package orm

import (
	"fmt"
	"reflect"
	"strings"
	"time"
)

func getTableName(model Modeler) string {
	val := reflect.ValueOf(model)
	ind := reflect.Indirect(val)
	fun := val.MethodByName("TableName")
	if fun.IsValid() {
		vals := fun.Call([]reflect.Value{})
		if len(vals) > 0 {
			val := vals[0]
			if val.Kind() == reflect.String {
				return val.String()
			}
		}
	}
	return snakeString(ind.Type().Name())
}

func getPkgPath(model Modeler) string {
	val := reflect.ValueOf(model)
	return val.Type().Elem().PkgPath()
}

func getColumnName(ft int, addrField reflect.Value, sf reflect.StructField, col string) string {
	column := strings.ToLower(col)
	if column == "" {
		column = snakeString(sf.Name)
	}
	switch ft {
	case RelForeignKey, RelOneToOne:
		column = column + "_id"
	case RelManyToMany, RelReverseMany, RelReverseOne:
		column = sf.Name
	}
	return column
}

func getFieldType(val reflect.Value) (ft int, err error) {
	elm := reflect.Indirect(val)
	switch elm.Kind() {
	case reflect.Int16:
		ft = TypeSmallIntegerField
	case reflect.Int32, reflect.Int:
		ft = TypeIntegerField
	case reflect.Int64:
		ft = TypeBigIntegerField
	case reflect.Uint16:
		ft = TypePositiveSmallIntegerField
	case reflect.Uint32:
		ft = TypePositiveIntegerField
	case reflect.Uint64:
		ft = TypePositiveBigIntegerField
	case reflect.Float32, reflect.Float64:
		ft = TypeFloatField
	case reflect.Bool:
		ft = TypeBooleanField
	case reflect.String:
		ft = TypeTextField
	case reflect.Invalid:
	default:
		if elm.CanInterface() {
			if _, ok := elm.Interface().(time.Time); ok {
				ft = TypeDateTimeField
			}
		}
	}
	if ft&IsFieldType == 0 {
		err = fmt.Errorf("unsupport field type %s, may be miss setting tag", val)
	}
	return
}

func parseStructTag(data string, attrs *map[string]bool, tags *map[string]string) {
	attr := make(map[string]bool)
	tag := make(map[string]string)
	for _, v := range strings.Split(data, ";") {
		v = strings.TrimSpace(v)
		if supportTag[v] == 1 {
			attr[v] = true
		} else if i := strings.Index(v, "("); i > 0 && strings.Index(v, ")") == len(v)-1 {
			name := v[:i]
			if supportTag[name] == 2 {
				v = v[i+1 : len(v)-1]
				tag[name] = v
			}
		}
	}
	*attrs = attr
	*tags = tag
}