
	return rl.Data.Before
}

func (rl *rootListing) getComments() *Comments {
	if rl == nil || rl.Data == nil {
		return nil
	}
	return &Comments{
		Comments: rl.Data.Things.Comments,
		After:    rl.Data.After,
		Before:   rl.Data.Before,
	}
}

func (rl *rootListing) getLinks() *Links {
	if rl == nil || rl.Data == nil {
		return nil
	}
	return &Links{
		Links:  rl.Data.Things.Links,
		After:  rl.Data.After,
		Before: rl.Data.Before,
	}
}

func (rl *rootListing) getSubreddits() *Subreddits {
	if rl == nil || rl.Data == nil {
		return nil
	}
	return &Subreddits{
		Subreddits: rl.Data.Things.Subreddits,
		After:      rl.Data.After,
		Before:     rl.Data.Before,
	}
}

// Comments is a list of comments
type Comments struct {
	Comments []Comment `json:"comments,omitempty"`
	After    string    `json:"after"`
	Before   string    `json:"before"`
}

// Subreddits is a list of subreddits
type Subreddits struct {
	Subreddits []Subreddit `json:"subreddits,omitempty"`
	After      string      `json:"after"`
	Before     string      `json:"before"`
}

// Links is a list of links
type Links struct {
	Links  []Link `json:"submissions,omitempty"`
	After  string `json:"after"`
	Before string `json:"before"`
}

// CommentsLinks is a list of comments and links
type CommentsLinks struct {
	Comments []Comment `json:"comments,omitempty"`
	Links    []Link    `json:"links,omitempty"`
	After    string    `json:"after"`
	Before   string    `json:"before"`
}

// CommentsLinksSubreddits is a list of comments, links, and subreddits
type CommentsLinksSubreddits struct {
	Comments   []Comment   `json:"comments,omitempty"`
	Links      []Link      `json:"links,omitempty"`
	Subreddits []Subreddit `json:"subreddits,omitempty"`
}