| 1 | // SPDX-License-Identifier: GPL-3.0-or-later |
| 2 | |
| 3 | package stm |
| 4 | |
| 5 | import ( |
| 6 | "fmt" |
| 7 | "log" |
| 8 | "reflect" |
| 9 | "strconv" |
| 10 | "strings" |
| 11 | ) |
| 12 | |
| 13 | const ( |
| 14 | fieldTagName = "stm" |
| 15 | structKey = "STMKey" |
| 16 | ) |
| 17 | |
| 18 | type ( |
| 19 | Value interface { |
| 20 | WriteTo(rv map[string]int64, key string, mul, div int) |
| 21 | } |
| 22 | ) |
| 23 | |
| 24 | // ToMap converts struct to a map[string]int64 based on 'stm' tags |
| 25 | func ToMap(s ...any) map[string]int64 { |
| 26 | rv := map[string]int64{} |
| 27 | for _, v := range s { |
| 28 | value := reflect.Indirect(reflect.ValueOf(v)) |
| 29 | toMap(value, rv, "", 1, 1) |
| 30 | } |
| 31 | return rv |
| 32 | } |
| 33 | |
| 34 | func toMap(value reflect.Value, rv map[string]int64, key string, mul, div int) { |
| 35 | if !value.IsValid() { |
| 36 | log.Panicf("value is not valid key=%s", key) |
| 37 | } |
| 38 | if value.CanInterface() { |
| 39 | val, ok := value.Interface().(Value) |
| 40 | if ok { |
| 41 | val.WriteTo(rv, key, mul, div) |
| 42 | return |
| 43 | } |
| 44 | } |
| 45 | switch value.Kind() { |
| 46 | case reflect.Pointer: |
| 47 | convertPtr(value, rv, key, mul, div) |
| 48 | case reflect.Struct: |
| 49 | convertStruct(value, rv, key) |
| 50 | case reflect.Array, reflect.Slice: |
| 51 | convertArraySlice(value, rv, key, mul, div) |
| 52 | case reflect.Map: |
| 53 | convertMap(value, rv, key, mul, div) |
| 54 | case reflect.Bool: |
| 55 | convertBool(value, rv, key) |
| 56 | case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64: |
| 57 | convertInteger(value, rv, key, mul, div) |
| 58 | case reflect.Float32, reflect.Float64: |
| 59 | convertFloat(value, rv, key, mul, div) |
| 60 | case reflect.Interface: |
| 61 | convertInterface(value, rv, key, mul, div) |
| 62 | default: |
| 63 | log.Panicf("unsupported data type: %v", value.Kind()) |
| 64 | } |
| 65 | } |
| 66 | |
| 67 | func convertPtr(value reflect.Value, rv map[string]int64, key string, mul, div int) { |
| 68 | if !value.IsNil() { |
| 69 | toMap(value.Elem(), rv, key, mul, div) |
| 70 | } |
| 71 | } |
| 72 | |
| 73 | func convertStruct(value reflect.Value, rv map[string]int64, key string) { |
| 74 | t := value.Type() |
| 75 | k := value.FieldByName(structKey) |
| 76 | if k.Kind() == reflect.String { |
| 77 | key = joinPrefix(key, k.String()) |
| 78 | } |
| 79 | for i := 0; i < t.NumField(); i++ { |
| 80 | ft := t.Field(i) |
| 81 | tag, ok := ft.Tag.Lookup(fieldTagName) |
| 82 | if !ok || ft.Name == structKey { |
| 83 | continue |
| 84 | } |
| 85 | value := value.Field(i) |
| 86 | prefix, mul, div := parseTag(tag) |
| 87 | toMap(value, rv, joinPrefix(key, prefix), mul, div) |
| 88 | } |
| 89 | } |
| 90 | |
| 91 | func convertMap(value reflect.Value, rv map[string]int64, key string, mul, div int) { |
| 92 | if value.IsNil() { |
| 93 | log.Panicf("value is nil key=%s", key) |
| 94 | } |
| 95 | for _, k := range value.MapKeys() { |
| 96 | toMap(value.MapIndex(k), rv, joinPrefix(key, k.String()), mul, div) |
| 97 | } |
| 98 | } |
| 99 | |
| 100 | func convertArraySlice(value reflect.Value, rv map[string]int64, key string, mul, div int) { |
| 101 | for i := 0; i < value.Len(); i++ { |
| 102 | toMap(value.Index(i), rv, key, mul, div) |
| 103 | } |
| 104 | } |
| 105 | |
| 106 | func convertBool(value reflect.Value, rv map[string]int64, key string) { |
| 107 | if _, ok := rv[key]; ok { |
| 108 | log.Panic("duplicate key: ", key) |
| 109 | } |
| 110 | if value.Bool() { |
| 111 | rv[key] = 1 |
| 112 | } else { |
| 113 | rv[key] = 0 |
| 114 | } |
| 115 | } |
| 116 | |
| 117 | func convertInteger(value reflect.Value, rv map[string]int64, key string, mul, div int) { |
| 118 | if _, ok := rv[key]; ok { |
| 119 | log.Panic("duplicate key: ", key) |
| 120 | } |
| 121 | intVal := value.Int() |
| 122 | rv[key] = intVal * int64(mul) / int64(div) |
| 123 | } |
| 124 | |
| 125 | func convertFloat(value reflect.Value, rv map[string]int64, key string, mul, div int) { |
| 126 | if _, ok := rv[key]; ok { |
| 127 | log.Panic("duplicate key: ", key) |
| 128 | } |
| 129 | floatVal := value.Float() |
| 130 | rv[key] = int64(floatVal * float64(mul) / float64(div)) |
| 131 | } |
| 132 | |
| 133 | func convertInterface(value reflect.Value, rv map[string]int64, key string, mul, div int) { |
| 134 | fv := reflect.ValueOf(value.Interface()) |
| 135 | toMap(fv, rv, key, mul, div) |
| 136 | } |
| 137 | |
| 138 | func joinPrefix(prefix, key string) string { |
| 139 | if prefix == "" { |
| 140 | return key |
| 141 | } |
| 142 | if key == "" { |
| 143 | return prefix |
| 144 | } |
| 145 | return prefix + "_" + key |
| 146 | } |
| 147 | |
| 148 | func parseTag(tag string) (prefix string, mul int, div int) { |
| 149 | tokens := strings.Split(tag, ",") |
| 150 | mul = 1 |
| 151 | div = 1 |
| 152 | var err error |
| 153 | switch len(tokens) { |
| 154 | case 3: |
| 155 | div, err = strconv.Atoi(tokens[2]) |
| 156 | if err != nil { |
| 157 | log.Panic(err) |
| 158 | } |
| 159 | fallthrough |
| 160 | case 2: |
| 161 | mul, err = strconv.Atoi(tokens[1]) |
| 162 | if err != nil { |
| 163 | log.Panic(err) |
| 164 | } |
| 165 | fallthrough |
| 166 | case 1: |
| 167 | prefix = tokens[0] |
| 168 | default: |
| 169 | log.Panic(fmt.Errorf("invalid tag format: %s", tag)) |
| 170 | } |
| 171 | return |
| 172 | } |