package validator

import (
	"strings"
	"testing"
)

func TestValidateDomain(t *testing.T) {
	v := DefaultDomainValidator()

	tests := []struct {
		name    string
		input   string
		wantErr bool
	}{
		{"simple domain", "example.com", false},
		{"subdomain", "api.example.com", false},
		{"deep subdomain", "a.b.c.example.com", false},
		{"hyphen in middle", "my-site.example.com", false},
		{"co.uk tld", "example.co.uk", false},
		{"uppercase", "EXAMPLE.COM", false},

		{"empty", "", true},
		{"whitespace only", "   ", true},
		{"with scheme http", "http://example.com", true},
		{"with scheme https", "https://example.com", true},
		{"path traversal", "example.com/../etc", true},
		{"shell metachar ;", "example.com;whoami", true},
		{"shell metachar |", "example.com|whoami", true},
		{"shell metachar &", "example.com&ls", true},
		{"backtick", "example.com`id`", true},
		{"dollar", "example.com$USER", true},
		{"newline", "example.com\nmalicious", true},
		{"null byte", "example.com\x00.evil", true},
		{"leading hyphen label", "-example.com", true},
		{"trailing hyphen label", "example-.com", true},
		{"double dot", "example..com", true},
		{"label too long", strings.Repeat("a", 64) + ".com", true},
		{"domain too long", strings.Repeat("a.", 130) + "com", true},
		{"numeric tld", "example.123", true},
		{"single label", "localhost", true},
		{"angle brackets", "<script>.com", true},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			err := v.ValidateDomain(tt.input)
			if (err != nil) != tt.wantErr {
				t.Errorf("ValidateDomain(%q) error = %v, wantErr %v", tt.input, err, tt.wantErr)
			}
		})
	}
}

func TestSanitizeDomain(t *testing.T) {
	tests := []struct {
		input string
		want  string
	}{
		{"example.com", "example.com"},
		{"  example.com  ", "example.com"},
		{"EXAMPLE.COM", "example.com"},
		{"http://example.com", "example.com"},
		{"https://example.com", "example.com"},
		{"https://example.com/", "example.com"},
		{"HTTPS://Example.com/", "example.com"},
	}

	for _, tt := range tests {
		t.Run(tt.input, func(t *testing.T) {
			got := SanitizeDomain(tt.input)
			if got != tt.want {
				t.Errorf("SanitizeDomain(%q) = %q, want %q", tt.input, got, tt.want)
			}
		})
	}
}

func TestValidateIP(t *testing.T) {
	tests := []struct {
		name    string
		input   string
		wantErr bool
	}{
		{"ipv4", "8.8.8.8", false},
		{"ipv4 with whitespace", "  1.1.1.1  ", false},
		{"ipv6", "::1", false},
		{"ipv6 full", "2001:db8::1", false},
		{"empty", "", true},
		{"invalid format", "not-an-ip", true},
		{"out of range", "999.999.999.999", true},
		{"with port (invalid for ParseIP)", "8.8.8.8:53", true},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			err := ValidateIP(tt.input)
			if (err != nil) != tt.wantErr {
				t.Errorf("ValidateIP(%q) error = %v, wantErr %v", tt.input, err, tt.wantErr)
			}
		})
	}
}

func TestValidatePort(t *testing.T) {
	tests := []struct {
		port    int
		wantErr bool
	}{
		{1, false},
		{80, false},
		{443, false},
		{65535, false},
		{0, true},
		{-1, true},
		{65536, true},
		{100000, true},
	}

	for _, tt := range tests {
		err := ValidatePort(tt.port)
		if (err != nil) != tt.wantErr {
			t.Errorf("ValidatePort(%d) error = %v, wantErr %v", tt.port, err, tt.wantErr)
		}
	}
}

func TestValidateWordlistPath(t *testing.T) {
	tests := []struct {
		name    string
		input   string
		wantErr bool
	}{
		{"empty allowed", "", false},
		{"relative path", "wordlists/subdomains.txt", false},
		{"absolute path", "/tmp/wordlist.txt", false},
		{"path traversal", "../../../etc/passwd", true},
		{"path traversal mid", "safe/../../../etc/passwd", true},
		{"null byte", "wordlist.txt\x00.evil", true},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			err := ValidateWordlistPath(tt.input)
			if (err != nil) != tt.wantErr {
				t.Errorf("ValidateWordlistPath(%q) error = %v, wantErr %v", tt.input, err, tt.wantErr)
			}
		})
	}
}

func TestValidateOutputPath(t *testing.T) {
	tests := []struct {
		name    string
		input   string
		wantErr bool
	}{
		{"empty allowed", "", false},
		{"relative output", "results.json", false},
		{"tmp output", "/tmp/results.json", false},
		{"path traversal", "../../../etc/passwd", true},
		{"null byte", "output.txt\x00", true},
		{"system path /etc/", "/etc/evil", true},
		{"system path /var/", "/var/www/shell.php", true},
		{"system path /usr/", "/usr/local/bin/backdoor", true},
		{"system path /root/", "/root/.ssh/id_rsa", true},
		{"system path /proc/", "/proc/self/mem", true},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			err := ValidateOutputPath(tt.input)
			if (err != nil) != tt.wantErr {
				t.Errorf("ValidateOutputPath(%q) error = %v, wantErr %v", tt.input, err, tt.wantErr)
			}
		})
	}
}

func TestValidateResolvers(t *testing.T) {
	tests := []struct {
		name    string
		input   string
		wantErr bool
	}{
		{"empty allowed", "", false},
		{"single resolver", "8.8.8.8", false},
		{"multiple resolvers", "8.8.8.8,1.1.1.1", false},
		{"multiple with spaces", "8.8.8.8, 1.1.1.1 , 9.9.9.9", false},
		{"invalid entry", "8.8.8.8,not-an-ip", true},
		{"all invalid", "foo,bar", true},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			err := ValidateResolvers(tt.input)
			if (err != nil) != tt.wantErr {
				t.Errorf("ValidateResolvers(%q) error = %v, wantErr %v", tt.input, err, tt.wantErr)
			}
		})
	}
}

func TestValidateConcurrency(t *testing.T) {
	tests := []struct {
		n       int
		wantErr bool
	}{
		{1, false},
		{1000, false},
		{10000, false},
		{0, true},
		{-1, true},
		{10001, true},
	}
	for _, tt := range tests {
		err := ValidateConcurrency(tt.n)
		if (err != nil) != tt.wantErr {
			t.Errorf("ValidateConcurrency(%d) err=%v wantErr=%v", tt.n, err, tt.wantErr)
		}
	}
}

func TestValidateTimeout(t *testing.T) {
	tests := []struct {
		n       int
		wantErr bool
	}{
		{1, false},
		{5, false},
		{300, false},
		{0, true},
		{-1, true},
		{301, true},
	}
	for _, tt := range tests {
		err := ValidateTimeout(tt.n)
		if (err != nil) != tt.wantErr {
			t.Errorf("ValidateTimeout(%d) err=%v wantErr=%v", tt.n, err, tt.wantErr)
		}
	}
}

func TestValidationError_Error(t *testing.T) {
	e := &ValidationError{Field: "domain", Message: "bad"}
	if got := e.Error(); got != "domain: bad" {
		t.Errorf("got %q, want %q", got, "domain: bad")
	}
}