package auth

import (
	"strings"
	"testing"
)

func TestGenerateToken(t *testing.T) {
	tok := GenerateToken()
	if len(tok) != 32 {
		t.Errorf("expected 32-char token, got %d chars: %s", len(tok), tok)
	}
	// Must be hex.
	for _, c := range tok {
		if !((c >= '0' && c <= '9') || (c >= 'a' && c <= 'f')) {
			t.Errorf("token contains non-hex char: %c", c)
		}
	}
}

func TestGenerateToken_Uniqueness(t *testing.T) {
	// Two tokens should never collide.
	t1 := GenerateToken()
	t2 := GenerateToken()
	if t1 == t2 {
		t.Error("two generated tokens are identical")
	}
}

func TestGenerateUUID(t *testing.T) {
	uuid := GenerateUUID()
	// Format: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx (36 chars).
	if len(uuid) != 36 {
		t.Errorf("expected 36-char UUID, got %d: %s", len(uuid), uuid)
	}
	// Check dashes at correct positions.
	for _, pos := range []int{8, 13, 18, 23} {
		if uuid[pos] != '-' {
			t.Errorf("expected dash at position %d, got %c", pos, uuid[pos])
		}
	}
	// Version 4: char at position 14 should be '4'.
	if uuid[14] != '4' {
		t.Errorf("expected version 4 at position 14, got %c", uuid[14])
	}
}

func TestGenerateUUID_Uniqueness(t *testing.T) {
	u1 := GenerateUUID()
	u2 := GenerateUUID()
	if u1 == u2 {
		t.Error("two generated UUIDs are identical")
	}
}

func TestHashPassword(t *testing.T) {
	hash, err := HashPassword("testpassword")
	if err != nil {
		t.Fatalf("HashPassword failed: %v", err)
	}
	if !strings.HasPrefix(hash, "$2a$") {
		t.Errorf("expected bcrypt hash starting with $2a$, got: %s", hash[:4])
	}
}

func TestVerifyPassword(t *testing.T) {
	hash, err := HashPassword("minecraft123")
	if err != nil {
		t.Fatalf("HashPassword failed: %v", err)
	}

	if !VerifyPassword("minecraft123", hash) {
		t.Error("VerifyPassword returned false for correct password")
	}
	if VerifyPassword("wrongpassword", hash) {
		t.Error("VerifyPassword returned true for wrong password")
	}
}

func TestIsBcryptHash(t *testing.T) {
	tests := []struct {
		hash string
		want bool
	}{
		{"$2a$10$abcdefghijklmnopqrstuuxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx", true},
		{"$2b$10$abcdefghijklmnopqrstuuxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx", true},
		{"$2y$10$abcdefghijklmnopqrstuuxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx", true},
		{"5e884898da28047151d0e56f8dc6292773603d0d6aabbdd62a11ef721d1542d8", false},
		{"", false},
		{"plaintext", false},
	}
	for _, tt := range tests {
		got := IsBcryptHash(tt.hash)
		if got != tt.want {
			t.Errorf("IsBcryptHash(%q) = %v, want %v", tt.hash, got, tt.want)
		}
	}
}

func TestExtractBearer(t *testing.T) {
	tests := []struct {
		header string
		want   string
	}{
		{"Bearer abc123", "abc123"},
		{"Bearer ", ""},
		{"abc123", ""},
		{"", ""},
		{"Basic abc123", ""},
	}
	for _, tt := range tests {
		got := ExtractBearer(tt.header)
		if got != tt.want {
			t.Errorf("ExtractBearer(%q) = %q, want %q", tt.header, got, tt.want)
		}
	}
}