archive

MovieNight/scrapedagain/common/colors.go

@@ -0,0 +1,135 @@
+package common
+
+import (
+	"errors"
+	"fmt"
+	"math/rand"
+	"regexp"
+	"strconv"
+	"strings"
+	"time"
+)
+
+func init() {
+	rand.Seed(int64(time.Now().Nanosecond()))
+}
+
+// Colors holds all the valid html color names for MovieNight
+// the values in colors must be lowercase so it matches with the color input
+// this saves from having to call strings.ToLower(color) every time to check
+var Colors = []string{
+	"aliceblue", "antiquewhite", "aqua", "aquamarine", "azure",
+	"beige", "bisque", "blanchedalmond", "blueviolet", "brown",
+	"burlywood", "cadetblue", "chartreuse", "chocolate", "coral",
+	"cornflowerblue", "cornsilk", "crimson", "cyan", "darkcyan",
+	"darkgoldenrod", "darkgray", "darkkhaki", "darkmagenta", "darkolivegreen",
+	"darkorange", "darkorchid", "darksalmon", "darkseagreen", "darkslateblue",
+	"darkslategray", "darkturquoise", "darkviolet", "deeppink", "deepskyblue",
+	"dimgray", "dodgerblue", "firebrick", "floralwhite", "forestgreen",
+	"fuchsia", "gainsboro", "ghostwhite", "gold", "goldenrod",
+	"gray", "greenyellow", "honeydew", "hotpink", "indigo",
+	"ivory", "khaki", "lavender", "lavenderblush", "lawngreen",
+	"lemonchiffon", "lightblue", "lightcoral", "lightcyan", "lightgoldenrodyellow",
+	"lightgrey", "lightgreen", "lightpink", "lightsalmon", "lightseagreen",
+	"lightskyblue", "lightslategray", "lightsteelblue", "lightyellow", "lime",
+	"limegreen", "linen", "magenta", "mediumaquamarine", "mediumorchid",
+	"mediumpurple", "mediumseagreen", "mediumslateblue", "mediumspringgreen", "mediumturquoise",
+	"mediumvioletred", "mintcream", "mistyrose", "moccasin", "navajowhite",
+	"oldlace", "olive", "olivedrab", "orange", "orangered",
+	"orchid", "palegoldenrod", "palegreen", "paleturquoise", "palevioletred",
+	"papayawhip", "peachpuff", "peru", "pink", "plum",
+	"powderblue", "purple", "rebeccapurple", "red", "rosybrown",
+	"royalblue", "saddlebrown", "salmon", "sandybrown", "seagreen",
+	"seashell", "sienna", "silver", "skyblue", "slateblue",
+	"slategray", "snow", "springgreen", "steelblue", "tan",
+	"teal", "thistle", "tomato", "turquoise", "violet",
+	"wheat", "white", "whitesmoke", "yellow", "yellowgreen",
+}
+
+var (
+	regexColor = regexp.MustCompile(`^([0-9A-Fa-f]{3}){1,2}$`)
+)
+
+// IsValidColor takes a string s and compares it against a list of css color names.
+// It also accepts hex codes in the form of #RGB and #RRGGBB
+func IsValidColor(s string) bool {
+	s = strings.TrimLeft(strings.ToLower(s), "#")
+	for _, c := range Colors {
+		if s == c {
+			return true
+		}
+	}
+
+	if regexColor.MatchString(s) {
+		r, g, b, err := hex(s)
+		if err != nil {
+			return false
+		}
+		total := float32(r + g + b)
+		return total > 0.7 && float32(b)/total < 0.7
+	}
+	return false
+}
+
+// RandomColor returns a hex color code
+func RandomColor() string {
+	var color string
+	for !IsValidColor(color) {
+		color = ""
+		for i := 0; i < 3; i++ {
+			s := strconv.FormatInt(rand.Int63n(255), 16)
+			if len(s) == 1 {
+				s = "0" + s
+			}
+			color += s
+		}
+	}
+	return "#" + color
+}
+
+// hex returns R, G, B as values
+func hex(s string) (int, int, int, error) {
+	// Make the string just the base16 numbers
+	s = strings.TrimLeft(s, "#")
+
+	if len(s) == 3 {
+		var err error
+		s, err = hexThreeToSix(s)
+		if err != nil {
+			return 0, 0, 0, err
+		}
+	}
+
+	if len(s) == 6 {
+		R64, err := strconv.ParseInt(s[0:2], 16, 32)
+		if err != nil {
+			return 0, 0, 0, err
+		}
+
+		G64, err := strconv.ParseInt(s[2:4], 16, 32)
+		if err != nil {
+			return 0, 0, 0, err
+		}
+
+		B64, err := strconv.ParseInt(s[4:6], 16, 32)
+		if err != nil {
+			return 0, 0, 0, err
+		}
+
+		return int(R64), int(G64), int(B64), nil
+	}
+	return 0, 0, 0, errors.New("incorrect format")
+}
+
+func hexThreeToSix(s string) (string, error) {
+	if len(s) != 3 {
+		return "", fmt.Errorf("%d is the incorrect length of string for convertsion", len(s))
+	}
+
+	h := ""
+	for i := 0; i < 3; i++ {
+		h += string(s[i])
+		h += string(s[i])
+	}
+	return h, nil
+}