use colored::*;
use mp3rgain::replaygain::{self, REPLAYGAIN_REFERENCE_DB};
use mp3rgain::GAIN_STEP_DB;
pub const VERSION: &str = env!("CARGO_PKG_VERSION");
pub fn print_version() {
println!("mp3rgain version {}", VERSION);
println!("A modern mp3gain replacement written in Rust");
println!();
println!("Each gain step = {} dB", GAIN_STEP_DB);
}
pub fn print_usage() {
println!("{} version {}", "mp3rgain".green().bold(), VERSION);
println!("Lossless MP3 volume adjustment - a modern mp3gain replacement");
println!();
println!("{}", "USAGE:".cyan().bold());
println!(" mp3rgain [OPTIONS] <FILES>...");
println!();
println!("{}", "OPTIONS:".cyan().bold());
println!(
" -g <i> Apply gain of i steps (each step = {} dB)",
GAIN_STEP_DB
);
println!(" -d <n> Apply gain of n dB (rounded to nearest step)");
println!(" -l <c> <g> Apply gain to left (0) or right (1) channel only");
println!(" -m <i> Modify suggested gain by integer i");
println!(" -r Apply Track gain (ReplayGain analysis)");
println!(" -a Apply Album gain (ReplayGain analysis)");
println!(" -e Skip album analysis (even with multiple files)");
println!(" -i <n> Specify which audio track to process (default: 0)");
println!(" -u Undo gain changes (restore from APEv2 tag)");
println!(" -x Only find max amplitude of file");
println!(" -s <mode> Stored tag handling:");
println!(" c = check/show stored tag info");
println!(" d = delete stored tag info");
println!(" s = skip (ignore) stored tag info");
println!(" r = force recalculation");
println!(" i = use ID3v2 tags (not fully supported)");
println!(" a = use APEv2 tags (default)");
println!(" -p Preserve original file timestamp");
println!(" -c Ignore clipping warnings");
println!(" -k Prevent clipping (automatically limit gain)");
println!(" -w Wrap gain values (instead of clamping)");
println!(" -t Use temp file for writing (safer, required for some ops)");
println!(" -f Assume MPEG 2 Layer III (compatibility, no effect)");
println!(" -q Quiet mode (less output)");
println!(" -R Process directories recursively");
println!(" -n Dry-run mode (show what would be done)");
println!(" --dry-run Same as -n");
println!(" --skip-errors Skip files that fail to analyze instead of");
println!(" aborting (useful for `-a` on large libraries)");
println!(" -j <n> Worker threads for analysis (default: auto, 0=auto, 1=serial)");
println!(" --threads <n> Same as -j (also honors MP3RGAIN_THREADS env var)");
println!(" -o <fmt> Output format: 'text' (default), 'json', or 'tsv'");
println!(" -v Show version");
println!(" -h Show this help");
println!();
println!("{}", "EXAMPLES:".cyan().bold());
println!(" mp3rgain song.mp3 Show file info");
println!(" mp3rgain -g 2 song.mp3 Apply +2 steps (+3.0 dB)");
println!(" mp3rgain -g -3 song.mp3 Apply -3 steps (-4.5 dB)");
println!(" mp3rgain -d 4.5 song.mp3 Apply +4.5 dB (rounds to +3 steps)");
println!(" mp3rgain -r song.mp3 Analyze and apply track gain");
println!(" mp3rgain -a *.mp3 Analyze and apply album gain");
println!(" mp3rgain -r -m 2 *.mp3 Apply track gain + 2 steps");
println!(" mp3rgain -e *.mp3 Track gain only (skip album calc)");
println!(" mp3rgain -u song.mp3 Undo previous gain changes");
println!(" mp3rgain -x song.mp3 Show max amplitude only");
println!(" mp3rgain -s c *.mp3 Check stored tag info");
println!(" mp3rgain -s d *.mp3 Delete stored tag info");
println!(" mp3rgain -g 2 -p song.mp3 Apply gain, preserve timestamp");
println!(" mp3rgain -k -g 5 song.mp3 Apply gain with clipping prevention");
println!(" mp3rgain -w -g 10 song.mp3 Apply gain with wrapping");
println!(" mp3rgain -t -g 2 song.mp3 Apply gain using temp file");
println!(" mp3rgain -R /path/to/music Process directory recursively");
println!(" mp3rgain -Rpa --skip-errors /music Album-scan a library, skipping");
println!(" files that fail to decode");
println!(" mp3rgain -n -g 2 *.mp3 Dry-run (preview changes)");
println!(" mp3rgain -o json song.mp3 Output in JSON format");
println!(" mp3rgain -o tsv *.mp3 Output in tab-separated format");
println!(" mp3rgain -l 0 3 song.mp3 Apply +3 steps to left channel");
println!(" mp3rgain -l 1 -2 song.mp3 Apply -2 steps to right channel");
println!();
println!("{}", "NOTES:".cyan().bold());
println!(
" - Each gain step = {} dB (fixed by MP3 specification)",
GAIN_STEP_DB
);
println!(" - Changes are lossless and reversible");
println!(" - Gain changes are stored in APEv2 tags for undo support");
println!(" - Progress bar shown automatically for 5+ files");
if replaygain::is_available() {
println!(
" - ReplayGain analysis is {} (target: {} dB)",
"enabled".green(),
REPLAYGAIN_REFERENCE_DB
);
} else {
println!();
println!("{}", "REPLAYGAIN:".yellow().bold());
println!(" -r and -a options require the 'replaygain' feature:");
println!(" cargo install mp3rgain --features replaygain");
}
}