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| 1 | +package eval |
| 2 | + |
| 3 | +import ( |
| 4 | + "regexp" |
| 5 | + "strings" |
| 6 | + "time" |
| 7 | + |
| 8 | + "github.com/maja42/goval" |
| 9 | + "go.withmatt.com/size" |
| 10 | + |
| 11 | + "github.com/ayoisaiah/f2/v2/internal/apperr" |
| 12 | +) |
| 13 | + |
| 14 | +var functions = make(map[string]goval.ExpressionFunction) |
| 15 | + |
| 16 | +var errInvalidArgs = &apperr.Error{ |
| 17 | + Message: "invalid arguments", |
| 18 | +} |
| 19 | + |
| 20 | +// ParseDuration parses a duration string. |
| 21 | +// examples: "10d", "-1.5w" or "3Y4M5d". |
| 22 | +// Add time units are "d"="D", "w"="W", "M", "y"="Y". |
| 23 | +// Adapted from: https://gist.github.com/xhit/79c9e137e1cfe332076cdda9f5e24699?permalink_comment_id=5170854#gistcomment-5170854 |
| 24 | +func parseDuration(s string) (time.Duration, error) { |
| 25 | + neg := false |
| 26 | + if s != "" && s[0] == '-' { |
| 27 | + neg = true |
| 28 | + s = s[1:] |
| 29 | + } |
| 30 | + |
| 31 | + re := regexp.MustCompile(`(\d*\.\d+|\d+)\D*`) |
| 32 | + unitMap := map[string]time.Duration{ |
| 33 | + "d": 24, |
| 34 | + "w": 7 * 24, |
| 35 | + "M": 30 * 24, |
| 36 | + "y": 365 * 24, |
| 37 | + } |
| 38 | + |
| 39 | + strs := re.FindAllString(s, -1) |
| 40 | + |
| 41 | + var sumDur time.Duration |
| 42 | + |
| 43 | + for _, str := range strs { |
| 44 | + var _hours time.Duration = 1 |
| 45 | + |
| 46 | + for unit, hours := range unitMap { |
| 47 | + if strings.Contains(str, unit) { |
| 48 | + str = strings.ReplaceAll(str, unit, "h") |
| 49 | + _hours = hours |
| 50 | + |
| 51 | + break |
| 52 | + } |
| 53 | + } |
| 54 | + |
| 55 | + dur, err := time.ParseDuration(str) |
| 56 | + if err != nil { |
| 57 | + return 0, err |
| 58 | + } |
| 59 | + |
| 60 | + sumDur += dur * _hours |
| 61 | + } |
| 62 | + |
| 63 | + if neg { |
| 64 | + sumDur = -sumDur |
| 65 | + } |
| 66 | + |
| 67 | + return sumDur, nil |
| 68 | +} |
| 69 | + |
| 70 | +func init() { |
| 71 | + functions["strlen"] = func(args ...any) (any, error) { |
| 72 | + if len(args) == 0 { |
| 73 | + return nil, errInvalidArgs |
| 74 | + } |
| 75 | + |
| 76 | + str, _ := args[0].(string) |
| 77 | + |
| 78 | + return len(str), nil |
| 79 | + } |
| 80 | + |
| 81 | + functions["dur"] = func(args ...any) (any, error) { |
| 82 | + if len(args) == 0 { |
| 83 | + return nil, errInvalidArgs |
| 84 | + } |
| 85 | + |
| 86 | + str, _ := args[0].(string) |
| 87 | + |
| 88 | + dur, err := parseDuration(str) |
| 89 | + if err != nil { |
| 90 | + return nil, err |
| 91 | + } |
| 92 | + |
| 93 | + return dur.Seconds(), nil |
| 94 | + } |
| 95 | + |
| 96 | + functions["contains"] = func(args ...any) (any, error) { |
| 97 | + if len(args) <= 1 { |
| 98 | + return nil, errInvalidArgs |
| 99 | + } |
| 100 | + |
| 101 | + str, _ := args[0].(string) |
| 102 | + substr, _ := args[1].(string) |
| 103 | + |
| 104 | + return strings.Contains(str, substr), nil |
| 105 | + } |
| 106 | + |
| 107 | + functions["size"] = func(args ...any) (any, error) { |
| 108 | + if len(args) == 0 { |
| 109 | + return nil, errInvalidArgs |
| 110 | + } |
| 111 | + |
| 112 | + str, _ := args[0].(string) |
| 113 | + |
| 114 | + // Handle Exiftool format: "26 kB" -> "26K", "1.2 MB" -> "1.2M" |
| 115 | + // Remove spaces between number and unit for compatibility with size.ParseCapacity |
| 116 | + str = strings.ReplaceAll(str, " kB", "K") |
| 117 | + str = strings.ReplaceAll(str, " MB", "M") |
| 118 | + str = strings.ReplaceAll(str, " GB", "G") |
| 119 | + str = strings.ReplaceAll(str, " TB", "T") |
| 120 | + str = strings.ReplaceAll(str, " bytes", "") |
| 121 | + |
| 122 | + s, err := size.ParseCapacity(str) |
| 123 | + if err != nil { |
| 124 | + return nil, err |
| 125 | + } |
| 126 | + |
| 127 | + //nolint:gosec // risk of overflow is acceptable |
| 128 | + return int(s.Bytes()), nil |
| 129 | + } |
| 130 | + |
| 131 | + functions["matches"] = func(args ...any) (any, error) { |
| 132 | + if len(args) <= 1 { |
| 133 | + return nil, errInvalidArgs |
| 134 | + } |
| 135 | + |
| 136 | + str, _ := args[0].(string) |
| 137 | + exp, _ := args[1].(string) |
| 138 | + |
| 139 | + reg := regexp.MustCompile(exp) |
| 140 | + |
| 141 | + return reg.MatchString(str), nil |
| 142 | + } |
| 143 | +} |
| 144 | + |
| 145 | +func Evaluate(expression string) (bool, error) { |
| 146 | + eval := goval.NewEvaluator() |
| 147 | + |
| 148 | + result, err := eval.Evaluate(expression, nil, functions) |
| 149 | + if err != nil { |
| 150 | + return false, err |
| 151 | + } |
| 152 | + |
| 153 | + r, _ := result.(bool) |
| 154 | + if !r { |
| 155 | + return false, nil |
| 156 | + } |
| 157 | + |
| 158 | + return true, nil |
| 159 | +} |
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