From d0f63fda56e88a855784e1e8a1d5db522147b2ec Mon Sep 17 00:00:00 2001
From: Eric Coissac <eric.coissac@metabarcoding.org>
Date: Wed, 28 Sep 2022 16:13:20 +0200
Subject: [PATCH] add functionalities to the expression predicate evaluations

---
 pkg/goutils/goutils.go  | 36 +++++++++++++++++++++++++++++++-----
 pkg/obiseq/predicate.go | 33 +++++++++++++++++++++++++--------
 2 files changed, 56 insertions(+), 13 deletions(-)

diff --git a/pkg/goutils/goutils.go b/pkg/goutils/goutils.go
index f4eeaab..2c4e181 100644
--- a/pkg/goutils/goutils.go
+++ b/pkg/goutils/goutils.go
@@ -7,6 +7,7 @@ import (
 	"encoding/json"
 	"io"
 	"os"
+	"reflect"
 	"sync"
 )
 
@@ -197,9 +198,34 @@ func AtomicCounter(initial ...int) func() int {
 // characters, json.Marshal should not be used. Playground of Go breaking a
 // title: https://play.golang.org/p/o2hiX0c62oN
 func JsonMarshal(i interface{}) ([]byte, error) {
-    buffer := &bytes.Buffer{}
-    encoder := json.NewEncoder(buffer)
-    encoder.SetEscapeHTML(false)
-    err := encoder.Encode(i)
-    return bytes.TrimRight(buffer.Bytes(), "\n"), err
+	buffer := &bytes.Buffer{}
+	encoder := json.NewEncoder(buffer)
+	encoder.SetEscapeHTML(false)
+	err := encoder.Encode(i)
+	return bytes.TrimRight(buffer.Bytes(), "\n"), err
 }
+
+func IsAMap(value interface{}) bool {
+	return reflect.TypeOf(value).Kind() == reflect.Map
+}
+
+func IsAnArray(value interface{}) bool {
+	return reflect.TypeOf(value).Kind() == reflect.Array
+}
+
+func IsASlice(value interface{}) bool {
+	return reflect.TypeOf(value).Kind() == reflect.Slice
+}
+
+func HasLength(value interface{}) bool {
+	return IsAMap(value) || IsAnArray(value) || IsASlice(value)
+}
+func Length(value interface{}) int {
+	l := 1
+	if HasLength(value) {
+		vc := reflect.ValueOf(value)
+		l = vc.Len()
+	}
+
+	return l
+}
\ No newline at end of file
diff --git a/pkg/obiseq/predicate.go b/pkg/obiseq/predicate.go
index fc2adce..7832c4d 100644
--- a/pkg/obiseq/predicate.go
+++ b/pkg/obiseq/predicate.go
@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"regexp"
 
+	"git.metabarcoding.org/lecasofts/go/obitools/pkg/goutils"
 	log "github.com/sirupsen/logrus"
 
 	"github.com/PaesslerAG/gval"
@@ -20,7 +21,11 @@ func (predicate1 SequencePredicate) And(predicate2 SequencePredicate) SequencePr
 		return predicate1
 	default:
 		return func(sequence *BioSequence) bool {
-			return predicate1(sequence) && predicate2(sequence)
+			if !predicate1(sequence) {
+				return false
+			}
+
+			return predicate2(sequence)
 		}
 	}
 }
@@ -33,7 +38,10 @@ func (predicate1 SequencePredicate) Or(predicate2 SequencePredicate) SequencePre
 		return predicate1
 	default:
 		return func(sequence *BioSequence) bool {
-			return predicate1(sequence) || predicate2(sequence)
+			if predicate1(sequence) {
+				return true
+			}
+			return predicate2(sequence)
 		}
 	}
 }
@@ -195,8 +203,17 @@ func IsIdIn(ids ...string) SequencePredicate {
 
 func ExpressionPredicat(expression string) SequencePredicate {
 
-	exp, err := gval.Full().NewEvaluable(expression)
-
+	lang := gval.NewLanguage(
+		gval.Full(),
+		gval.Function("len", func(args ...interface{}) (interface{}, error) {
+			length := goutils.Length(args[0])
+			return (float64)(length), nil
+		}),
+		gval.Function("ismap", func(args ...interface{}) (interface{}, error) {
+			ismap := goutils.IsAMap(args[0])
+			return ismap, nil
+		}))
+	exp, err := lang.NewEvaluable(expression)
 	if err != nil {
 		log.Fatalf("Error in the expression : %s", expression)
 	}
@@ -204,10 +221,10 @@ func ExpressionPredicat(expression string) SequencePredicate {
 	f := func(sequence *BioSequence) bool {
 		value, err := exp.EvalBool(context.Background(),
 			map[string]interface{}{
-				"annot":    sequence.Annotations(),
-				"count":    sequence.Count(),
-				"length":   sequence.Length(),
-				"sequence": sequence,
+				"annot":     sequence.Annotations(),
+				"count":     sequence.Count(),
+				"seqlength": sequence.Length(),
+				"sequence":  sequence,
 			},
 		)