From 4b62ae8b27524dcbb1f9a5dcca16b1b7161c3b4b Mon Sep 17 00:00:00 2001
From: Anton Novojilov <andy@essentialkaos.com>
Date: Mon, 2 Oct 2023 23:49:49 +0300
Subject: [PATCH] Add -X/--extra option to print the last lines of command
 output if action failed

---
 action/auxi.go           | 32 ++++++++++++++++++++++++++++++--
 cli/cli.go               |  6 ++++++
 cli/executor/executor.go | 11 +++++++++++
 3 files changed, 47 insertions(+), 2 deletions(-)

diff --git a/action/auxi.go b/action/auxi.go
index 3b083c9c..6000d3e0 100644
--- a/action/auxi.go
+++ b/action/auxi.go
@@ -82,6 +82,32 @@ func (c *OutputContainer) String() string {
 	return c.buf.String()
 }
 
+// Tail return the last lines of output
+func (c *OutputContainer) Tail(lines int) string {
+	if c.IsEmpty() {
+		return ""
+	}
+
+	if c.buf.Len() < lines+2 {
+		return c.String()
+	}
+
+	data := c.buf.Bytes()
+	line := 0
+
+	for i := len(data) - 2; i >= 0; i-- {
+		if data[i] == '\n' {
+			line++
+		}
+
+		if line == lines {
+			return strings.TrimRight(string(data[i+1:]), " \n\r")
+		}
+	}
+
+	return strings.TrimRight(string(data), " \n\r")
+}
+
 // IsEmpty returns true if container is empty
 func (c *OutputContainer) IsEmpty() bool {
 	return c == nil || c.buf == nil || c.buf.Len() == 0
@@ -89,9 +115,11 @@ func (c *OutputContainer) IsEmpty() bool {
 
 // Purge clears data
 func (c *OutputContainer) Purge() {
-	if c == nil || c.buf != nil {
-		c.buf.Reset()
+	if c == nil || c.buf == nil {
+		return
 	}
+
+	c.buf.Reset()
 }
 
 // ////////////////////////////////////////////////////////////////////////////////// //
diff --git a/cli/cli.go b/cli/cli.go
index d18afd4e..a60a72f3 100644
--- a/cli/cli.go
+++ b/cli/cli.go
@@ -15,6 +15,7 @@ import (
 
 	"github.com/essentialkaos/ek/v12/fmtc"
 	"github.com/essentialkaos/ek/v12/fmtutil"
+	"github.com/essentialkaos/ek/v12/fmtutil/panel"
 	"github.com/essentialkaos/ek/v12/fmtutil/table"
 	"github.com/essentialkaos/ek/v12/fsutil"
 	"github.com/essentialkaos/ek/v12/options"
@@ -52,6 +53,7 @@ const (
 	OPT_LIST_PACKAGES_FLAT = "L1:list-packages-flat"
 	OPT_VARIABLES          = "V:variables"
 	OPT_BARCODE            = "B:barcode"
+	OPT_EXTRA              = "X:extra"
 	OPT_TIME               = "T:time"
 	OPT_FORMAT             = "f:format"
 	OPT_DIR                = "d:dir"
@@ -78,6 +80,7 @@ var optMap = options.Map{
 	OPT_LIST_PACKAGES_FLAT: {Type: options.BOOL},
 	OPT_VARIABLES:          {Type: options.BOOL},
 	OPT_BARCODE:            {Type: options.BOOL},
+	OPT_EXTRA:              {Type: options.BOOL},
 	OPT_TIME:               {Type: options.BOOL},
 	OPT_FORMAT:             {},
 	OPT_DIR:                {},
@@ -189,6 +192,7 @@ func configureUI() {
 	}
 
 	fmtutil.SeparatorSymbol = "–"
+	panel.Indent = 5
 }
 
 // configureSubsystems configures bibop subsystems
@@ -277,6 +281,7 @@ func process(file string) {
 	}
 
 	cfg := &executor.Config{
+		Debug:          options.GetB(OPT_EXTRA),
 		Quiet:          options.GetB(OPT_QUIET),
 		DisableCleanup: options.GetB(OPT_NO_CLEANUP),
 		ErrsDir:        errDir,
@@ -456,6 +461,7 @@ func genUsage() *usage.Info {
 	info.AppNameColorTag = "{*}" + colorTagApp
 
 	info.AddOption(OPT_DRY_RUN, "Parse and validate recipe")
+	info.AddOption(OPT_EXTRA, "Print the last lines from command output if action was failed")
 	info.AddOption(OPT_LIST_PACKAGES, "List required packages")
 	info.AddOption(OPT_LIST_PACKAGES_FLAT, "List required packages in one line {s-}(useful for scripts){!}")
 	info.AddOption(OPT_VARIABLES, "List recipe variables")
diff --git a/cli/executor/executor.go b/cli/executor/executor.go
index c32f53c3..69d341a7 100644
--- a/cli/executor/executor.go
+++ b/cli/executor/executor.go
@@ -17,6 +17,8 @@ import (
 	"time"
 
 	"github.com/essentialkaos/ek/v12/errutil"
+	"github.com/essentialkaos/ek/v12/fmtc"
+	"github.com/essentialkaos/ek/v12/fmtutil/panel"
 	"github.com/essentialkaos/ek/v12/fsutil"
 	"github.com/essentialkaos/ek/v12/log"
 	"github.com/essentialkaos/ek/v12/req"
@@ -54,6 +56,7 @@ type Executor struct {
 type Config struct {
 	ErrsDir        string
 	Quiet          bool
+	Debug          bool
 	DisableCleanup bool
 }
 
@@ -287,6 +290,14 @@ func runCommand(e *Executor, rr render.Renderer, c *recipe.Command) bool {
 		}
 
 		if err != nil {
+			if !e.config.Quiet && e.config.Debug && !cmdEnv.output.IsEmpty() {
+				fmtc.NewLine()
+				panel.Panel(
+					"☴ OUTPUT", "{y}", "The last 10 lines from command output",
+					cmdEnv.output.Tail(10), panel.BOTTOM_LINE,
+				)
+			}
+
 			logError(e, c, action, cmdEnv, err)
 			return false
 		}