package db

import (
    "fmt"
    "path"
    "errors"

    "gorm.io/gorm"
    // "gorm.io/gorm/logger"
    "gorm.io/driver/sqlite"
    log "github.com/sirupsen/logrus"

    "reichard.io/imagini/internal/config"
    "reichard.io/imagini/internal/models"
)

type DBManager struct {
    db  *gorm.DB
}

func NewMgr(c *config.Config) *DBManager {
    gormConfig := &gorm.Config{
        PrepareStmt: true,
        // Logger: logger.Default.LogMode(logger.Silent),
    }

    // Create manager
    dbm := &DBManager{}

    if c.DBType == "SQLite" {
        dbLocation := path.Join(c.ConfigPath, "imagini.db")
        dbm.db, _ = gorm.Open(sqlite.Open(dbLocation), gormConfig)
    } else {
        log.Fatal("Unsupported Database")
    }

    // Initialize database
    dbm.db.AutoMigrate(&models.ServerSetting{})
    dbm.db.AutoMigrate(&models.Device{})
    dbm.db.AutoMigrate(&models.User{})
    dbm.db.AutoMigrate(&models.MediaItem{})
    dbm.db.AutoMigrate(&models.Tag{})
    dbm.db.AutoMigrate(&models.Album{})

    // Determine whether to bootstrap
    var count int64
    dbm.db.Model(&models.User{}).Count(&count)
    if count == 0 {
        dbm.bootstrapDatabase()
    }

    return dbm
}

func (dbm *DBManager) bootstrapDatabase() {
    log.Info("[query] Bootstrapping database.")
    err := dbm.CreateUser(&models.User{
        Username: "admin",
        Password: "admin",
        AuthType: "Local",
    })

    if err != nil {
        log.Fatal("[query] Unable to bootstrap database.")
    }
}

func (dbm *DBManager) QueryBuilder(dest interface{}, params []byte) (int64, error) {
    // TODO:
    //  - Where Filters
    //  - Sort Filters
    //  - Paging Filters

    objType := fmt.Sprintf("%T", dest)
    if objType == "*[]models.MediaItem" {
        // TODO: Validate MediaItem Type
    } else {
        // Return Error
        return 0, errors.New("Invalid type")
    }

    var count int64
    err := dbm.db.Find(dest).Count(&count).Error;
    return count, err

    // Paging:
    //  - Regular Pagination:
    //      - /api/v1/MediaItems?page[limit]=50&page=2
    //  - Meta Count Only
    //      - /api/v1/MediaItems?page[limit]=0

    // Sorting:
    //  - Ascending Sort:
    //      - /api/v1/MediaItems?sort=created_at
    //  - Descending Sort:
    //      - /api/v1/MediaItems?sort=-created_at

    // Filters:
    //  - Greater Than / Less Than (created_at, updated_at, exif_date)
    //      - /api/v1/MediaItems?filter[created_at]>=2020-01-01&filter[created_at]<=2021-01-01
    //  - Long / Lat Range (latitude, longitude)
    //      - /api/v1/MediaItems?filter[latitude]>=71.1827&filter[latitude]<=72.0000&filter[longitude]>=100.000&filter[longitude]<=101.0000
    //  - Image / Video (media_type)
    //      - /api/v1/MediaItems?filter[media_type]=Image
    //  - Tags (tags)
    //      - /api/v1/MediaItems?filter[tags]=id1,id2,id3
    //  - Albums (albums)
    //      - /api/v1/MediaItems?filter[albums]=id1
}