feat: add preview command (#203)

- Add a new `sesh preview` command
- Add configuration support for the preview command

README.md

@@ -111,7 +111,7 @@ In order to integrate with tmux, you can add a binding to your tmux config (`tmu
 
 ```sh
 bind-key "T" run-shell "sesh connect \"$(
-  sesh list --icons | fzf-tmux -p 55%,60% \
+  sesh list --icons | fzf-tmux -p 80%,70% \
     --no-sort --ansi --border-label ' sesh ' --prompt '⚡  ' \
     --header '  ^a all ^t tmux ^g configs ^x zoxide ^d tmux kill ^f find' \
     --bind 'tab:down,btab:up' \
@@ -121,6 +121,8 @@ bind-key "T" run-shell "sesh connect \"$(
     --bind 'ctrl-x:change-prompt(📁  )+reload(sesh list -z --icons)' \
     --bind 'ctrl-f:change-prompt(🔎  )+reload(fd -H -d 2 -t d -E .Trash . ~)' \
     --bind 'ctrl-d:execute(tmux kill-session -t {2..})+change-prompt(⚡  )+reload(sesh list --icons)' \
+    --preview-window 'right:55%' \
+    --preview 'sesh preview {}'
 )\""
 ```
 
@@ -222,9 +224,14 @@ mkdir -p ~/.config/sesh && touch ~/.config/sesh/sesh.toml
 
 The default session can be configured to run a command when connecting to a session. This is useful for running a dev server or starting a tmux plugin.
 
+Additionally, you can define a preview command that runs when previewing the session's directory. This can be handy for displaying files with tools like [eza](https://github.com/eza-community/eza) or [lsd](https://github.com/lsd-rs/lsd).
+
+Note: The `{}` will be automatically replaced with the session's path.
+
 ```toml
 [default_session]
 startup_command = "nvim -c ':Telescope find_files'"
+preview_command = "eza --all --git --icons --color=always {}"
 ```
 
 If you want to disable the default start command on a specific session, you can set `disable_startup_command = true`.
@@ -235,7 +242,9 @@ A startup command is a command that is run when a session is created. It is usef
 
 **Note:** If you use the `--command/-c` flag, then the startup script will not be run.
 
-I like to use a command that opens nvim on session startup:
+I like to use a command that opens nvim on session startup.
+
+You can also define a preview command to display the contents of a specific file using [bat](https://github.com/sharkdp/bat) or any another file previewer of your choice.
 
 ```toml
 [[session]]
@@ -247,6 +256,7 @@ startup_command = "ls"
 name = "tmux config"
 path = "~/c/dotfiles/.config/tmux"
 startup_command = "nvim tmux.conf"
+preview_command = "bat --color=always ~/c/dotfiles/.config/tmux/tmux.conf"
 ```
 
 ### Listing Configurations

lister/config.go

@@ -31,6 +31,7 @@ func listConfig(l *RealLister) (model.SeshSessions, error) {
 				Name:                  session.Name,
 				Path:                  path,
 				StartupCommand:        session.StartupCommand,
+				PreviewCommand:        session.PreviewCommand,
 				DisableStartupCommand: session.DisableStartCommand,
 				Tmuxinator:            session.Tmuxinator,
 			}

ls/ls.go

@@ -0,0 +1,37 @@
+package ls
+
+import (
+	"github.com/joshmedeski/sesh/model"
+	"github.com/joshmedeski/sesh/shell"
+)
+
+type Ls interface {
+	ListDirectory(name string) (string, error)
+}
+
+type RealLs struct {
+	config model.Config
+	shell  shell.Shell
+}
+
+func NewLs(config model.Config, shell shell.Shell) Ls {
+	return &RealLs{config, shell}
+}
+
+func (g *RealLs) ListDirectory(path string) (string, error) {
+	command := g.config.DefaultSessionConfig.PreviewCommand
+	if command == "" {
+		command = "ls {}"
+	}
+
+	cmdParts, err := g.shell.PrepareCmd(command, map[string]string{"{}": path})
+	if err != nil {
+		return "", err
+	}
+
+	cmdOutput, err := g.shell.Cmd(cmdParts[0], cmdParts[1:]...)
+	if err != nil {
+		return "", err
+	}
+	return cmdOutput, nil
+}

model/config.go

@@ -13,6 +13,7 @@ type (
 		StartupCommand string `toml:"startup_command"`
 		Tmuxp          string `toml:"tmuxp"`
 		Tmuxinator     string `toml:"tmuxinator"`
+		PreviewCommand string `toml:"preview_command"`
 	}
 
 	SessionConfig struct {

model/sesh_session.go

@@ -16,6 +16,7 @@ type (
 		Path string // The absolute directory path
 
 		StartupCommand        string  // The command to run when the session is started
+		PreviewCommand        string  // The command to run when the session is previewed
 		DisableStartupCommand bool    // Ignore the default startup command if present
 		Tmuxinator            string  // Name of the tmuxinator config
 		Attached              int     // Whether the session is currently attached

previewer/config.go

@@ -0,0 +1,41 @@
+package previewer
+
+import (
+	"github.com/joshmedeski/sesh/lister"
+	"github.com/joshmedeski/sesh/shell"
+)
+
+type ConfigPreviewStrategy struct {
+	lister lister.Lister
+	shell  shell.Shell
+}
+
+func NewConfigStrategy(lister lister.Lister, shell shell.Shell) *ConfigPreviewStrategy {
+	return &ConfigPreviewStrategy{lister: lister, shell: shell}
+}
+
+func (s *ConfigPreviewStrategy) Execute(name string) (string, error) {
+	session, configExists := s.lister.FindConfigSession(name)
+	if !configExists {
+		return "", nil
+	}
+
+	if session.PreviewCommand == "" {
+		return "", nil
+	}
+
+	replacements := map[string]string{
+		"{}": session.Path,
+	}
+	cmdParts, err := s.shell.PrepareCmd(session.PreviewCommand, replacements)
+	if err != nil {
+		return "", err
+	}
+
+	cmdOutput, err := s.shell.Cmd(cmdParts[0], cmdParts[1:]...)
+	if err != nil {
+		return "", err
+	}
+
+	return cmdOutput, nil
+}