package quark

import (
	"crypto/hmac"
	"crypto/rand"
	"crypto/sha256"
	"encoding/hex"
	"errors"
	"fmt"
	"net/http"
	"net/url"
	"sort"
	"strings"

	"github.com/higress-group/wasm-go/pkg/wrapper"
	"github.com/tidwall/gjson"

	"github.com/alibaba/higress/plugins/wasm-go/extensions/ai-search/engine"
)

type QuarkSearch struct {
	apiKey             string
	timeoutMillisecond uint32
	client             wrapper.HttpClient
	count              uint32
	optionArgs         map[string]string
	contentMode        string // "summary" or "full"
}

const (
	Path               = "/linked-retrieval/linked-retrieval-entry/v2/linkedRetrieval/commands/genericSearch"
	ContentSha256      = "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855" // for empty body
	Action             = "GenericSearch"
	Version            = "2024-11-11"
	SignatureAlgorithm = "ACS3-HMAC-SHA256"
	SignedHeaders      = "host;x-acs-action;x-acs-content-sha256;x-acs-date;x-acs-signature-nonce;x-acs-version"
)

func urlEncoding(rawStr string) string {
	encodedStr := url.PathEscape(rawStr)
	encodedStr = strings.ReplaceAll(encodedStr, "+", "%2B")
	encodedStr = strings.ReplaceAll(encodedStr, ":", "%3A")
	encodedStr = strings.ReplaceAll(encodedStr, "=", "%3D")
	encodedStr = strings.ReplaceAll(encodedStr, "&", "%26")
	encodedStr = strings.ReplaceAll(encodedStr, "$", "%24")
	encodedStr = strings.ReplaceAll(encodedStr, "@", "%40")
	// encodedStr := url.QueryEscape(rawStr)
	return encodedStr
}

func getSignature(stringToSign, secret string) string {
	h := hmac.New(sha256.New, []byte(secret))
	h.Write([]byte(stringToSign))
	hash := h.Sum(nil)
	return hex.EncodeToString(hash)
}

func getCanonicalHeaders(params map[string]string) string {
	paramArray := []string{}
	for k, v := range params {
		paramArray = append(paramArray, k+":"+v)
	}
	sort.Slice(paramArray, func(i, j int) bool {
		return paramArray[i] <= paramArray[j]
	})
	return strings.Join(paramArray, "\n") + "\n"
}

func getHasedString(input string) string {
	hash := sha256.Sum256([]byte(input))
	hashHex := hex.EncodeToString(hash[:])
	return hashHex
}

func generateHexID(length int) (string, error) {
	bytes := make([]byte, length/2)
	if _, err := rand.Read(bytes); err != nil {
		return "", err
	}
	return hex.EncodeToString(bytes), nil
}

func NewQuarkSearch(config *gjson.Result) (*QuarkSearch, error) {
	engine := &QuarkSearch{}
	engine.apiKey = config.Get("apiKey").String()
	if engine.apiKey == "" {
		return nil, errors.New("apiKey not found")
	}
	serviceName := config.Get("serviceName").String()
	if serviceName == "" {
		return nil, errors.New("serviceName not found")
	}
	servicePort := config.Get("servicePort").Int()
	if servicePort == 0 {
		return nil, errors.New("servicePort not found")
	}
	engine.count = uint32(config.Get("count").Int())
	if engine.count == 0 {
		engine.count = 10
	}
	engine.client = wrapper.NewClusterClient(wrapper.FQDNCluster{
		FQDN: serviceName,
		Port: servicePort,
	})
	engine.timeoutMillisecond = uint32(config.Get("timeoutMillisecond").Uint())
	if engine.timeoutMillisecond == 0 {
		engine.timeoutMillisecond = 5000
	}
	engine.optionArgs = map[string]string{}
	for key, value := range config.Get("optionArgs").Map() {
		valStr := value.String()
		if valStr != "" {
			engine.optionArgs[key] = value.String()
		}
	}
	engine.contentMode = config.Get("contentMode").String()
	if engine.contentMode == "" {
		engine.contentMode = "summary"
	}
	if engine.contentMode != "full" && engine.contentMode != "summary" {
		return nil, fmt.Errorf("contentMode is not valid:%s", engine.contentMode)
	}
	return engine, nil
}

func (g QuarkSearch) NeedExectue(ctx engine.SearchContext) bool {
	return ctx.EngineType == "" || ctx.EngineType == "internet"
}

func (g QuarkSearch) Client() wrapper.HttpClient {
	return g.client
}

func (g QuarkSearch) CallArgs(ctx engine.SearchContext) engine.CallArgs {
	queryUrl := fmt.Sprintf("https://cloud-iqs.aliyuncs.com/search/genericSearch?query=%s",
		url.QueryEscape(strings.Join(ctx.Querys, " ")))
	var extraArgs []string
	for key, value := range g.optionArgs {
		extraArgs = append(extraArgs, fmt.Sprintf("%s=%s", key, url.QueryEscape(value)))
	}
	if len(extraArgs) > 0 {
		queryUrl = fmt.Sprintf("%s&%s", queryUrl, strings.Join(extraArgs, "&"))
	}
	return engine.CallArgs{
		Method: http.MethodGet,
		Url:    queryUrl,
		Headers: [][2]string{
			{"Accept", "application/json"},
			{"X-API-Key", g.apiKey},
		},
		TimeoutMillisecond: g.timeoutMillisecond,
	}
}

func (g QuarkSearch) ParseResult(ctx engine.SearchContext, response []byte) []engine.SearchResult {
	jsonObj := gjson.ParseBytes(response)
	var results []engine.SearchResult
	for index, item := range jsonObj.Get("pageItems").Array() {
		var content string
		if g.contentMode == "full" {
			content = item.Get("markdownText").String()
			if content == "" {
				content = item.Get("mainText").String()
			}
		} else if g.contentMode == "summary" {
			content = item.Get("snippet").String()
		}
		result := engine.SearchResult{
			Title:   item.Get("title").String(),
			Link:    item.Get("link").String(),
			Content: content,
		}
		if result.Valid() && index < int(g.count) {
			results = append(results, result)
		}
	}
	return results
}