package music

import (
	"encoding/json"
	"net/http"

	"github.com/jmoiron/sqlx"
)

type Artist struct {
    ID      string `json:"id"`
    Name    string `json:"name"`
    Website string `json:"website"`
}

var Artists []Artist

func GetArtist(id string) *Artist {
	for _, artist := range Artists {
		if artist.GetID() == id {
			return &artist
		}
	}
	return nil
}

// GETTERS

func (artist Artist) GetID() string {
	return artist.ID
}

func (artist Artist) GetName() string {
	return artist.Name
}

func (artist Artist) GetWebsite() string {
	return artist.Website
}

// SETTERS

func (artist Artist) SetID(id string) error {
	artist.ID = id
	return nil
}

func (artist Artist) SetName(name string) error {
	artist.Name = name
	return nil
}

func (artist Artist) SetWebsite(website string) error {
	artist.Website = website
	return nil
}

// DATABASE

func (artist Artist) PushToDB(db *sqlx.DB) {
	// fmt.Printf("Pushing artist [%s] to database...", artist.Name)

	db.MustExec(
        "INSERT INTO artists (id, name, website) "+
        "VALUES ($1, $2, $3) "+
        "ON CONFLICT (id) "+
        "DO UPDATE SET name=$2, website=$3",
		artist.ID,
		artist.Name,
		artist.Website,
	)

	// fmt.Printf("done!\n")
}

func PullAllArtists(db *sqlx.DB) ([]Artist, error) {
	artists := []Artist{}

	rows, err := db.Query("SELECT id, name, website FROM artists")
	if err != nil {
		return nil, err
	}

	for rows.Next() {
		var artist = Artist{}

		err = rows.Scan(
            &artist.ID,
            &artist.Name,
            &artist.Website,
        )
		if err != nil {
			return nil, err
		}

		artists = append(artists, artist)
	}

	return artists, nil
}

// HTTP HANDLERS

func ServeArtist() http.Handler {
    return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
        if r.URL.Path == "/" {
            http.NotFound(w, r)
            return
        }

        type (
            creditJSON struct {
                Role    string  `json:"role"`
                Primary bool    `json:"primary"`
            }
            artistJSON struct {
                Artist
                Credits map[string]creditJSON `json:"credits"`
            }
        )
        var res = artistJSON{}

        res.ID = r.URL.Path[1:]
        var artist = GetArtist(res.ID)
        if artist == nil {
            http.NotFound(w, r)
            return
        }
        res.Name = artist.Name
        res.Website = artist.Website
        res.Credits = make(map[string]creditJSON)

        for _, release := range Releases {
            for _, credit := range release.Credits {
                if credit.Artist.ID != res.ID {
                    continue
                }
                res.Credits[release.ID] = creditJSON{
                    Role: credit.Role,
                    Primary: credit.Primary,
                }
            }
        }

        jsonBytes, err := json.Marshal(res)
        if err != nil {
            http.Error(w, http.StatusText(http.StatusInternalServerError), http.StatusInternalServerError)
            return
        }

        w.Header().Add("Content-Type", "application/json")
        w.WriteHeader(http.StatusOK)
        w.Write(jsonBytes)
    })
}