gui: syntax colours, a file preview, and a settings window

1 files changed, 62 insertions, 0 deletions

diff --git a/gui/internal/model/prefs.go b/gui/internal/model/prefs.go
new file mode 100644
index 0000000..ce9ee42
--- /dev/null
+++ b/gui/internal/model/prefs.go
@@ -0,0 +1,62 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+package model
+
+import (
+	"encoding/json"
+	"os"
+	"path/filepath"
+
+	"krino/internal/xdg"
+)
+
+// Prefs is how the window behaves - nothing about what krino does to
+// files, which belongs in the configuration. It lives beside krino.conf as
+// gui.json, a file krino itself never reads (his request, 2026-09-16).
+type Prefs struct {
+	// FontSize is the editor's font in points; 0 keeps the theme's.
+	FontSize int `json:"font_size"`
+	// Colours paints the configuration in the Text tab.
+	Colours bool `json:"colours"`
+	// Preview shows the file behind the selected row in the Plan tab.
+	Preview bool `json:"preview"`
+	// SelectAll starts a plan's rows checked, as the terminal review does.
+	SelectAll bool `json:"select_all"`
+}
+
+// DefaultPrefs is what a window does before anything is chosen.
+func DefaultPrefs() Prefs {
+	return Prefs{FontSize: 0, Colours: true, Preview: true, SelectAll: true}
+}
+
+// PrefsFile is where they are kept.
+func PrefsFile() string {
+	return filepath.Join(xdg.ConfigHome(), "krino", "gui.json")
+}
+
+// LoadPrefs reads them. A missing or unreadable file is not an error: the
+// window opens with the defaults, as it does the first time.
+func LoadPrefs() Prefs {
+	p := DefaultPrefs()
+	data, err := os.ReadFile(PrefsFile())
+	if err != nil {
+		return p
+	}
+	if err := json.Unmarshal(data, &p); err != nil {
+		return DefaultPrefs()
+	}
+	return p
+}
+
+// Save writes them, creating the directory if it is not there yet.
+func (p Prefs) Save() error {
+	data, err := json.MarshalIndent(p, "", "  ")
+	if err != nil {
+		return err
+	}
+	file := PrefsFile()
+	if err := os.MkdirAll(filepath.Dir(file), 0o755); err != nil {
+		return err
+	}
+	return os.WriteFile(file, append(data, '\n'), 0o644)
+}