diff --git a/internal/verbose/verbose.go b/internal/verbose/verbose.go new file mode 100644 index 0000000..6fddc27 --- /dev/null +++ b/internal/verbose/verbose.go @@ -0,0 +1,68 @@ +// Package verbose provides a process-wide verbosity level and a pluggable +// log sink so verbose output integrates with the downloader's progress bars. +// +// Level meaning: +// +// 0 (Off) - no extra output +// 1 (V) - log per-track CDN URLs from the downloader +// 2 (VV) - additionally log every outbound HTTP request via the +// netutil-wrapped transport (covers all provider API calls +// and downloads) +package verbose + +import ( + "fmt" + "os" + "sync/atomic" +) + +const ( + Off byte = 0 + V byte = 1 + VV byte = 2 +) + +var ( + level atomic.Uint32 + sink atomic.Pointer[func(string)] +) + +// SetLevel clamps and stores the verbosity level. Pass 0 to disable. +func SetLevel(l int) { + if l < 0 { + l = 0 + } + if l > int(VV) { + l = int(VV) + } + level.Store(uint32(l)) +} + +func Level() byte { return byte(level.Load()) } + +func Enabled(l byte) bool { return Level() >= l } + +// SetSink installs a writer for verbose output. Use this to route logs +// through the downloader so they don't tear progress bars. Pass nil to +// fall back to stderr. +func SetSink(fn func(string)) { + if fn == nil { + sink.Store(nil) + return + } + sink.Store(&fn) +} + +// Printf emits a line at the given level if verbosity is enabled. The +// caller is responsible for including a trailing newline. +func Printf(l byte, format string, args ...any) { + if !Enabled(l) { + return + } + msg := fmt.Sprintf(format, args...) + if p := sink.Load(); p != nil { + (*p)(msg) + return + } + _, _ = fmt.Fprint(os.Stderr, msg) +}