gnoma/internal/safety/banner.go

package safety

import (
	"fmt"
	"path/filepath"
	"strings"
)

// SessionInfo carries the bits of session state the banner shows.
// Caller passes whatever is known at launch time; empty fields are
// omitted from the rendered banner.
type SessionInfo struct {
	Version     string // e.g. "0.2.1"
	GitBranch   string // empty if not in a git repo
	GitDirty    bool   // true if working tree has uncommitted changes
	ProjectType string // free-form, e.g. "Go module (somegit.dev/...)"
	Provider    string // e.g. "ollama"
	Model       string // e.g. "qwen3-coder:30b"
	Permission  string // e.g. "auto", "accept_edits"
	Incognito   bool
	Prefer      string // "auto" / "local" / "cloud"
	Tenant      string // optional, e.g. Kubernetes context name
}

// RenderContextBanner returns the always-shown banner with cwd, git,
// project, model, modes, and sensitive-file inventory. Result includes
// a trailing newline. Deterministic — safe for golden-string testing.
func RenderContextBanner(c Classification, info SessionInfo, sensitive []Match) string {
	var sb strings.Builder

	header := "gnoma"
	if info.Version != "" {
		header += " " + info.Version
	}
	header += " — ready"
	sb.WriteString(header + "\n")

	// Field labels are padded to 9 characters so the ":" separators
	// align in monospace output. "sensitive" sets the width; everything
	// else pads to match.
	writeField(&sb, "cwd      ", c.Path)
	if info.GitBranch != "" {
		state := "clean"
		if info.GitDirty {
			state = "dirty"
		}
		writeField(&sb, "git      ", fmt.Sprintf("%s (%s)", info.GitBranch, state))
	}
	if info.ProjectType != "" {
		writeField(&sb, "project  ", info.ProjectType)
	}
	if info.Provider != "" || info.Model != "" {
		writeField(&sb, "provider ", strings.TrimSpace(info.Provider+" / "+info.Model))
	}
	modes := renderModes(info)
	if modes != "" {
		writeField(&sb, "mode     ", modes)
	}
	if info.Tenant != "" {
		writeField(&sb, "tenant   ", info.Tenant)
	}

	if len(sensitive) > 0 {
		summary := fmt.Sprintf("%d match", len(sensitive))
		if len(sensitive) != 1 {
			summary = fmt.Sprintf("%d matches", len(sensitive))
		}
		names := make([]string, 0, len(sensitive))
		shown := len(sensitive)
		if shown > 3 {
			shown = 3
		}
		for i := 0; i < shown; i++ {
			names = append(names, filepath.Base(sensitive[i].Path))
		}
		if len(sensitive) > shown {
			names = append(names, fmt.Sprintf("+%d more", len(sensitive)-shown))
		}
		writeField(&sb, "sensitive", fmt.Sprintf("%s: %s", summary, strings.Join(names, ", ")))
	} else {
		writeField(&sb, "sensitive", "0 matches in cwd")
	}

	sb.WriteString("---\n")
	return sb.String()
}

// RenderWarnPrefix returns the banner text shown above the context
// banner when the cwd is TierWarn. The caller is responsible for
// reading a confirmation keystroke after printing this. Empty when
// the tier isn't TierWarn.
func RenderWarnPrefix(c Classification) string {
	if c.Tier != TierWarn {
		return ""
	}
	return fmt.Sprintf(
		"WARNING: cwd is %s (%s).\n"+
			"  Any file the model reads / writes / executes is in your\n"+
			"  personal directory — including .ssh/, .aws/, shell history,\n"+
			"  browser profiles.\n"+
			"  Continue? [y/N] ",
		c.Path, c.Reason,
	)
}

// RenderRefuse returns the banner text shown when the cwd is
// TierRefuse. Caller prints this and exits non-zero.
func RenderRefuse(c Classification) string {
	if c.Tier != TierRefuse {
		return ""
	}
	return fmt.Sprintf(
		"ERROR: gnoma will not start in %s.\n"+
			"  This directory (%s) contains system-critical files that\n"+
			"  should never be edited by a model. To override (you almost\n"+
			"  certainly should not), pass --dangerously-allow-anywhere.\n",
		c.Path, c.Reason,
	)
}

func writeField(sb *strings.Builder, label, value string) {
	if value == "" {
		return
	}
	sb.WriteString(label + " : " + value + "\n")
}

func renderModes(info SessionInfo) string {
	var parts []string
	if info.Permission != "" {
		parts = append(parts, "permission="+info.Permission)
	}
	if info.Incognito {
		parts = append(parts, "incognito=on")
	} else if info.Permission != "" || info.Prefer != "" {
		// Show incognito=off only when other modes are also rendered;
		// keeps a bare banner from being noisier than necessary.
		parts = append(parts, "incognito=off")
	}
	if info.Prefer != "" && info.Prefer != "auto" {
		parts = append(parts, "prefer="+info.Prefer)
	}
	return strings.Join(parts, " ")
}