Fix crash and add support for content in <div> (#9)

* fix #8: better regex to remove html entities
* add opf and ncx debug
* make epub content retrieval more flexible
* fix epub content retrieval: also support html files with <div>

.github/workflows/ci.yaml

@@ -21,9 +21,29 @@ jobs:
     - name: build
       run: go build
 
+  test:
+    strategy:
+      matrix:
+        version: [1.24.9]
+        os: [ubuntu-latest]
+    name: Test
+    runs-on: ${{ matrix.os }}
+    steps:
+    - name: Set up Go ${{ matrix.os }}
+      uses: actions/setup-go@v6
+      with:
+        go-version: '${{ matrix.version }}'
+      id: go
+
+    - name: checkout
+      uses: actions/checkout@v5
+
+    - name: test
+      run: go test -cover ./...
+      
 
   golangci:
-    name: lint
+    name: Lintercheck
     runs-on: ubuntu-latest
     steps:
       - uses: actions/setup-go@v6

README.md

@@ -1,3 +1,8 @@
+[![Actions](https://github.com/tlinden/epuppy/actions/workflows/ci.yaml/badge.svg)](https://github.com/tlinden/epuppy/actions)
+[![License](https://img.shields.io/badge/license-GPL-blue.svg)](https://github.com/tlinden/epuppy/blob/master/LICENSE)
+[![Go Report Card](https://goreportcard.com/badge/github.com/tlinden/epuppy)](https://goreportcard.com/report/github.com/tlinden/epuppy)
+
+
 # epuppy - terminal epub reader
 
 This is a little TUI epub ebook reader. This is a work in progress and
@@ -27,6 +32,66 @@ long run.
 - Showing the help
 ![Screenshot](https://github.com/TLINDEN/epuppy/blob/main/.github/assets/help.png)
 
+## Usage
+
+To read an ebook, just give a filename as argument to `epuppy`.
+
+Add  the option  `-s` to  store and  use a  previously stored  reading
+progress.
+
+Sometimes you may be unhappy with the colors. Depending on your
+terminal style you can enable dark mode with `-D`, light mode is the
+default. You can also configure custom colors in a config file in
+`$HOME/.config/epuppy/confit.toml`:
+
+```toml
+# color setting for dark mode
+colordark = {
+  body = "#ffffff",
+  title = "#7cfc00",
+  chapter = "#ffff00"
+}
+
+# color setting for light mode
+colorlight = {
+  body = "#000000",
+  title = "#8470ff",
+  chapter = "#00008b"
+}
+
+# always use dark mode
+dark = true
+```
+
+There are also cases where your current terminal just doesn't have the
+capabilites for this stuff. I stumbled upon such a case during an SSH
+session from my Android phone to a FreeBSD server. For this you can
+either just disable colors with `-N` or by setting the environment
+variable `$NO_COLOR` to 1. Or you can just dump the text of the ebook
+and pipe it to some pager, e.g.:
+
+```default
+epuppy -t someebook.epub | less
+```
+
+There are also a couple of debug options etc, all options:
+
+```default
+Usage epuppy [options] <epub file>
+
+Options:
+-D --dark                enable dark mode
+-s --store-progress      remember reading position
+-n --line-numbers        add line numbers
+-c --config <file>       use config <file>
+-t --txt                 dump readable content to STDOUT
+-x --xml                 dump source xml to STDOUT
+-N --no-color            disable colors (or use $NO_COLOR env var)
+-d --debug               enable debugging
+-h --help                show help message
+-v --version             show program version
+```
+
 ## Installation
 
 The tool does not have any dependencies.  Just download the binary for
@@ -83,4 +148,4 @@ version 3.
 
 # Author
 
-Copyleft (c) 2024 Thomas von Dein
+Copyleft (c) 2025 Thomas von Dein

cmd/colors.go

@@ -1,3 +1,19 @@
+/*
+Copyright © 2025 Thomas von Dein
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program. If not, see <http://www.gnu.org/licenses/>.
+*/
 package cmd
 
 import (

cmd/config.go

@@ -1,3 +1,19 @@
+/*
+Copyright © 2025 Thomas von Dein
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program. If not, see <http://www.gnu.org/licenses/>.
+*/
 package cmd
 
 import (
@@ -16,16 +32,20 @@ import (
 )
 
 const (
-	Version string = `v0.0.3`
+	Version string = `v0.0.5`
-	Usage   string = `Usage epuppy [options] <epub file>
+	Usage   string = `This is epuppy, a terminal ui ebook viewer.
+
+Usage: epuppy [options] <epub file>
 
 Options:
 -D --dark                enable dark mode
 -s --store-progress      remember reading position
 -n --line-numbers        add line numbers
 -c --config <file>       use config <file>
+-i --cover-image         display cover image
 -t --txt                 dump readable content to STDOUT
 -x --xml                 dump source xml to STDOUT
+-N --no-color            disable colors (or use $NO_COLOR env var)
 -d --debug               enable debugging
 -h --help                show help message
 -v --version             show program version`
@@ -39,10 +59,12 @@ type Config struct {
 	LineNumbers     bool         `koanf:"line-numbers"`   // -n
 	Dump            bool         `koanf:"txt"`            // -t
 	XML             bool         `koanf:"xml"`            // -x
+	NoColor         bool         `koanf:"no-color"`       // -n
 	Config          string       `koanf:"config"`         // -c
 	ColorDark       ColorSetting `koanf:"colordark"`      // comes from config file only
 	ColorLight      ColorSetting `koanf:"colorlight"`     // comes from config file only
-
+	ShowHelp        bool         `koanf:"help"`
+	ShowCover       bool         `koanf:"cover-image"` // -i
 	Colors          Colors       // generated from user config file or internal defaults, respects dark mode
 	Document        string
 	InitialProgress int // lines
@@ -58,7 +80,6 @@ func InitConfig(output io.Writer) (*Config, error) {
 		if err != nil {
 			log.Fatalf("failed to print to output: %s", err)
 		}
-		os.Exit(0)
 	}
 
 	// parse commandline flags
@@ -69,6 +90,9 @@ func InitConfig(output io.Writer) (*Config, error) {
 	flagset.BoolP("line-numbers", "n", false, "add line numbers")
 	flagset.BoolP("txt", "t", false, "dump readable content to STDOUT")
 	flagset.BoolP("xml", "x", false, "dump xml to STDOUT")
+	flagset.BoolP("no-color", "N", false, "disable colors")
+	flagset.BoolP("cover-image", "i", false, "show cover image")
+	flagset.BoolP("help", "h", false, "show help")
 	flagset.StringP("config", "c", "", "read config from file")
 
 	if err := flagset.Parse(os.Args[1:]); err != nil {
@@ -117,8 +141,9 @@ func InitConfig(output io.Writer) (*Config, error) {
 	if len(flagset.Args()) > 0 {
 		conf.Document = flagset.Args()[0]
 	} else {
-		if !conf.Showversion {
+		if !conf.Showversion && !conf.ShowHelp {
 			flagset.Usage()
+			os.Exit(1)
 		}
 	}
 
@@ -140,6 +165,11 @@ func InitConfig(output io.Writer) (*Config, error) {
 		},
 		conf)
 
+	// disable colors if requested by command line
+	if conf.NoColor {
+		_ = os.Setenv("NO_COLOR", "1")
+	}
+
 	return conf, nil
 }
 

cmd/pager.go

@@ -1,3 +1,19 @@
+/*
+Copyright © 2025 Thomas von Dein
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program. If not, see <http://www.gnu.org/licenses/>.
+*/
 package cmd
 
 // pager setup using bubbletea
@@ -5,10 +21,13 @@ package cmd
 // https://github.com/charmbracelet/bubbletea/tree/main/examples/pager
 
 import (
+	"bytes"
 	"fmt"
+	"image"
 	"os"
 	"strings"
 
+	"github.com/blacktop/go-termimg"
 	"github.com/charmbracelet/bubbles/help"
 	"github.com/charmbracelet/bubbles/key"
 	"github.com/charmbracelet/bubbles/viewport"
@@ -52,12 +71,16 @@ type keyMap struct {
 	Right    key.Binding
 	Help     key.Binding
 	Quit     key.Binding
+	ToggleUI key.Binding
+	Pad      key.Binding
 }
 
 func (k keyMap) FullHelp() [][]key.Binding {
 	return [][]key.Binding{
-		{k.Up, k.Down, k.Left, k.Right}, // first column
+		// every item is one column
-		{k.Help, k.Quit},                // second column
+		{k.Up, k.Down, k.Left, k.Right},
+		{k.Pad}, // fake key, we use it as spacing between columns
+		{k.Help, k.Quit, k.ToggleUI},
 	}
 }
 
@@ -66,6 +89,10 @@ func (k keyMap) ShortHelp() []key.Binding {
 }
 
 var keys = keyMap{
+	Pad: key.NewBinding(
+		key.WithKeys("__"),
+		key.WithHelp("  ", ""),
+	),
 	Up: key.NewBinding(
 		key.WithKeys("up", "k"),
 		key.WithHelp("↑", "move up"),
@@ -75,11 +102,11 @@ var keys = keyMap{
 		key.WithHelp("↓", "move down"),
 	),
 	Left: key.NewBinding(
-		key.WithKeys("left", "h"),
+		key.WithKeys("left"),
 		key.WithHelp("←", "decrease text width"),
 	),
 	Right: key.NewBinding(
-		key.WithKeys("right", "l"),
+		key.WithKeys("right"),
 		key.WithHelp("→", "increase text width"),
 	),
 	Help: key.NewBinding(
@@ -90,6 +117,10 @@ var keys = keyMap{
 		key.WithKeys("q", "esc", "ctrl+c"),
 		key.WithHelp("q", "quit"),
 	),
+	ToggleUI: key.NewBinding(
+		key.WithKeys("h"),
+		key.WithHelp("h", "toggle ui"),
+	),
 }
 
 type Doc struct {
@@ -101,8 +132,10 @@ type Doc struct {
 	lastwidth    int
 	margin       int
 	marginMod    bool
+	hideUi       bool
 	meta         *Meta
 	config       *Config
+	Cover        *termimg.ImageWidget
 
 	keys keyMap
 	help help.Model
@@ -135,6 +168,8 @@ func (m Doc) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 				m.margin -= MarginStep
 				m.marginMod = true
 			}
+		case key.Matches(msg, m.keys.ToggleUI):
+			m.hideUi = !m.hideUi
 		}
 
 	case tea.WindowSizeMsg:
@@ -189,7 +224,12 @@ func (m *Doc) Rewrap() {
 
 	// wrapping has changed, update viewport and line count
 	if content != "" {
+		if m.Cover != nil {
+			cover, _ := m.Cover.Render()
+			m.viewport.SetContent(cover + "\n\n" + content)
+		} else {
 			m.viewport.SetContent(content)
+		}
 		m.meta.lines = len(strings.Split(content, "\n"))
 	}
 
@@ -212,6 +252,10 @@ func (m Doc) View() string {
 		helpView = "\n" + m.help.View(m.keys)
 	}
 
+	if m.hideUi {
+		return fmt.Sprintf("%s\n%s", m.viewport.View(), helpView)
+	}
+
 	return fmt.Sprintf("%s\n%s\n%s%s", m.headerView(), m.viewport.View(), m.footerView(), helpView)
 }
 
@@ -235,7 +279,15 @@ func max(a, b int) int {
 	return b
 }
 
-func Pager(conf *Config, title, message string) (int, error) {
+type Ebook struct {
+	Config    *Config
+	Title     string
+	Body      string
+	Cover     []byte
+	MediaType string
+}
+
+func Pager(book *Ebook) (int, error) {
 	width := 80
 	scrollto := 0
 
@@ -246,32 +298,44 @@ func Pager(conf *Config, title, message string) (int, error) {
 		}
 	}
 
-	if conf.StoreProgress {
+	if book.Config.StoreProgress {
-		scrollto = conf.InitialProgress
+		scrollto = book.Config.InitialProgress
 	}
 
-	if conf.LineNumbers {
+	if book.Config.LineNumbers {
 		catn := ""
-		for idx, line := range strings.Split(message, "\n") {
+		for idx, line := range strings.Split(book.Body, "\n") {
-			catn += fmt.Sprintf("%d: %s\n", idx, line)
+			catn += fmt.Sprintf("%4d: %s\n", idx, line)
 		}
-		message = catn
+		book.Body = catn
 	}
 
 	meta := Meta{
 		initialprogress: scrollto,
-		lines:           len(strings.Split(message, "\n")),
+		lines:           len(strings.Split(book.Body, "\n")),
+	}
+
+	doc := Doc{
+		content:      book.Body,
+		title:        book.Title,
+		initialwidth: width,
+		meta:         &meta,
+		config:       book.Config,
+		keys:         keys,
+	}
+
+	if book.MediaType != "" && book.Config.ShowCover {
+		img, _, err := image.Decode(bytes.NewReader(book.Cover))
+		if err != nil {
+			return 0, fmt.Errorf("failed to load cover image: %w", err)
+		}
+
+		doc.Cover = termimg.NewImageWidgetFromImage(img)
+		doc.Cover.SetSize(width, width).SetProtocol(termimg.Auto)
 	}
 
 	p := tea.NewProgram(
-		Doc{
+		doc,
-			content:      message,
-			title:        title,
-			initialwidth: width,
-			meta:         &meta,
-			config:       conf,
-			keys:         keys,
-		},
 		tea.WithAltScreen(),       // use the full size of the terminal in its "alternate screen buffer"
 		tea.WithMouseCellMotion(), // turn on mouse support so we can track the mouse wheel
 	)
@@ -280,7 +344,7 @@ func Pager(conf *Config, title, message string) (int, error) {
 		return 0, fmt.Errorf("could not run pager: %w", err)
 	}
 
-	if conf.Debug {
+	if book.Config.Debug {
 		fmt.Printf("scrollto: %d, last: %d, diff: %d\n",
 			scrollto, meta.currentline, scrollto-meta.currentline)
 	}

cmd/root.go

@@ -1,3 +1,19 @@
+/*
+Copyright © 2025 Thomas von Dein
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program. If not, see <http://www.gnu.org/licenses/>.
+*/
 package cmd
 
 import (
@@ -27,6 +43,15 @@ func Execute(output io.Writer) int {
 		return 0
 	}
 
+	if conf.ShowHelp {
+		_, err := fmt.Fprintln(output, Usage)
+		if err != nil {
+			return Die(fmt.Errorf("failed to print to output: %s", err))
+		}
+
+		return 0
+	}
+
 	if conf.StoreProgress {
 		progress, err := GetProgress(conf)
 		if err == nil {

cmd/store.go

@@ -1,3 +1,19 @@
+/*
+Copyright © 2025 Thomas von Dein
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program. If not, see <http://www.gnu.org/licenses/>.
+*/
 package cmd
 
 import (

cmd/view.go

@@ -1,3 +1,19 @@
+/*
+Copyright © 2025 Thomas von Dein
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program. If not, see <http://www.gnu.org/licenses/>.
+*/
 package cmd
 
 import (
@@ -6,6 +22,7 @@ import (
 	"path/filepath"
 	"strings"
 
+	"github.com/alecthomas/repr"
 	"github.com/tlinden/epuppy/pkg/epub"
 )
 
@@ -28,7 +45,11 @@ func ViewText(conf *Config) (int, error) {
 		return fmt.Println(string(data))
 	}
 
-	return Pager(conf, conf.Document, string(data))
+	return Pager(&Ebook{
+		Config: conf,
+		Title:  conf.Document,
+		Body:   string(data),
+	})
 }
 
 func ViewEpub(conf *Config) (int, error) {
@@ -37,6 +58,11 @@ func ViewEpub(conf *Config) (int, error) {
 		return 0, err
 	}
 
+	if conf.Debug {
+		repr.Println(book.Files())
+		repr.Println(book.Ncx)
+	}
+
 	buf := strings.Builder{}
 	head := strings.Builder{}
 
@@ -58,11 +84,19 @@ func ViewEpub(conf *Config) (int, error) {
 		return fmt.Println(buf.String())
 	}
 
-	return Pager(conf, head.String(), buf.String())
+	if conf.Debug {
+		return 0, nil
+	}
+
+	return Pager(&Ebook{
+		Config:    conf,
+		Title:     head.String(),
+		Body:      buf.String(),
+		Cover:     book.CoverImage,
+		MediaType: book.CoverMediaType,
+	})
 }
 
-// FIXME:  since the  switch to  book.Files() in  epub.Open() this
-// returns invalid chapter numbering
 func fetchByContent(conf *Config, buf *strings.Builder, book *epub.Book) bool {
 	chapter := 1
 	var gotbody bool

go.mod

@@ -41,12 +41,21 @@ require (
 
 require (
 	github.com/antchfx/xpath v1.3.5 // indirect
+	github.com/blacktop/go-termimg v0.1.20 // indirect
+	github.com/charmbracelet/x/mosaic v0.0.0-20250702191427-5bdfc8f2e4ff // indirect
 	github.com/fsnotify/fsnotify v1.9.0 // indirect
 	github.com/go-viper/mapstructure/v2 v2.4.0 // indirect
 	github.com/golang/groupcache v0.0.0-20210331224755-41bb18bfe9da // indirect
 	github.com/knadh/koanf/maps v0.1.2 // indirect
+	github.com/makeworld-the-better-one/dither/v2 v2.4.0 // indirect
+	github.com/mattn/go-sixel v0.0.5 // indirect
 	github.com/mitchellh/copystructure v1.2.0 // indirect
 	github.com/mitchellh/reflectwalk v1.0.2 // indirect
+	github.com/nfnt/resize v0.0.0-20180221191011-83c6a9932646 // indirect
 	github.com/pelletier/go-toml v1.9.5 // indirect
-	golang.org/x/net v0.33.0 // indirect
+	github.com/rogpeppe/go-internal v1.14.1 // indirect
+	github.com/soniakeys/quant v1.0.0 // indirect
+	golang.org/x/image v0.25.0 // indirect
+	golang.org/x/net v0.44.0 // indirect
+	golang.org/x/tools v0.37.0 // indirect
 )

go.sum

@@ -8,6 +8,8 @@ github.com/aymanbagabas/go-osc52/v2 v2.0.1 h1:HwpRHbFMcZLEVr42D4p7XBqjyuxQH5SMiE
 github.com/aymanbagabas/go-osc52/v2 v2.0.1/go.mod h1:uYgXzlJ7ZpABp8OJ+exZzJJhRNQ2ASbcXHWsFqH8hp8=
 github.com/aymanbagabas/go-udiff v0.2.0 h1:TK0fH4MteXUDspT88n8CKzvK0X9O2xu9yQjWpi6yML8=
 github.com/aymanbagabas/go-udiff v0.2.0/go.mod h1:RE4Ex0qsGkTAJoQdQQCA0uG+nAzJO/pI/QwceO5fgrA=
+github.com/blacktop/go-termimg v0.1.20 h1:+EAUc3c9hwE/fUYaqRV1BSLvAlOuLySgLTEBzxGbYK4=
+github.com/blacktop/go-termimg v0.1.20/go.mod h1:nwxrOjfFcBjtS358oIGBLfscSLnCpNdRlMVRxsnZwMU=
 github.com/charmbracelet/bubbles v0.21.0 h1:9TdC97SdRVg/1aaXNVWfFH3nnLAwOXr8Fn6u6mfQdFs=
 github.com/charmbracelet/bubbles v0.21.0/go.mod h1:HF+v6QUR4HkEpz62dx7ym2xc71/KBHg+zKwJtMw+qtg=
 github.com/charmbracelet/bubbletea v1.3.10 h1:otUDHWMMzQSB0Pkc87rm691KZ3SWa4KUlvF9nRvCICw=
@@ -22,8 +24,11 @@ github.com/charmbracelet/x/cellbuf v0.0.13-0.20250311204145-2c3ea96c31dd h1:vy0G
 github.com/charmbracelet/x/cellbuf v0.0.13-0.20250311204145-2c3ea96c31dd/go.mod h1:xe0nKWGd3eJgtqZRaN9RjMtK7xUYchjzPr7q6kcvCCs=
 github.com/charmbracelet/x/exp/golden v0.0.0-20241011142426-46044092ad91 h1:payRxjMjKgx2PaCWLZ4p3ro9y97+TVLZNaRZgJwSVDQ=
 github.com/charmbracelet/x/exp/golden v0.0.0-20241011142426-46044092ad91/go.mod h1:wDlXFlCrmJ8J+swcL/MnGUuYnqgQdW9rhSD61oNMb6U=
+github.com/charmbracelet/x/mosaic v0.0.0-20250702191427-5bdfc8f2e4ff h1:OVBKPzoa0k5ZVMoor27BReRZxER1IEDtLHXkRjaHElg=
+github.com/charmbracelet/x/mosaic v0.0.0-20250702191427-5bdfc8f2e4ff/go.mod h1:5qLP4S++M5quSc/xbvWWW8vKkgKwOqOT/IVhAas26XI=
 github.com/charmbracelet/x/term v0.2.1 h1:AQeHeLZ1OqSXhrAWpYUtZyX1T3zVxfpZuEQMIQaGIAQ=
 github.com/charmbracelet/x/term v0.2.1/go.mod h1:oQ4enTYFV7QN4m0i9mzHrViD7TQKvNEEkHUMCmsxdUg=
+github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/erikgeiser/coninput v0.0.0-20211004153227-1c3628e74d0f h1:Y/CXytFA4m6baUTXGLOoWe4PQhGxaX0KpnayAqC48p4=
@@ -47,6 +52,8 @@ github.com/knadh/koanf/v2 v2.3.0 h1:Qg076dDRFHvqnKG97ZEsi9TAg2/nFTa9hCdcSa1lvlM=
 github.com/knadh/koanf/v2 v2.3.0/go.mod h1:gRb40VRAbd4iJMYYD5IxZ6hfuopFcXBpc9bbQpZwo28=
 github.com/lucasb-eyer/go-colorful v1.2.0 h1:1nnpGOrhyZZuNyfu1QjKiUICQ74+3FNCN69Aj6K7nkY=
 github.com/lucasb-eyer/go-colorful v1.2.0/go.mod h1:R4dSotOR9KMtayYi1e77YzuveK+i7ruzyGqttikkLy0=
+github.com/makeworld-the-better-one/dither/v2 v2.4.0 h1:Az/dYXiTcwcRSe59Hzw4RI1rSnAZns+1msaCXetrMFE=
+github.com/makeworld-the-better-one/dither/v2 v2.4.0/go.mod h1:VBtN8DXO7SNtyGmLiGA7IsFeKrBkQPze1/iAeM95arc=
 github.com/mattn/go-isatty v0.0.20 h1:xfD0iDuEKnDkl03q4limB+vH+GxLEtL/jb4xVJSWWEY=
 github.com/mattn/go-isatty v0.0.20/go.mod h1:W+V8PltTTMOvKvAeJH7IuucS94S2C6jfK/D7dTCTo3Y=
 github.com/mattn/go-localereader v0.0.1 h1:ygSAOl7ZXTx4RdPYinUpg6W99U8jWvWi9Ye2JC/oIi4=
@@ -54,6 +61,8 @@ github.com/mattn/go-localereader v0.0.1/go.mod h1:8fBrzywKY7BI3czFoHkuzRoWE9C+Ei
 github.com/mattn/go-runewidth v0.0.12/go.mod h1:RAqKPSqVFrSLVXbA8x7dzmKdmGzieGRCM46jaSJTDAk=
 github.com/mattn/go-runewidth v0.0.16 h1:E5ScNMtiwvlvB5paMFdw9p4kSQzbXFikJ5SQO6TULQc=
 github.com/mattn/go-runewidth v0.0.16/go.mod h1:Jdepj2loyihRzMpdS35Xk/zdY8IAYHsh153qUoGf23w=
+github.com/mattn/go-sixel v0.0.5 h1:55w2FR5ncuhKhXrM5ly1eiqMQfZsnAHIpYNGZX03Cv8=
+github.com/mattn/go-sixel v0.0.5/go.mod h1:h2Sss+DiUEHy0pUqcIB6PFXo5Cy8sTQEFr3a9/5ZLNw=
 github.com/mitchellh/copystructure v1.2.0 h1:vpKXTN4ewci03Vljg/q9QvCGUDttBOGBIa15WveJJGw=
 github.com/mitchellh/copystructure v1.2.0/go.mod h1:qLl+cE2AmVv+CoeAwDPye/v+N2HKCj9FbZEVFJRxO9s=
 github.com/mitchellh/reflectwalk v1.0.2 h1:G2LzWKi524PWgd3mLHV8Y5k7s6XUvT0Gef6zxSIeXaQ=
@@ -66,6 +75,8 @@ github.com/muesli/reflow v0.3.0 h1:IFsN6K9NfGtjeggFP+68I4chLZV2yIKsXJFNZ+eWh6s=
 github.com/muesli/reflow v0.3.0/go.mod h1:pbwTDkVPibjO2kyvBQRBxTWEEGDGq0FlB1BIKtnHY/8=
 github.com/muesli/termenv v0.16.0 h1:S5AlUN9dENB57rsbnkPyfdGuWIlkmzJjbFf0Tf5FWUc=
 github.com/muesli/termenv v0.16.0/go.mod h1:ZRfOIKPFDYQoDFF4Olj7/QJbW60Ol/kL1pU3VfY/Cnk=
+github.com/nfnt/resize v0.0.0-20180221191011-83c6a9932646 h1:zYyBkD/k9seD2A7fsi6Oo2LfFZAehjjQMERAvZLEDnQ=
+github.com/nfnt/resize v0.0.0-20180221191011-83c6a9932646/go.mod h1:jpp1/29i3P1S/RLdc7JQKbRpFeM1dOBd8T9ki5s+AY8=
 github.com/pelletier/go-toml v1.9.5 h1:4yBQzkHv+7BHq2PQUZF3Mx0IYxG7LsP222s7Agd3ve8=
 github.com/pelletier/go-toml v1.9.5/go.mod h1:u1nR/EPcESfeI/szUZKdtJ0xRNbUoANCkoOuaOx1Y+c=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
@@ -74,8 +85,14 @@ github.com/rivo/uniseg v0.1.0/go.mod h1:J6wj4VEh+S6ZtnVlnTBMWIodfgj8LQOQFoIToxlJ
 github.com/rivo/uniseg v0.2.0/go.mod h1:J6wj4VEh+S6ZtnVlnTBMWIodfgj8LQOQFoIToxlJtxc=
 github.com/rivo/uniseg v0.4.7 h1:WUdvkW8uEhrYfLC4ZzdpI2ztxP1I582+49Oc5Mq64VQ=
 github.com/rivo/uniseg v0.4.7/go.mod h1:FN3SvrM+Zdj16jyLfmOkMNblXMcoc8DfTHruCPUcx88=
+github.com/rogpeppe/go-internal v1.14.1 h1:UQB4HGPB6osV0SQTLymcB4TgvyWu6ZyliaW0tI/otEQ=
+github.com/rogpeppe/go-internal v1.14.1/go.mod h1:MaRKkUm5W0goXpeCfT7UZI6fk/L7L7so1lCWt35ZSgc=
+github.com/soniakeys/quant v1.0.0 h1:N1um9ktjbkZVcywBVAAYpZYSHxEfJGzshHCxx/DaI0Y=
+github.com/soniakeys/quant v1.0.0/go.mod h1:HI1k023QuVbD4H8i9YdfZP2munIHU4QpjsImz6Y6zds=
 github.com/spf13/pflag v1.0.10 h1:4EBh2KAYBwaONj6b2Ye1GiHfwjqyROoF4RwYO+vPwFk=
 github.com/spf13/pflag v1.0.10/go.mod h1:McXfInJRrz4CZXVZOBLb0bTZqETkiAhM9Iw0y3An2Bg=
+github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
+github.com/stretchr/testify v1.6.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
 github.com/stretchr/testify v1.8.1 h1:w7B6lhMri9wdJUVmEZPGGhZzrYTPvgJArz7wNPgYKsk=
 github.com/stretchr/testify v1.8.1/go.mod h1:w2LPCIKwWwSfY2zedu0+kehJoqGctiVI29o6fzry7u4=
 github.com/xo/terminfo v0.0.0-20220910002029-abceb7e1c41e h1:JVG44RsyaB9T2KIHavMF/ppJZNG9ZpyihvCd0w101no=
@@ -89,6 +106,8 @@ golang.org/x/crypto v0.23.0/go.mod h1:CKFgDieR+mRhux2Lsu27y0fO304Db0wZe70UKqHu0v
 golang.org/x/crypto v0.31.0/go.mod h1:kDsLvtWBEx7MV9tJOj9bnXsPbxwJQ6csT/x4KIN4Ssk=
 golang.org/x/exp v0.0.0-20220909182711-5c715a9e8561 h1:MDc5xs78ZrZr3HMQugiXOAkSZtfTpbJLDr/lwfgO53E=
 golang.org/x/exp v0.0.0-20220909182711-5c715a9e8561/go.mod h1:cyybsKvd6eL0RnXn6p/Grxp8F5bW7iYuBgsNCOHpMYE=
+golang.org/x/image v0.25.0 h1:Y6uW6rH1y5y/LK1J8BPWZtr6yZ7hrsy6hFrXjgsc2fQ=
+golang.org/x/image v0.25.0/go.mod h1:tCAmOEGthTtkalusGp1g3xa2gke8J6c2N565dTyl9Rs=
 golang.org/x/mod v0.6.0-dev.0.20220419223038-86c51ed26bb4/go.mod h1:jJ57K6gSWd91VN4djpZkiMVwK6gcyfeH4XE8wZrZaV4=
 golang.org/x/mod v0.8.0/go.mod h1:iBbtSCu2XBx23ZKBPSOrRkjjQPZFPuis4dIYUhu/chs=
 golang.org/x/mod v0.12.0/go.mod h1:iBbtSCu2XBx23ZKBPSOrRkjjQPZFPuis4dIYUhu/chs=
@@ -104,6 +123,8 @@ golang.org/x/net v0.21.0/go.mod h1:bIjVDfnllIU7BJ2DNgfnXvpSvtn8VRwhlsaeUTyUS44=
 golang.org/x/net v0.25.0/go.mod h1:JkAGAh7GEvH74S6FOH42FLoXpXbE/aqXSrIQjXgsiwM=
 golang.org/x/net v0.33.0 h1:74SYHlV8BIgHIFC/LrYkOGIwL19eTYXQ5wc6TBuO36I=
 golang.org/x/net v0.33.0/go.mod h1:HXLR5J+9DxmrqMwG9qjGCxZ+zKXxBru04zlTvWlWuN4=
+golang.org/x/net v0.44.0 h1:evd8IRDyfNBMBTTY5XRF1vaZlD+EmWx6x8PkhR04H/I=
+golang.org/x/net v0.44.0/go.mod h1:ECOoLqd5U3Lhyeyo/QDCEVQ4sNgYsqvCZ722XogGieY=
 golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20220722155255-886fb9371eb4/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.1.0/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
@@ -154,6 +175,10 @@ golang.org/x/tools v0.1.12/go.mod h1:hNGJHUnrk76NpqgfD5Aqm5Crs+Hm0VOH/i9J2+nxYbc
 golang.org/x/tools v0.6.0/go.mod h1:Xwgl3UAJ/d3gWutnCtw505GrjyAbvKui8lOU390QaIU=
 golang.org/x/tools v0.13.0/go.mod h1:HvlwmtVNQAhOuCjW7xxvovg8wbNq7LwfXh/k7wXUl58=
 golang.org/x/tools v0.21.1-0.20240508182429-e35e4ccd0d2d/go.mod h1:aiJjzUbINMkxbQROHiO6hDPo2LHcIPhhQsa9DLh0yGk=
+golang.org/x/tools v0.37.0 h1:DVSRzp7FwePZW356yEAChSdNcQo6Nsp+fex1SUW09lE=
+golang.org/x/tools v0.37.0/go.mod h1:MBN5QPQtLMHVdvsbtarmTNukZDdgwdwlO5qGacAzF0w=
 golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
 gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
 gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

main.go

@@ -1,3 +1,19 @@
+/*
+Copyright © 2025 Thomas von Dein
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program. If not, see <http://www.gnu.org/licenses/>.
+*/
 package main
 
 import (

main_test.go

@@ -0,0 +1,38 @@
+/*
+Copyright © 2025 Thomas von Dein
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program. If not, see <http://www.gnu.org/licenses/>.
+*/
+
+package main
+
+import (
+	"testing"
+
+	"github.com/rogpeppe/go-internal/testscript"
+)
+
+// see https://bitfieldconsulting.com/golang/test-scripts
+
+func TestMain(m *testing.M) {
+	testscript.Main(m, map[string]func(){
+		"epuppy": main,
+	})
+}
+
+func TestEpuppy(t *testing.T) {
+	testscript.Run(t, testscript.Params{
+		Dir: "t",
+	})
+}

mkrel.sh

@@ -1,6 +1,6 @@
 #!/bin/bash
 
-# Copyright © 2024 Thomas von Dein
+# Copyright © 2025 Thomas von Dein
 
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by

pkg/epub/README.md

@@ -0,0 +1,21 @@
+# epub module
+
+This is a modified version of the [epub
+module](https://github.com/kapmahc/epub/). I fixed a couple of issues
+and I added code to retrieve the actual epub content, which the
+original module doesn't implement. Since the last update on that
+module was 9 years ago (as I write this), it doesn't make sense to
+send a PR. And it also makes no sense to me to publish it separately.
+
+
+# ORIGINAL README
+
+## epub
+A pure go implementation of epub file format.
+
+
+
+### Documents
+- <http://idpf.org/epub>
+- <http://www.cnblogs.com/Alex80/p/5127104.html>
+- <http://www.cnblogs.com/diligenceday/p/4999315.html>

pkg/epub/book.go

@@ -17,6 +17,9 @@ type Book struct {
 	Mimetype       string    `json:"-"`
 	Content        []Content
 	fd             *zip.ReadCloser
+	CoverImage     []byte
+	CoverFile      string
+	CoverMediaType string
 }
 
 // Open open resource file

pkg/epub/content.go

@@ -8,9 +8,10 @@ import (
 )
 
 var (
-	cleanentitles = regexp.MustCompile(`&.+;`)
+	cleanentitles = regexp.MustCompile(`&[a-z]+;`)
 	empty         = regexp.MustCompile(`(?s)^[\s ]*$`)
 	newlines      = regexp.MustCompile(`[\r\n]+`)
+	cleanmarkup   = regexp.MustCompile(`<[^<>]+>`)
 )
 
 // Content nav-point content
@@ -22,30 +23,45 @@ type Content struct {
 	XML   []byte
 }
 
-func (c *Content) String(content []byte) error {
 // parse XML, look for title and <p>.*</p> stuff
+func (c *Content) String(content []byte) error {
 	doc, err := xmlquery.Parse(
 		strings.NewReader(
 			cleanentitles.ReplaceAllString(string(content), " ")))
 	if err != nil {
-		panic(err)
+		return err
 	}
 
+	if c.Title == "" {
 		// extract the title
 		for _, item := range xmlquery.Find(doc, "//title") {
 			c.Title = strings.TrimSpace(item.InnerText())
 		}
+	}
 
 	// extract all  paragraphs, ignore any formatting  and re-fill the
-	// paragraph,  that is, we  replaces all newlines inside  with one
+	// paragraph,  that is, we  replace all newlines inside  with one
 	// space.
 	txt := strings.Builder{}
+	var have_p bool
 	for _, item := range xmlquery.Find(doc, "//p") {
 		if !empty.MatchString(item.InnerText()) {
+			have_p = true
 			txt.WriteString(newlines.ReplaceAllString(item.InnerText(), " ") + "\n\n")
 		}
 	}
 
+	if !have_p {
+		// try  <div></div>, which some  ebooks use, so get  all divs,
+		// remove markup and paragraphify the parts
+		for _, item := range xmlquery.Find(doc, "//div") {
+			if !empty.MatchString(item.InnerText()) {
+				cleaned := cleanmarkup.ReplaceAllString(item.InnerText(), "")
+				txt.WriteString(newlines.ReplaceAllString(cleaned, " ") + "\n\n")
+			}
+		}
+	}
+
 	c.Body = strings.TrimSpace(txt.String())
 	c.XML = content
 

pkg/epub/open.go

@@ -6,6 +6,8 @@ import (
 	"log"
 	"os"
 	"strings"
+
+	"github.com/alecthomas/repr"
 )
 
 // Open open a epub file
@@ -45,32 +47,64 @@ func Open(fn string, dumpxml bool) (*Book, error) {
 			if err != nil {
 				return &bk, err
 			}
+		}
 
-			break
+		if mf.ID == "cover-image" {
+			bk.CoverFile = mf.Href
+			bk.CoverMediaType = mf.MediaType
 		}
 	}
 
+	type section struct {
+		file, title string
+	}
+
+	sections := []section{}
+
+	if len(bk.Ncx.Points) > 0 {
+		for _, block := range bk.Ncx.Points {
+			sections = append(sections,
+				section{
+					file:  "OEBPS/" + block.Content.Src,
+					title: block.Text,
+				})
+		}
+	} else {
 		for _, file := range bk.Files() {
-		content, err := bk.readBytes(file)
+			sections = append(sections,
+				section{
+					file: file,
+				})
+		}
+	}
+
+	for _, section := range sections {
+		content, err := bk.readBytes(section.file)
 		if err != nil {
 			return &bk, err
 		}
 
-		ct := Content{Src: file}
+		if strings.Contains(section.file, bk.CoverFile) {
-		if strings.Contains(string(content), "<?xml") {
+			bk.CoverImage = content
+		}
+
+		ct := Content{Src: section.file, Title: section.title}
+
+		if strings.Contains(string(content), "<?xml") || strings.Contains(string(content), "<!DOCTYPE") {
 			if err := ct.String(content); err != nil {
 				return &bk, err
 			}
 		}
 
-		bk.Content = append(bk.Content, ct)
-
 		if dumpxml {
 			fmt.Println(string(ct.XML))
 		}
+
+		bk.Content = append(bk.Content, ct)
 	}
 
 	if dumpxml {
+		repr.Println(sections)
 		os.Exit(0)
 	}
 

t/basic.txtar

@@ -0,0 +1,7 @@
+# no args shall fail
+! exec epuppy
+
+# help
+exec epuppy -h
+stdout 'This is epuppy'
+