package main

import (
	"bytes"
	"strings"
	"testing"
)

func TestParseArgsHelpStopsBeforeValidation(t *testing.T) {
	var stdout, stderr bytes.Buffer

	result, err := parseArgs([]string{"--help"}, &stdout, &stderr)
	if err != nil {
		t.Fatalf("parseArgs: %v", err)
	}
	if result.shouldRun {
		t.Fatal("shouldRun = true, want false")
	}
	if !result.args.showHelp {
		t.Fatal("showHelp = false, want true")
	}
	if !strings.Contains(stdout.String(), "Usage: mxl-gen") {
		t.Fatalf("help output does not contain usage: %q", stdout.String())
	}
	if stderr.Len() != 0 {
		t.Fatalf("stderr = %q, want empty", stderr.String())
	}
}

func TestParseArgsListPatternsStopsBeforeValidation(t *testing.T) {
	var stdout, stderr bytes.Buffer

	result, err := parseArgs([]string{"--list-patterns"}, &stdout, &stderr)
	if err != nil {
		t.Fatalf("parseArgs: %v", err)
	}
	if result.shouldRun {
		t.Fatal("shouldRun = true, want false")
	}
	if !result.args.listPatterns {
		t.Fatal("listPatterns = false, want true")
	}
	if !strings.Contains(stdout.String(), "ebu75") {
		t.Fatalf("pattern output does not contain ebu75: %q", stdout.String())
	}
	if stderr.Len() != 0 {
		t.Fatalf("stderr = %q, want empty", stderr.String())
	}
}

func TestParseArgsRejectsUnexpectedPositionalArguments(t *testing.T) {
	var stdout, stderr bytes.Buffer

	result, err := parseArgs([]string{"unexpected"}, &stdout, &stderr)
	if err == nil {
		t.Fatal("parseArgs returned nil error")
	}
	if result.shouldRun {
		t.Fatal("shouldRun = true, want false")
	}
	if !strings.Contains(err.Error(), "unexpected positional arguments") {
		t.Fatalf("error = %q", err)
	}
}

func TestParseArgsRejectsUnknownFlag(t *testing.T) {
	var stdout, stderr bytes.Buffer

	result, err := parseArgs([]string{"--not-a-flag"}, &stdout, &stderr)
	if err == nil {
		t.Fatal("parseArgs returned nil error")
	}
	if result.shouldRun {
		t.Fatal("shouldRun = true, want false")
	}
}

func TestValidateAudioArgsSkipsDisabledAudio(t *testing.T) {
	args := appArgs{
		audioChannels:     0,
		audioSamplingFreq: "unsupported",
		audioUUID:         "not-a-uuid",
	}

	if err := validateAudioArgs(&args); err != nil {
		t.Fatalf("validateAudioArgs: %v", err)
	}
	if args.audioUUID != "not-a-uuid" {
		t.Fatalf("audio UUID changed while audio is disabled: %q", args.audioUUID)
	}
}

func TestListPatternsIsSorted(t *testing.T) {
	var output bytes.Buffer
	listPatterns(&output)

	text := output.String()
	if strings.Index(text, "ebu100") > strings.Index(text, "ebu75") {
		t.Fatalf("patterns are not sorted: %q", text)
	}
}