package music

import (
	"errors"
	"fmt"
	"strings"
	"time"

	"github.com/jmoiron/sqlx"
)

type ReleaseType string

const (
    Single      ReleaseType = "Single"
    Album       ReleaseType = "Album"
    EP          ReleaseType = "EP"
    Compilation ReleaseType = "Compilation"
)

type Release struct {
	id              string
	title           string
	releaseType     ReleaseType
	releaseDate     time.Time
	artwork         string
	buyname         string
	buylink         string
	links           []Link
	description     string
	credits         []Credit
	tracks          []Track
}

var Releases []Release;

// GETTERS

func (release Release) GetID() string {
    return release.id
}

func (release Release) GetTitle() string {
    return release.title
}

func (release Release) GetType() ReleaseType {
    return release.releaseType
}

func (release Release) GetReleaseDate() time.Time {
    return release.releaseDate
}

func (release Release) GetArtwork() string {
    if release.artwork == "" {
        return "/img/music-artwork/default.png"
    }
    return release.artwork
}

func (release Release) GetBuyName() string {
    return release.buyname
}

func (release Release) GetBuyLink() string {
    return release.buylink
}

func (release Release) GetLinks() []Link {
    return release.links
}

func (release Release) GetDescription() string {
    return release.description
}

func (release Release) GetCredits() []Credit {
    return release.credits
}

func (release Release) GetTracks() []Track {
    return release.tracks
}

// SETTERS

func (release Release) SetID(id string) error {
    // TODO: update DB
    release.id = id
    return nil
}

func (release Release) SetTitle(title string) error {
    // TODO: update DB
    release.title = title
    return nil
}

func (release Release) SetType(releaseType ReleaseType) error {
    // TODO: update DB
    release.releaseType = releaseType
    return nil
}

func (release Release) SetReleaseDate(releaseDate time.Time) error {
    // TODO: update DB
    release.releaseDate = releaseDate
    return nil
}

func (release Release) SetArtwork(artwork string) error {
    // TODO: update DB
    release.artwork = artwork
    return nil
}

func (release Release) SetBuyName(buyname string) error {
    // TODO: update DB
    release.buyname = buyname
    return nil
}

func (release Release) SetBuyLink(buylink string) error {
    // TODO: update DB
    release.buylink = buylink
    return nil
}

func (release Release) SetLinks(links []Link) error {
    // TODO: update DB
    release.links = links
    return nil
}

func (release Release) SetDescription(description string) error {
    // TODO: update DB
    release.description = description
    return nil
}

func (release Release) SetCredits(credits []Credit) error {
    // TODO: update DB
    release.credits = credits
    return nil
}

func (release Release) SetTracks(tracks []Track) error {
    // TODO: update DB
    release.tracks = tracks
    return nil
}

// MISC

func GetRelease(id string) *Release {
    for _, release := range Releases {
        if release.GetID() == id {
            return &release
        }
    }
    return nil
}

func (release Release) PrintReleaseDate() string {
    return release.releaseDate.Format("02 January 2006")
}

func (release Release) GetReleaseYear() int {
    return release.releaseDate.Year()
}

func (release Release) IsSingle() bool {
    return len(release.tracks) == 1;
}

func (release Release) IsReleased() bool {
    return release.releaseDate.Before(time.Now())
}

func (release Release) GetUniqueArtists(only_primary bool) []Artist {
    var artists = []Artist{}

    for _, credit := range release.credits {
        if only_primary && !credit.primary {
            continue
        }

        exists := false
        for _, a := range artists {
            if a.id == credit.artist.id {
                exists = true
                break
            }
        }

        if exists {
            continue
        }

        artists = append(artists, *credit.artist)
    }

    return artists
}

func (release Release) GetUniqueArtistNames(only_primary bool) []string {
    var names = []string{}
    for _, artist := range release.GetUniqueArtists(only_primary) {
        names = append(names, artist.GetName())
    }

    return names
}

func (release Release) PrintArtists(only_primary bool, ampersand bool) string {
    names := release.GetUniqueArtistNames(only_primary)

    if len(names) == 0 {
        return "Unknown Artist"
    } else if len(names) == 1 {
        return names[0]
    }

    if ampersand {
        res := strings.Join(names[:len(names)-1], ", ")
        res += " & " + names[len(names)-1]
        return res
    } else {
        return strings.Join(names[:], ", ")
    }
}

// DATABASE

func (release Release) PushToDB(db *sqlx.DB) error {
    // fmt.Printf("Pushing release [%s] to database...", release.id)

    tx, err := db.Begin()
    if err != nil {
        return errors.New(fmt.Sprintf("Failed to initiate transaction: %s", err))
    }

    _, err = tx.Exec("INSERT INTO musicreleases (id, title, type, release_date, artwork, buyname, buylink) VALUES ($1, $2, $3, $4, $5, $6, $7) "+
    "ON CONFLICT (id) DO UPDATE SET title=$2, type=$3, release_date=$4, artwork=$5, buyname=$6, buylink=$7",
    release.id, release.title, release.releaseType, release.releaseDate.Format("2-Jan-2006"), release.artwork, release.buyname, release.buylink)

    for _, link := range release.links {
        _, err = tx.Exec(
            "INSERT INTO musiclinks (release, name, url) "+
            "VALUES ($1, $2, $3) "+
            "ON CONFLICT (release, name) "+
            "DO UPDATE SET url=$3 ",
            release.id,
            link.name,
            link.url,
        )
        if err != nil {
            return errors.New(fmt.Sprintf("Failed to add music link to transaction: %s", err))
        }
    }
    for _, credit := range release.credits {
        _, err = tx.Exec(
            "INSERT INTO musiccredits (release, artist, role, is_primary) "+
            "VALUES ($1, $2, $3, $4) "+
            "ON CONFLICT (release, artist) "+
            "DO UPDATE SET role=$3, is_primary=$4",
            release.id,
            credit.artist.id,
            credit.role,
            credit.primary,
        )
        if err != nil {
            return errors.New(fmt.Sprintf("Failed to add music credit to transaction: %s", err))
        }
    }
    for _, track := range release.tracks {
        _, err = tx.Exec(
            "INSERT INTO musictracks (release, number, title, description, lyrics, preview_url) "+
            "VALUES ($1, $2, $3, $4, $5, $6) "+
            "ON CONFLICT (release, number) "+
            "DO UPDATE SET title=$3, description=$4, lyrics=$5, preview_url=$6",
            release.id,
            track.number,
            track.title,
            track.description,
            track.lyrics,
            track.previewURL,
        )
        if err != nil {
            return errors.New(fmt.Sprintf("Failed to add music track to transaction: %s", err))
        }
    }

    err = tx.Commit()
    if err != nil {
        return errors.New(fmt.Sprintf("Failed to commit transaction: %s", err))
    }

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

    return nil
}

func (release Release) DeleteFromDB(db *sqlx.DB) error {
    // this probably doesn't need to be a transaction;
    // i just felt like making it one
    tx, err := db.Begin()
    if err != nil {
        return errors.New(fmt.Sprintf("Failed to initiate transaction: %s", err))
    }

    _, err = tx.Exec("DELETE FROM musicreleases WHERE id=$1", release.id)

    err = tx.Commit()
    if err != nil {
        return errors.New(fmt.Sprintf("Failed to commit transaction: %s", err))
    }

    return nil
}

func PullAllReleases(db *sqlx.DB) ([]Release, error) {
    releases := []Release{}

    rows, err := db.Query("SELECT id, title, description, type, release_date, artwork, buyname, buylink FROM musicreleases")
    if err != nil {
        return nil, err
    }

    for rows.Next() {
        var release = Release{}

        err = rows.Scan(
            &release.id,
            &release.title,
            &release.description,
            &release.releaseType,
            &release.releaseDate,
            &release.artwork,
            &release.buyname,
            &release.buylink,
        )
        if err != nil {
            fmt.Printf("Error while pulling a release: %s\n", err)
            continue
        }

        release.credits, err = PullReleaseCredits(db, release.id)
        if err != nil {
            fmt.Printf("Failed to pull credits for %s: %v\n", release.id, err)
        }

        release.links, err = PullReleaseLinks(db, release.id)
        if err != nil {
            fmt.Printf("Failed to pull links for %s: %v\n", release.id, err)
        }

        release.tracks, err = PullReleaseTracks(db, release.id)
        if err != nil {
            return nil, errors.New(fmt.Sprintf("error pulling tracks for %s: %v\n", release.id, err))
        }

        releases = append(releases, release)
    }

    return releases, nil
}