package search

import (
	"context"
	"encoding/json"
	"fmt"
	"io"
	"net/http"
	"net/url"
	"time"
)

type SearXNGClient struct {
	baseURL string
	client  *http.Client
}

type SearXNGResult struct {
	Title   string `json:"title"`
	URL     string `json:"url"`
	Content string `json:"content"`
	Engine  string `json:"engine"`
}

type SearXNGResponse struct {
	Results []SearXNGResult `json:"results"`
}

func NewSearXNGClient(baseURL string) *SearXNGClient {
	return &SearXNGClient{
		baseURL: baseURL,
		client:  &http.Client{Timeout: 15 * time.Second},
	}
}

func (c *SearXNGClient) Search(ctx context.Context, query string, limit int) ([]SearXNGResult, error) {
	u, err := url.Parse(c.baseURL + "/search")
	if err != nil {
		return nil, fmt.Errorf("parse url: %w", err)
	}
	q := u.Query()
	q.Set("q", query)
	q.Set("format", "json")
	q.Set("language", "ru-RU,en-US")
	q.Set("categories", "general,news")
	if limit > 0 {
		q.Set("pageno", "1")
	}
	u.RawQuery = q.Encode()

	req, err := http.NewRequestWithContext(ctx, "GET", u.String(), nil)
	if err != nil {
		return nil, fmt.Errorf("create request: %w", err)
	}
	req.Header.Set("User-Agent", "DeepRes/1.0")

	resp, err := c.client.Do(req)
	if err != nil {
		return nil, fmt.Errorf("search request: %w", err)
	}
	defer resp.Body.Close()

	if resp.StatusCode != http.StatusOK {
		body, _ := io.ReadAll(resp.Body)
		return nil, fmt.Errorf("searxng returned %d: %s", resp.StatusCode, string(body))
	}

	body, err := io.ReadAll(resp.Body)
	if err != nil {
		return nil, fmt.Errorf("read response: %w", err)
	}

	var sr SearXNGResponse
	if err := json.Unmarshal(body, &sr); err != nil {
		return nil, fmt.Errorf("parse response: %w", err)
	}

	if len(sr.Results) > limit {
		sr.Results = sr.Results[:limit]
	}
	return sr.Results, nil
}

// SearchWithVariations запускает несколько поисковых запросов с разными формулировками
func (c *SearXNGClient) SearchWithVariations(ctx context.Context, baseQuery string, variations []string, limit int) ([]SearXNGResult, error) {
	seen := make(map[string]bool)
	var allResults []SearXNGResult

	queries := append([]string{baseQuery}, variations...)
	for _, q := range queries {
		results, err := c.Search(ctx, q, limit)
		if err != nil {
			// Логируем но продолжаем — один упавший запрос не ломает весь ресерч
			continue
		}
		for _, r := range results {
			if !seen[r.URL] {
				seen[r.URL] = true
				allResults = append(allResults, r)
			}
		}
	}
	return allResults, nil
}