fix(caldav): make sure colors are correctly saved and returned

Resolves https://community.vikunja.io/t/caldav-sync-tasks-org-strips-colour-and-end-date-values/2753/2

(cherry picked from commit ffcc48ec871f50c6732eb2f2cf1a49d41e7f47fe)

pkg/caldav/caldav.go

@@ -92,7 +92,8 @@ func getCaldavColor(color string) (caldavcolor string) {
 	return `
 X-APPLE-CALENDAR-COLOR:` + color + `
 X-OUTLOOK-COLOR:` + color + `
-X-FUNAMBOL-COLOR:` + color
+X-FUNAMBOL-COLOR:` + color + `
+COLOR:` + color
 }
 
 func formatDuration(duration time.Duration) string {

pkg/caldav/caldav_test.go

@@ -64,6 +64,7 @@ PRODID:-//RandomProdID which is not random//EN
 X-APPLE-CALENDAR-COLOR:#ffffffFF
 X-OUTLOOK-COLOR:#ffffffFF
 X-FUNAMBOL-COLOR:#ffffffFF
+COLOR:#ffffffFF
 BEGIN:VTODO
 UID:randommduid
 DTSTAMP:20181201T011204Z
@@ -71,6 +72,7 @@ SUMMARY:Todo #1
 X-APPLE-CALENDAR-COLOR:#affffeFF
 X-OUTLOOK-COLOR:#affffeFF
 X-FUNAMBOL-COLOR:#affffeFF
+COLOR:#affffeFF
 DESCRIPTION:Lorem Ipsum\nDolor sit amet
 LAST-MODIFIED:00010101T000000Z
 END:VTODO
@@ -241,6 +243,7 @@ PRODID:-//RandomProdID which is not random//EN
 X-APPLE-CALENDAR-COLOR:#ffffffFF
 X-OUTLOOK-COLOR:#ffffffFF
 X-FUNAMBOL-COLOR:#ffffffFF
+COLOR:#ffffffFF
 BEGIN:VTODO
 UID:randommduid
 DTSTAMP:20181201T011204Z
@@ -248,6 +251,7 @@ SUMMARY:Todo #1
 X-APPLE-CALENDAR-COLOR:#affffeFF
 X-OUTLOOK-COLOR:#affffeFF
 X-FUNAMBOL-COLOR:#affffeFF
+COLOR:#affffeFF
 CATEGORIES:label1,label2
 LAST-MODIFIED:00010101T000000Z
 END:VTODO

pkg/caldav/parsing.go

@@ -30,6 +30,160 @@ import (
 	ics "github.com/arran4/golang-ical"
 )
 
+var cssColorsToHex map[string]string
+
+func init() {
+	cssColorsToHex = map[string]string{
+		"aliceblue":            "f0f8ff",
+		"antiquewhite":         "faebd7",
+		"aqua":                 "00ffff",
+		"aquamarine":           "7fffd4",
+		"azure":                "f0ffff",
+		"beige":                "f5f5dc",
+		"bisque":               "ffe4c4",
+		"black":                "000000",
+		"blanchedalmond":       "ffebcd",
+		"blue":                 "0000ff",
+		"blueviolet":           "8a2be2",
+		"brown":                "a52a2a",
+		"burlywood":            "deb887",
+		"cadetblue":            "5f9ea0",
+		"chartreuse":           "7fff00",
+		"chocolate":            "d2691e",
+		"coral":                "ff7f50",
+		"cornflowerblue":       "6495ed",
+		"cornsilk":             "fff8dc",
+		"crimson":              "dc143c",
+		"cyan":                 "00ffff",
+		"darkblue":             "00008b",
+		"darkcyan":             "008b8b",
+		"darkgoldenrod":        "b8860b",
+		"darkgray":             "a9a9a9",
+		"darkgreen":            "006400",
+		"darkgrey":             "a9a9a9",
+		"darkkhaki":            "bdb76b",
+		"darkmagenta":          "8b008b",
+		"darkolivegreen":       "556b2f",
+		"darkorange":           "ff8c00",
+		"darkorchid":           "9932cc",
+		"darkred":              "8b0000",
+		"darksalmon":           "e9967a",
+		"darkseagreen":         "8fbc8f",
+		"darkslateblue":        "483d8b",
+		"darkslategray":        "2f4f4f",
+		"darkslategrey":        "2f4f4f",
+		"darkturquoise":        "00ced1",
+		"darkviolet":           "9400d3",
+		"deeppink":             "ff1493",
+		"deepskyblue":          "00bfff",
+		"dimgray":              "696969",
+		"dimgrey":              "696969",
+		"dodgerblue":           "1e90ff",
+		"firebrick":            "b22222",
+		"floralwhite":          "fffaf0",
+		"forestgreen":          "228b22",
+		"fuchsia":              "ff00ff",
+		"gainsboro":            "dcdcdc",
+		"ghostwhite":           "f8f8ff",
+		"gold":                 "ffd700",
+		"goldenrod":            "daa520",
+		"gray":                 "808080",
+		"green":                "008000",
+		"greenyellow":          "adff2f",
+		"grey":                 "808080",
+		"honeydew":             "f0fff0",
+		"hotpink":              "ff69b4",
+		"indianred":            "cd5c5c",
+		"indigo":               "4b0082",
+		"ivory":                "fffff0",
+		"khaki":                "f0e68c",
+		"lavender":             "e6e6fa",
+		"lavenderblush":        "fff0f5",
+		"lawngreen":            "7cfc00",
+		"lemonchiffon":         "fffacd",
+		"lightblue":            "add8e6",
+		"lightcoral":           "f08080",
+		"lightcyan":            "e0ffff",
+		"lightgoldenrodyellow": "fafad2",
+		"lightgray":            "d3d3d3",
+		"lightgreen":           "90ee90",
+		"lightgrey":            "d3d3d3",
+		"lightpink":            "ffb6c1",
+		"lightsalmon":          "ffa07a",
+		"lightseagreen":        "20b2aa",
+		"lightskyblue":         "87cefa",
+		"lightslategray":       "778899",
+		"lightslategrey":       "778899",
+		"lightsteelblue":       "b0c4de",
+		"lightyellow":          "ffffe0",
+		"lime":                 "00ff00",
+		"limegreen":            "32cd32",
+		"linen":                "faf0e6",
+		"magenta":              "ff00ff",
+		"maroon":               "800000",
+		"mediumaquamarine":     "66cdaa",
+		"mediumblue":           "0000cd",
+		"mediumorchid":         "ba55d3",
+		"mediumpurple":         "9370db",
+		"mediumseagreen":       "3cb371",
+		"mediumslateblue":      "7b68ee",
+		"mediumspringgreen":    "00fa9a",
+		"mediumturquoise":      "48d1cc",
+		"mediumvioletred":      "c71585",
+		"midnightblue":         "191970",
+		"mintcream":            "f5fffa",
+		"mistyrose":            "ffe4e1",
+		"moccasin":             "ffe4b5",
+		"navajowhite":          "ffdead",
+		"navy":                 "000080",
+		"oldlace":              "fdf5e6",
+		"olive":                "808000",
+		"olivedrab":            "6b8e23",
+		"orange":               "ffa500",
+		"orangered":            "ff4500",
+		"orchid":               "da70d6",
+		"palegoldenrod":        "eee8aa",
+		"palegreen":            "98fb98",
+		"paleturquoise":        "afeeee",
+		"palevioletred":        "db7093",
+		"papayawhip":           "ffefd5",
+		"peachpuff":            "ffdab9",
+		"peru":                 "cd853f",
+		"pink":                 "ffc0cb",
+		"plum":                 "dda0dd",
+		"powderblue":           "b0e0e6",
+		"purple":               "800080",
+		"red":                  "ff0000",
+		"rosybrown":            "bc8f8f",
+		"royalblue":            "4169e1",
+		"saddlebrown":          "8b4513",
+		"salmon":               "fa8072",
+		"sandybrown":           "f4a460",
+		"seagreen":             "2e8b57",
+		"seashell":             "fff5ee",
+		"sienna":               "a0522d",
+		"silver":               "c0c0c0",
+		"skyblue":              "87ceeb",
+		"slateblue":            "6a5acd",
+		"slategray":            "708090",
+		"slategrey":            "708090",
+		"snow":                 "fffafa",
+		"springgreen":          "00ff7f",
+		"steelblue":            "4682b4",
+		"tan":                  "d2b48c",
+		"teal":                 "008080",
+		"thistle":              "d8bfd8",
+		"tomato":               "ff6347",
+		"turquoise":            "40e0d0",
+		"violet":               "ee82ee",
+		"wheat":                "f5deb3",
+		"white":                "ffffff",
+		"whitesmoke":           "f5f5f5",
+		"yellow":               "ffff00",
+		"yellowgreen":          "9acd32",
+	}
+}
+
 func GetCaldavTodosForTasks(project *models.ProjectWithTasksAndBuckets, projectTasks []*models.TaskWithComments) string {
 
 	// Make caldav todos from Vikunja todos
@@ -90,6 +244,27 @@ func GetCaldavTodosForTasks(project *models.ProjectWithTasksAndBuckets, projectT
 	return ParseTodos(caldavConfig, caldavtodos)
 }
 
+func getHexColorFromCaldavColor(caldavColor string) string {
+	if caldavColor == "" {
+		return ""
+	}
+
+	if caldavColor[:1] == "#" {
+		caldavColor = strings.TrimPrefix(caldavColor, "#")
+		if len(caldavColor) > 6 {
+			caldavColor = caldavColor[:6]
+		}
+		return caldavColor
+	}
+
+	hexColor, has := cssColorsToHex[caldavColor]
+	if !has {
+		return ""
+	}
+
+	return hexColor
+}
+
 func ParseTaskFromVTODO(content string) (vTask *models.Task, err error) {
 	parsed, err := ics.ParseCalendar(strings.NewReader(content))
 	if err != nil {
@@ -104,12 +279,26 @@ func ParseTaskFromVTODO(content string) (vTask *models.Task, err error) {
 	}
 	// We put the vTodo details in a map to be able to handle them more easily
 	task := make(map[string]ics.IANAProperty)
+
 	var relations []ics.IANAProperty
+	var color string
 	for _, c := range vTodo.UnknownPropertiesIANAProperties() {
 		task[c.IANAToken] = c
 		if strings.HasPrefix(c.IANAToken, "RELATED-TO") {
 			relations = append(relations, c)
 		}
+		if c.IANAToken == "X-APPLE-CALENDAR-COLOR" {
+			color = c.Value
+		}
+		if c.IANAToken == "X-OUTLOOK-COLOR" {
+			color = c.Value
+		}
+		if c.IANAToken == "X-FUNAMBOL-COLOR" {
+			color = c.Value
+		}
+		if c.IANAToken == "COLOR" {
+			color = c.Value
+		}
 	}
 
 	// Parse the priority
@@ -150,6 +339,7 @@ func ParseTaskFromVTODO(content string) (vTask *models.Task, err error) {
 		Updated:     caldavTimeToTimestamp(task["DTSTAMP"]),
 		StartDate:   caldavTimeToTimestamp(task["DTSTART"]),
 		DoneAt:      caldavTimeToTimestamp(task["COMPLETED"]),
+		HexColor:    getHexColorFromCaldavColor(color),
 	}
 
 	for _, c := range relations {

pkg/caldav/parsing_test.go

@@ -353,6 +353,142 @@ END:VCALENDAR`,
 				},
 			},
 		},
+		{
+			name: "with apple hex color",
+			args: args{content: `BEGIN:VCALENDAR
+VERSION:2.0
+METHOD:PUBLISH
+X-PUBLISHED-TTL:PT4H
+X-WR-CALNAME:test
+PRODID:-//RandomProdID which is not random//EN
+BEGIN:VTODO
+X-APPLE-CALENDAR-COLOR:#affffeFF
+END:VTODO
+END:VCALENDAR`,
+			},
+			wantVTask: &models.Task{
+				HexColor: "affffe",
+			},
+		},
+		{
+			name: "with apple css color",
+			args: args{content: `BEGIN:VCALENDAR
+VERSION:2.0
+METHOD:PUBLISH
+X-PUBLISHED-TTL:PT4H
+X-WR-CALNAME:test
+PRODID:-//RandomProdID which is not random//EN
+BEGIN:VTODO
+X-APPLE-CALENDAR-COLOR:mediumslateblue
+END:VTODO
+END:VCALENDAR`,
+			},
+			wantVTask: &models.Task{
+				HexColor: "7b68ee",
+			},
+		},
+		{
+			name: "with outlook hex color",
+			args: args{content: `BEGIN:VCALENDAR
+VERSION:2.0
+METHOD:PUBLISH
+X-PUBLISHED-TTL:PT4H
+X-WR-CALNAME:test
+PRODID:-//RandomProdID which is not random//EN
+BEGIN:VTODO
+X-OUTLOOK-COLOR:#affffeFF
+END:VTODO
+END:VCALENDAR`,
+			},
+			wantVTask: &models.Task{
+				HexColor: "affffe",
+			},
+		},
+		{
+			name: "with outlook css color",
+			args: args{content: `BEGIN:VCALENDAR
+VERSION:2.0
+METHOD:PUBLISH
+X-PUBLISHED-TTL:PT4H
+X-WR-CALNAME:test
+PRODID:-//RandomProdID which is not random//EN
+BEGIN:VTODO
+X-OUTLOOK-COLOR:mediumslateblue
+END:VTODO
+END:VCALENDAR`,
+			},
+			wantVTask: &models.Task{
+				HexColor: "7b68ee",
+			},
+		},
+		{
+			name: "with funambol hex color",
+			args: args{content: `BEGIN:VCALENDAR
+VERSION:2.0
+METHOD:PUBLISH
+X-PUBLISHED-TTL:PT4H
+X-WR-CALNAME:test
+PRODID:-//RandomProdID which is not random//EN
+BEGIN:VTODO
+X-FUNAMBOL-COLOR:#affffeFF
+END:VTODO
+END:VCALENDAR`,
+			},
+			wantVTask: &models.Task{
+				HexColor: "affffe",
+			},
+		},
+		{
+			name: "with funambol css color",
+			args: args{content: `BEGIN:VCALENDAR
+VERSION:2.0
+METHOD:PUBLISH
+X-PUBLISHED-TTL:PT4H
+X-WR-CALNAME:test
+PRODID:-//RandomProdID which is not random//EN
+BEGIN:VTODO
+X-FUNAMBOL-COLOR:mediumslateblue
+END:VTODO
+END:VCALENDAR`,
+			},
+			wantVTask: &models.Task{
+				HexColor: "7b68ee",
+			},
+		},
+		{
+			name: "with hex color",
+			args: args{content: `BEGIN:VCALENDAR
+VERSION:2.0
+METHOD:PUBLISH
+X-PUBLISHED-TTL:PT4H
+X-WR-CALNAME:test
+PRODID:-//RandomProdID which is not random//EN
+BEGIN:VTODO
+COLOR:#affffeFF
+END:VTODO
+END:VCALENDAR`,
+			},
+			wantVTask: &models.Task{
+				HexColor: "affffe",
+			},
+		},
+		{
+			name: "with css color",
+			args: args{content: `BEGIN:VCALENDAR
+VERSION:2.0
+METHOD:PUBLISH
+X-PUBLISHED-TTL:PT4H
+X-WR-CALNAME:test
+PRODID:-//RandomProdID which is not random//EN
+BEGIN:VTODO
+COLOR:mediumslateblue
+END:VTODO
+END:VCALENDAR`,
+			},
+			wantVTask: &models.Task{
+				HexColor: "7b68ee",
+			},
+		},
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {