add my own session manager

sesh/vendor/github.com/gdamore/tcell/v2/style.go

@@ -0,0 +1,176 @@
+// Copyright 2022 The TCell Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use file except in compliance with the License.
+// You may obtain a copy of the license at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package tcell
+
+// Style represents a complete text style, including both foreground color,
+// background color, and additional attributes such as "bold" or "underline".
+//
+// Note that not all terminals can display all colors or attributes, and
+// many might have specific incompatibilities between specific attributes
+// and color combinations.
+//
+// To use Style, just declare a variable of its type.
+type Style struct {
+	fg    Color
+	bg    Color
+	attrs AttrMask
+	url   string
+	urlId string
+}
+
+// StyleDefault represents a default style, based upon the context.
+// It is the zero value.
+var StyleDefault Style
+
+// styleInvalid is just an arbitrary invalid style used internally.
+var styleInvalid = Style{attrs: AttrInvalid}
+
+// Foreground returns a new style based on s, with the foreground color set
+// as requested.  ColorDefault can be used to select the global default.
+func (s Style) Foreground(c Color) Style {
+	return Style{
+		fg:    c,
+		bg:    s.bg,
+		attrs: s.attrs,
+		url:   s.url,
+		urlId: s.urlId,
+	}
+}
+
+// Background returns a new style based on s, with the background color set
+// as requested.  ColorDefault can be used to select the global default.
+func (s Style) Background(c Color) Style {
+	return Style{
+		fg:    s.fg,
+		bg:    c,
+		attrs: s.attrs,
+		url:   s.url,
+		urlId: s.urlId,
+	}
+}
+
+// Decompose breaks a style up, returning the foreground, background,
+// and other attributes.  The URL if set is not included.
+func (s Style) Decompose() (fg Color, bg Color, attr AttrMask) {
+	return s.fg, s.bg, s.attrs
+}
+
+func (s Style) setAttrs(attrs AttrMask, on bool) Style {
+	if on {
+		return Style{
+			fg:    s.fg,
+			bg:    s.bg,
+			attrs: s.attrs | attrs,
+			url:   s.url,
+			urlId: s.urlId,
+		}
+	}
+	return Style{
+		fg:    s.fg,
+		bg:    s.bg,
+		attrs: s.attrs &^ attrs,
+		url:   s.url,
+		urlId: s.urlId,
+	}
+}
+
+// Normal returns the style with all attributes disabled.
+func (s Style) Normal() Style {
+	return Style{
+		fg: s.fg,
+		bg: s.bg,
+	}
+}
+
+// Bold returns a new style based on s, with the bold attribute set
+// as requested.
+func (s Style) Bold(on bool) Style {
+	return s.setAttrs(AttrBold, on)
+}
+
+// Blink returns a new style based on s, with the blink attribute set
+// as requested.
+func (s Style) Blink(on bool) Style {
+	return s.setAttrs(AttrBlink, on)
+}
+
+// Dim returns a new style based on s, with the dim attribute set
+// as requested.
+func (s Style) Dim(on bool) Style {
+	return s.setAttrs(AttrDim, on)
+}
+
+// Italic returns a new style based on s, with the italic attribute set
+// as requested.
+func (s Style) Italic(on bool) Style {
+	return s.setAttrs(AttrItalic, on)
+}
+
+// Reverse returns a new style based on s, with the reverse attribute set
+// as requested.  (Reverse usually changes the foreground and background
+// colors.)
+func (s Style) Reverse(on bool) Style {
+	return s.setAttrs(AttrReverse, on)
+}
+
+// Underline returns a new style based on s, with the underline attribute set
+// as requested.
+func (s Style) Underline(on bool) Style {
+	return s.setAttrs(AttrUnderline, on)
+}
+
+// StrikeThrough sets strikethrough mode.
+func (s Style) StrikeThrough(on bool) Style {
+	return s.setAttrs(AttrStrikeThrough, on)
+}
+
+// Attributes returns a new style based on s, with its attributes set as
+// specified.
+func (s Style) Attributes(attrs AttrMask) Style {
+	return Style{
+		fg:    s.fg,
+		bg:    s.bg,
+		attrs: attrs,
+		url:   s.url,
+		urlId: s.urlId,
+	}
+}
+
+// Url returns a style with the Url set.  If the provided Url is not empty,
+// and the terminal supports it, text will typically be marked up as a clickable
+// link to that Url.  If the Url is empty, then this mode is turned off.
+func (s Style) Url(url string) Style {
+	return Style{
+		fg:    s.fg,
+		bg:    s.bg,
+		attrs: s.attrs,
+		url:   url,
+		urlId: s.urlId,
+	}
+}
+
+// UrlId returns a style with the UrlId set. If the provided UrlId is not empty,
+// any marked up Url with this style will be given the UrlId also. If the
+// terminal supports it, any text with the same UrlId will be grouped as if it
+// were one Url, even if it spans multiple lines.
+func (s Style) UrlId(id string) Style {
+	return Style{
+		fg:    s.fg,
+		bg:    s.bg,
+		attrs: s.attrs,
+		url:   s.url,
+		urlId: "id=" + id,
+	}
+}