package engines

import (
	"context"
	"net/http"
	"strings"
	"testing"
	"time"

	"github.com/ashie/gosearch/internal/contracts"
)

func TestDuckDuckGoEngine_EmptyQuery(t *testing.T) {
	eng := &DuckDuckGoEngine{}
	req := contracts.SearchRequest{Query: ""}
	resp, err := eng.Search(context.Background(), req)
	if err != nil {
		t.Fatalf("unexpected error: %v", err)
	}
	if len(resp.Results) != 0 {
		t.Errorf("expected 0 results for empty query, got %d", len(resp.Results))
	}
}

func TestDuckDuckGoEngine_NilClient(t *testing.T) {
	eng := (*DuckDuckGoEngine)(nil)
	_, err := eng.Search(context.Background(), contracts.SearchRequest{Query: "test"})
	if err == nil {
		t.Error("expected error for nil engine")
	}
}

func TestDuckDuckGoEngine_UninitializedClient(t *testing.T) {
	eng := &DuckDuckGoEngine{}
	_, err := eng.Search(context.Background(), contracts.SearchRequest{Query: "test"})
	if err == nil {
		t.Error("expected error for uninitialized client")
	}
}

func TestDuckDuckGoEngine_Name(t *testing.T) {
	eng := &DuckDuckGoEngine{}
	if eng.Name() != "duckduckgo" {
		t.Errorf("expected 'duckduckgo', got %q", eng.Name())
	}
}

func TestDuckDuckGoRegion(t *testing.T) {
	tests := []struct {
		lang string
		want string
	}{
		{"", "us-en"},
		{"auto", "us-en"},
		{"en", "us-en"},
		{"de", "de-de"},
		{"fr", "fr-fr"},
		{"en-US", "us-en"},
		{"ja", "jp-jp"},
		{"unknown", "wt-wt"},
	}

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

func TestParseDuckDuckGoHTML(t *testing.T) {
	html := `<a class='result-link' href="https://example.com">Example Title</a>
	<td class='result-snippet'>This is a test snippet</td>
	<a class='result-link' href="https://example2.com">Second Result</a>
	<td class='result-snippet'>Another snippet here</td>`

	results, err := parseDuckDuckGoHTML(strings.NewReader(html))
	if err != nil {
		t.Fatalf("unexpected error: %v", err)
	}
	if len(results) != 2 {
		t.Fatalf("expected 2 results, got %d", len(results))
	}
	if results[0].Title != "Example Title" {
		t.Errorf("expected 'Example Title', got %q", results[0].Title)
	}
	if *results[0].URL != "https://example.com" {
		t.Errorf("expected 'https://example.com', got %q", *results[0].URL)
	}
}

func TestHtmlUnescape(t *testing.T) {
	tests := []struct {
		input    string
		expected string
	}{
		{"a&amp;b", "a&b"},
		{"a&lt;b", "a<b"},
		{"a&#39;b", "a'b"},
		{"normal", "normal"},
	}
	for _, tt := range tests {
		got := htmlUnescape(tt.input)
		if got != tt.expected {
			t.Errorf("htmlUnescape(%q) = %q, want %q", tt.input, got, tt.expected)
		}
	}
}

func TestDuckDuckGoEngine_LiveRequest(t *testing.T) {
	if testing.Short() {
		t.Skip("skipping live request")
	}

	client := &http.Client{}
	eng := &DuckDuckGoEngine{client: client}

	ctx, cancel := context.WithTimeout(context.Background(), 15*time.Second)
	defer cancel()

	resp, err := eng.Search(ctx, contracts.SearchRequest{
		Query: "golang programming",
	})
	if err != nil {
		t.Fatalf("live search failed: %v", err)
	}

	if resp.Query != "golang programming" {
		t.Errorf("query mismatch: %q", resp.Query)
	}
	t.Logf("duckduckgo returned %d results", len(resp.Results))
}