package intimate

import (
	"database/sql"
	"fmt"
	"reflect"
	"testing"
)

type Store struct {
	db *sql.DB
}

type Table struct {
	store   *Store
	name    string
	setting interface{}

	updatesql string
	selectsql string
	insertsql string
}

// const updatesql = "UPDATE %s SET %s WHERE %s = ?"

func NewStore(uri string) *Store {
	db, err := sql.Open("mysql", uri)
	if err != nil {
		panic(err)
	}
	s := &Store{db: db}
	return s
}

func (store *Store) Table(name string) *Table {
	table := &Table{store: store}
	table.name = name

	table.insertsql = `INSERT INTO ` + table.name + `(%s) values(%s)`
	table.updatesql = `UPDATE ` + table.name + ` SET %s WHERE %s = ?`

	return table
}

type Queue struct {
	table *Table
	obj   reflect.Type
}

func (t *Table) Insert(obj interface{}) error {
	ov := reflect.ValueOf(obj).Elem()
	ot := reflect.TypeOf(obj)

	fieldsql := ""
	argssql := ""

	var args []interface{}
	for i := 0; i < ov.NumField(); i++ {
		field := ov.Field(i)
		ftype := ot.Elem().Field(i)

		if fname, ok := ftype.Tag.Lookup("field"); ok {
			if flag, ok := ftype.Tag.Lookup("uid"); ok {
				if flag == "auto" {
					continue
				}
			}

			k := ftype.Type.Kind()
			if k == reflect.Ptr || k == reflect.Interface {
				if !field.IsNil() {
					felem := field.Elem()
					args = append(args, felem.Interface())
					fieldsql += fname + ","
					argssql += "?,"
				}
			} else {
				args = append(args, field.Interface())
				fieldsql += fname + ","
				argssql += "?,"
			}

		}

	}

	ssql := fmt.Sprintf(t.insertsql, fieldsql[:len(fieldsql)-1], argssql[:len(argssql)-1])
	_, err := t.store.db.Exec(ssql, args...)
	return err
}

func (t *Table) Update(obj interface{}) error {

	ov := reflect.ValueOf(obj).Elem()
	ot := reflect.TypeOf(obj)

	fieldsql := ""
	var uidname string
	var uidvalue interface{}

	var args []interface{}
	for i := 0; i < ov.NumField(); i++ {
		field := ov.Field(i)
		ftype := ot.Elem().Field(i)

		if fname, ok := ftype.Tag.Lookup("field"); ok {
			if _, ok := ftype.Tag.Lookup("uid"); ok {
				if uidvalue != nil {
					panic(fmt.Errorf("uid must unique, %s and %s", uidname, fname))
				}
				uidname = fname
				uidvalue = field.Interface()
				continue
			}

			k := ftype.Type.Kind()
			if k == reflect.Ptr || k == reflect.Interface {
				if !field.IsNil() {
					felem := field.Elem()
					args = append(args, felem.Interface())
					fieldsql += fname + " = ?,"
				}
			} else {
				args = append(args, field.Interface())
				fieldsql += fname + " = ?,"
			}

		}

	}

	if uidvalue == nil {
		panic(fmt.Errorf("update must contain `uid` tag"))
	}

	usql := fmt.Sprintf(t.updatesql, fieldsql[:len(fieldsql)-1], uidname)
	args = append(args, uidvalue)
	_, err := t.store.db.Exec(usql, args...)
	return err
}

type TSreamer struct {
	Uid    int             `field:"uid" uid:"auto"`
	Name   interface{}     `field:"name"`
	UserID *sql.NullString `field:"userid"`
	Ext    *sql.NullString `field:"ext"`
	Iface  interface{}     `field:"tag"`
}

func TestAutoStore(t *testing.T) {
	uri := "root:@tcp(127.0.0.1:4000)/test?parseTime=true&loc=Local&charset=utf8mb4&collation=utf8mb4_unicode_ci"
	store := NewStore(uri)
	streamer := &TSreamer{}

	streamer.Uid = 2
	streamer.UserID = nil
	streamer.Name = "streamer"
	streamer.Ext = &sql.NullString{String: "ext", Valid: true}
	err := store.Table("streamer").Update(streamer)
	if err != nil {
		t.Error(err)
	}
}