initial

1 files changed, 70 insertions, 0 deletions

diff --git a/internal/log/log.go b/internal/log/log.go
new file mode 100644
index 0000000..68635c3
--- /dev/null
+++ b/internal/log/log.go
@@ -0,0 +1,70 @@
+// Package log centralizes all user-facing output behind package-level
+// functions backed by a private global logger. Normal output (actions, summary)
+// goes to stdout; warnings and errors go to stderr. For a single-process CLI a
+// global sink avoids threading a logger through every call site.
+package log
+
+import (
+	"fmt"
+	"io"
+	"os"
+)
+
+// global is the process-wide logger. It defaults to the real stdout/stderr so the
+// package is usable without explicit setup (e.g. in tests).
+var global = &logger{stdout: os.Stdout, stderr: os.Stderr}
+
+type logger struct {
+	stdout  io.Writer
+	stderr  io.Writer
+	verbose bool
+	quiet   bool
+}
+
+// Init configures the global logger's destinations. Call once at startup.
+func Init(out, err io.Writer) {
+	global.stdout = out
+	global.stderr = err
+}
+
+// SetVerbose toggles whether commands include extra detail in their output.
+func SetVerbose(v bool) { global.verbose = v }
+
+// SetQuiet toggles whether normal output is suppressed. Quiet wins over verbose
+// (see DESIGN §13): the two are points on one scale, quiet > verbose > default.
+func SetQuiet(q bool) { global.quiet = q }
+
+// Verbose reports whether verbose output is enabled. It folds the quiet override
+// in, so callers never re-check quiet: quiet suppresses verbose detail.
+func Verbose() bool { return global.verbose && !global.quiet }
+
+// Print writes a normal output line to stdout. It is suppressed under quiet.
+func Print(format string, args ...any) {
+	if !global.quiet {
+		fmt.Fprintf(global.stdout, format+"\n", args...)
+	}
+}
+
+// PrintVerbose writes an extra-detail line to stdout, emitted only when verbose
+// output is enabled (and not suppressed by quiet, per Verbose()).
+func PrintVerbose(format string, args ...any) {
+	if Verbose() {
+		fmt.Fprintf(global.stdout, format+"\n", args...)
+	}
+}
+
+// PrintImportant writes a line to stdout that survives quiet (e.g. the final
+// summary).
+func PrintImportant(format string, args ...any) {
+	fmt.Fprintf(global.stdout, format+"\n", args...)
+}
+
+// Warn prints a warning to stderr. Warnings are never suppressed.
+func Warn(format string, args ...any) {
+	fmt.Fprintf(global.stderr, "Warning: "+format+"\n", args...)
+}
+
+// Error prints an error to stderr. Errors are never suppressed.
+func Error(format string, args ...any) {
+	fmt.Fprintf(global.stderr, "Error: "+format+"\n", args...)
+}