// Package model define model struct of model runtime service
package model

import (
	"context"
	"fmt"
	"math"
	"strings"

	"modelRT/constants"
	"modelRT/diagram"
	"modelRT/logger"

	"github.com/RediSearch/redisearch-go/v2/redisearch"
	redigo "github.com/gomodule/redigo/redis"
	"github.com/redis/go-redis/v9"
)

var ac *redisearch.Autocompleter

// InitAutocompleterWithPool define func of initialize the Autocompleter with redigo pool
func InitAutocompleterWithPool(pool *redigo.Pool) {
	ac = redisearch.NewAutocompleterFromPool(pool, constants.RedisSearchDictName)
}

// RedisSearchRecommend define func of redis search by input string and return recommend results
func RedisSearchRecommend(ctx context.Context, input string) ([]string, bool, error) {
	rdb := diagram.GetRedisClientInstance()

	if input == "" {
		// return all grid tagname
		return getKeyBySpecificsLevel(ctx, rdb, 1, input)
	}

	inputSlice := strings.Split(input, ".")
	inputSliceLen := len(inputSlice)

	switch inputSliceLen {
	case 1:
		// grid tagname search
		gridSearchInput := inputSlice[0]
		gridExists, err := rdb.SIsMember(ctx, constants.RedisAllGridSetKey, gridSearchInput).Result()
		if err != nil {
			logger.Error(ctx, "check grid key exist failed ", "grid_key", input, "error", err)
			return []string{}, false, err
		}

		if gridExists {
			return []string{"."}, false, nil
		}

		// start grid tagname fuzzy search
		recommends, err := runFuzzySearch(ctx, gridSearchInput, inputSliceLen)
		if err != nil {
			logger.Error(ctx, "fuzzy search failed for level 1", "search_input", gridSearchInput, "error", err)
			return []string{}, false, err
		}

		if len(recommends) > 0 {
			return recommends, true, nil
		}
		return []string{}, true, nil

	case 2:
		return handleLevelFuzzySearch(ctx, rdb, 2, constants.RedisAllZoneSetKey, inputSlice)
	case 3:
		return handleLevelFuzzySearch(ctx, rdb, 3, constants.RedisAllStationSetKey, inputSlice)
	case 4:
		return handleLevelFuzzySearch(ctx, rdb, 4, constants.RedisAllCompNSPathSetKey, inputSlice)
	case 5:
		return handleLevelFuzzySearch(ctx, rdb, 5, constants.RedisAllCompTagSetKey, inputSlice)
	case 6:
		return handleLevelFuzzySearch(ctx, rdb, 6, constants.RedisAllConfigSetKey, inputSlice)
	case 7:
		return handleLevelFuzzySearch(ctx, rdb, 7, constants.RedisAllMeasTagSetKey, inputSlice)

	default:
		logger.Error(ctx, "unsupport length of search input", "input_len", inputSliceLen)
		return []string{}, false, nil
	}
}

func getKeyBySpecificsLevel(ctx context.Context, rdb *redis.Client, inputLen int, input string) ([]string, bool, error) {
	queryKey := getSpecificKeyByLength(inputLen, input)
	results, err := rdb.SMembers(ctx, queryKey).Result()
	if err != nil {
		return []string{}, false, fmt.Errorf("get all keys failed, error: %w", err)
	}
	return results, false, nil
}

func combineQueryResultByInput(inputSliceLen int, inputSlice []string, queryResults []string) []string {
	prefixs := make([]string, 0, len(inputSlice))
	recommandResults := make([]string, 0, len(queryResults))
	switch inputSliceLen {
	case 2:
		prefixs = []string{inputSlice[0]}
	case 3:
		prefixs = inputSlice[0:2]
	case 4:
		prefixs = inputSlice[0:3]
	case 5:
		prefixs = inputSlice[0:4]
	case 6:
		prefixs = inputSlice[0:5]
	case 7:
		prefixs = inputSlice[0:6]
	default:
		return []string{}
	}

	for _, queryResult := range queryResults {
		combineStrs := make([]string, 0, len(inputSlice))
		combineStrs = append(combineStrs, prefixs...)
		combineStrs = append(combineStrs, queryResult)
		recommandResult := strings.Join(combineStrs, ".")
		recommandResults = append(recommandResults, recommandResult)
	}
	return recommandResults
}

func getSpecificKeyByLength(inputLen int, input string) string {
	switch inputLen {
	case 1:
		return constants.RedisAllGridSetKey
	case 2:
		return fmt.Sprintf(constants.RedisSpecGridZoneSetKey, input)
	case 3:
		return fmt.Sprintf(constants.RedisSpecZoneStationSetKey, input)
	case 4:
		return fmt.Sprintf(constants.RedisSpecStationCompNSPATHSetKey, input)
	case 5:
		return fmt.Sprintf(constants.RedisSpecStationCompTagSetKey, input)
	case 6:
		return constants.RedisAllConfigSetKey
	case 7:
		return fmt.Sprintf(constants.RedisSpecCompTagMeasSetKey, input)
	default:
		return constants.RedisAllGridSetKey
	}
}

// handleLevelFuzzySearch define func to process recommendation logic for specific levels(level >= 2)
func handleLevelFuzzySearch(ctx context.Context, rdb *redis.Client, level int, keySetKey string, inputSlice []string) ([]string, bool, error) {
	searchInputIndex := level - 1
	searchInput := inputSlice[searchInputIndex]

	if searchInput == "" {
		var specificalKey string
		specificalKeyIndex := searchInputIndex - 1
		if specificalKeyIndex >= 0 {
			specificalKey = inputSlice[specificalKeyIndex]
		}

		allResults, isFuzzy, err := getKeyBySpecificsLevel(ctx, rdb, level, specificalKey)
		if err != nil {
			return []string{}, false, err
		}
		recommandResults := combineQueryResultByInput(level, inputSlice, allResults)
		return recommandResults, isFuzzy, nil
	}

	keyExists, err := rdb.SIsMember(ctx, keySetKey, searchInput).Result()
	if err != nil {
		logger.Error(ctx, "check key exist failed ", "key", searchInput, "error", err)
		return []string{}, false, err
	}

	if keyExists {
		return []string{"."}, false, nil
	}

	// start redis fuzzy search
	recommends, err := runFuzzySearch(ctx, searchInput, level)
	if err != nil {
		logger.Error(ctx, "fuzzy search failed for level", "level", level, "search_input", searchInput, "error", err)
		return []string{}, false, err
	}

	if len(recommends) == 0 {
		logger.Error(ctx, "fuzzy search without result", "level", level, "search_input", searchInput, "error", err)
		return []string{}, true, nil
	}
	return combineQueryResultByInput(level, inputSlice, recommends), true, nil
}

// runFuzzySearch define func to process redis fuzzy search
func runFuzzySearch(ctx context.Context, searchInput string, inputSliceLen int) ([]string, error) {
	searchInputLen := len(searchInput)

	for searchInputLen != 0 {
		results, err := ac.SuggestOpts(searchInput, redisearch.SuggestOptions{
			Num:          math.MaxInt16,
			Fuzzy:        true,
			WithScores:   false,
			WithPayloads: false,
		})
		if err != nil {
			logger.Error(ctx, "query key by redis fuzzy search failed", "query_key", searchInput, "error", err)
			return nil, fmt.Errorf("redisearch suggest failed: %w", err)
		}

		if len(results) == 0 {
			// 如果没有结果，退一步（删除最后一个字节）并继续循环
			// TODO 考虑使用其他方式代替 for 循环退一字节的查询方式
			searchInput = searchInput[:len(searchInput)-1]
			searchInputLen = len(searchInput)
			continue
		}

		var recommends []string
		for _, result := range results {
			termSlice := strings.Split(result.Term, ".")
			if len(termSlice) <= inputSliceLen {
				recommends = append(recommends, result.Term)
			}
		}
		return recommends, nil
	}
	return []string{}, nil
}

// RedisSearchRecommend1 define func of redis search by input string and return recommend results
func RedisSearchRecommend1(ctx context.Context, input string) ([]string, bool, error) {
	rdb := diagram.GetRedisClientInstance()

	if input == "" {
		// 返回所有 grid 名
		return getKeyBySpecificsLevel(ctx, rdb, 1, input)
	}

	inputSlice := strings.Split(input, ".")
	inputSliceLen := len(inputSlice)

	switch inputSliceLen {
	case 1:
		// grid tagname search
		gridSearchInput := inputSlice[0]
		gridExists, err := rdb.SIsMember(ctx, constants.RedisAllGridSetKey, gridSearchInput).Result()
		if err != nil {
			logger.Error(ctx, "check grid key exist failed ", "grid_key", input, "error", err)
			return []string{}, false, err
		}

		if gridExists {
			return []string{"."}, false, err
		}

		// start grid tagname fuzzy search
		searchInput := gridSearchInput
		searchInputLen := len(searchInput)
		for searchInputLen != 0 && !gridExists {
			results, err := ac.SuggestOpts(searchInput, redisearch.SuggestOptions{
				Num:          math.MaxInt16,
				Fuzzy:        true,
				WithScores:   false,
				WithPayloads: false,
			})
			if err != nil {
				logger.Error(ctx, "query grid key by redis fuzzy search failed", "query_key", searchInput, "error", err)
				return []string{}, false, err
			}

			if len(results) == 0 {
				// TODO 考虑使用其他方式代替 for 循环退一字节的查询方式
				searchInput = searchInput[:len(searchInput)-1]
				searchInputLen = len(searchInput)
				continue
			}

			var recommends []string
			for _, result := range results {
				termSlice := strings.Split(result.Term, ".")
				if len(termSlice) <= inputSliceLen {
					recommends = append(recommends, result.Term)
				}
			}
			// return fuzzy search results
			return recommends, true, nil
		}
	case 2:
		// zone tagname search
		zoneSearchInput := inputSlice[1]
		if zoneSearchInput == "" {
			specificalGrid := inputSlice[0]
			allZones, isFuzzy, err := getKeyBySpecificsLevel(ctx, rdb, inputSliceLen, specificalGrid)
			recommandResults := combineQueryResultByInput(inputSliceLen, inputSlice, allZones)
			return recommandResults, isFuzzy, err
		}

		zoneExists, err := rdb.SIsMember(ctx, constants.RedisAllZoneSetKey, zoneSearchInput).Result()
		if err != nil {
			logger.Error(ctx, "check zone key exist failed ", "zone_key", zoneSearchInput, "error", err)
			return []string{}, false, err
		}

		if zoneExists {
			return []string{"."}, false, err
		}

		// start zone tagname fuzzy search
		searchInput := zoneSearchInput
		searchInputLen := len(searchInput)
		for searchInputLen != 0 && !zoneExists {
			results, err := ac.SuggestOpts(searchInput, redisearch.SuggestOptions{
				Num:          math.MaxInt16,
				Fuzzy:        true,
				WithScores:   false,
				WithPayloads: false,
			})
			if err != nil {
				logger.Error(ctx, "query zone key by redis fuzzy search failed", "query_key", searchInput, "error", err)
				return []string{}, false, err
			}

			if len(results) == 0 {
				// TODO 考虑使用其他方式代替 for 循环退一字节的查询方式
				searchInput = searchInput[:len(searchInput)-1]
				searchInputLen = len(searchInput)
				continue
			}

			var recommends []string
			for _, result := range results {
				termSlice := strings.Split(result.Term, ".")
				if len(termSlice) <= inputSliceLen {
					recommends = append(recommends, result.Term)
				}
			}
			// return fuzzy search results
			return combineQueryResultByInput(inputSliceLen, inputSlice, recommends), true, nil
		}
	case 3:
		// station tagname search
		stationSearchInput := inputSlice[2]
		if stationSearchInput == "" {
			specificalZone := inputSlice[1]
			allStations, isFuzzy, err := getKeyBySpecificsLevel(ctx, rdb, inputSliceLen, specificalZone)
			recommandResults := combineQueryResultByInput(inputSliceLen, inputSlice, allStations)
			return recommandResults, isFuzzy, err
		}

		stationExists, err := rdb.SIsMember(ctx, constants.RedisAllStationSetKey, stationSearchInput).Result()
		if err != nil {
			logger.Error(ctx, "check station key exist failed ", "station_key", stationSearchInput, "error", err)
			return []string{}, false, err
		}

		if stationExists {
			return []string{"."}, false, err
		}

		// start station tagname fuzzy search
		searchInput := stationSearchInput
		searchInputLen := len(searchInput)
		for searchInputLen != 0 && !stationExists {
			results, err := ac.SuggestOpts(searchInput, redisearch.SuggestOptions{
				Num:          math.MaxInt16,
				Fuzzy:        true,
				WithScores:   false,
				WithPayloads: false,
			})
			if err != nil {
				logger.Error(ctx, "query station key by redis fuzzy search failed", "query_key", searchInput, "error", err)
				return []string{}, false, err
			}

			if len(results) == 0 {
				// TODO 考虑使用其他方式代替 for 循环退一字节的查询方式
				searchInput = searchInput[:len(searchInput)-1]
				searchInputLen = len(searchInput)
				continue
			}

			var recommends []string
			for _, result := range results {
				termSlice := strings.Split(result.Term, ".")
				if len(termSlice) <= inputSliceLen {
					recommends = append(recommends, result.Term)
				}
			}
			// return fuzzy search results
			return combineQueryResultByInput(inputSliceLen, inputSlice, recommends), true, nil
		}
	case 4:
		// component nspath search
		compNSPSearchInput := inputSlice[3]
		if compNSPSearchInput == "" {
			specificalStation := inputSlice[2]
			allCompNSPaths, isFuzzy, err := getKeyBySpecificsLevel(ctx, rdb, inputSliceLen, specificalStation)
			recommandResults := combineQueryResultByInput(inputSliceLen, inputSlice, allCompNSPaths)
			return recommandResults, isFuzzy, err
		}

		compNSPathExists, err := rdb.SIsMember(ctx, constants.RedisAllCompNSPathSetKey, compNSPSearchInput).Result()
		if err != nil {
			logger.Error(ctx, "check component nspath key exist failed ", "component_nspath_key", compNSPSearchInput, "error", err)
			return []string{}, false, err
		}

		if compNSPathExists {
			return []string{"."}, false, err
		}

		// start grid fuzzy search
		searchInput := compNSPSearchInput
		searchInputLen := len(searchInput)
		for searchInputLen != 0 && !compNSPathExists {
			results, err := ac.SuggestOpts(searchInput, redisearch.SuggestOptions{
				Num:          math.MaxInt16,
				Fuzzy:        true,
				WithScores:   false,
				WithPayloads: false,
			})
			if err != nil {
				logger.Error(ctx, "query component nspath key by redis fuzzy search failed", "query_key", searchInput, "error", err)
				return []string{}, false, err
			}

			if len(results) == 0 {
				// TODO 考虑使用其他方式代替 for 循环退一字节的查询方式
				searchInput = searchInput[:len(searchInput)-1]
				searchInputLen = len(searchInput)
				continue
			}

			var recommends []string
			for _, result := range results {
				termSlice := strings.Split(result.Term, ".")
				if len(termSlice) <= inputSliceLen {
					recommends = append(recommends, result.Term)
				}
			}
			// return fuzzy search results
			return combineQueryResultByInput(inputSliceLen, inputSlice, recommends), true, nil
		}
	case 5:
		// component tag search
		compTagSearchInput := inputSlice[4]
		if compTagSearchInput == "" {
			// TODO 优化考虑是否使用 station 作为 key 的一部分
			specificalStation := inputSlice[2]
			allCompNSPaths, isFuzzy, err := getKeyBySpecificsLevel(ctx, rdb, inputSliceLen, specificalStation)
			recommandResults := combineQueryResultByInput(inputSliceLen, inputSlice, allCompNSPaths)
			return recommandResults, isFuzzy, err
		}

		compTagExists, err := rdb.SIsMember(ctx, constants.RedisAllCompTagSetKey, compTagSearchInput).Result()
		if err != nil {
			logger.Error(ctx, "check component tag key exist failed ", "component_tag_key", compTagSearchInput, "error", err)
			return []string{}, false, err
		}

		if compTagExists {
			return []string{"."}, false, err
		}

		// start grid fuzzy search
		searchInput := compTagSearchInput
		searchInputLen := len(searchInput)
		for searchInputLen != 0 && !compTagExists {
			results, err := ac.SuggestOpts(searchInput, redisearch.SuggestOptions{
				Num:          math.MaxInt16,
				Fuzzy:        true,
				WithScores:   false,
				WithPayloads: false,
			})
			if err != nil {
				logger.Error(ctx, "query component tag key by redis fuzzy search failed", "query_key", searchInput, "error", err)
				return []string{}, false, err
			}

			if len(results) == 0 {
				// TODO 考虑使用其他方式代替 for 循环退一字节的查询方式
				searchInput = searchInput[:len(searchInput)-1]
				searchInputLen = len(searchInput)
				continue
			}

			var recommends []string
			for _, result := range results {
				termSlice := strings.Split(result.Term, ".")
				if len(termSlice) <= inputSliceLen {
					recommends = append(recommends, result.Term)
				}
			}
			// return fuzzy search results
			return combineQueryResultByInput(inputSliceLen, inputSlice, recommends), true, nil
		}
	case 6:
		// configuration search
		// TODO 优化
		configSearchInput := inputSlice[5]
		if configSearchInput == "" {
			allCompNSPaths, isFuzzy, err := getKeyBySpecificsLevel(ctx, rdb, inputSliceLen, "")
			recommandResults := combineQueryResultByInput(inputSliceLen, inputSlice, allCompNSPaths)
			return recommandResults, isFuzzy, err
		}

		configExists, err := rdb.SIsMember(ctx, constants.RedisAllConfigSetKey, configSearchInput).Result()
		if err != nil {
			logger.Error(ctx, "check config key exist failed ", "config_key", configSearchInput, "error", err)
			return []string{}, false, err
		}

		if configExists {
			return []string{"."}, false, err
		}

		// start grid fuzzy search
		searchInput := configSearchInput
		searchInputLen := len(searchInput)
		for searchInputLen != 0 && !configExists {
			results, err := ac.SuggestOpts(searchInput, redisearch.SuggestOptions{
				Num:          math.MaxInt16,
				Fuzzy:        true,
				WithScores:   false,
				WithPayloads: false,
			})
			if err != nil {
				logger.Error(ctx, "query config key by redis fuzzy search failed", "query_key", searchInput, "error", err)
				return []string{}, false, err
			}

			if len(results) == 0 {
				// TODO 考虑使用其他方式代替 for 循环退一字节的查询方式
				searchInput = searchInput[:len(searchInput)-1]
				searchInputLen = len(searchInput)
				continue
			}

			var recommends []string
			for _, result := range results {
				termSlice := strings.Split(result.Term, ".")
				if len(termSlice) <= inputSliceLen {
					recommends = append(recommends, result.Term)
				}
			}
			// return fuzzy search results
			return combineQueryResultByInput(inputSliceLen, inputSlice, recommends), true, nil
		}
	case 7:
		// measurement search
		measSearchInput := inputSlice[6]
		if measSearchInput == "" {
			// use compoent tag for redis unique key prefix
			specificalCompTag := inputSlice[4]
			allMeasTags, isFuzzy, err := getKeyBySpecificsLevel(ctx, rdb, inputSliceLen, specificalCompTag)
			recommandResults := combineQueryResultByInput(inputSliceLen, inputSlice, allMeasTags)
			return recommandResults, isFuzzy, err
		}

		measTagExists, err := rdb.SIsMember(ctx, constants.RedisAllMeasTagSetKey, measSearchInput).Result()
		if err != nil {
			logger.Error(ctx, "check component tag key exist failed ", "component_tag_key", measSearchInput, "error", err)
			return []string{}, false, err
		}

		if measTagExists {
			return []string{"."}, false, err
		}

		// start measurement tag fuzzy search
		searchInput := measSearchInput
		searchInputLen := len(searchInput)
		for searchInputLen != 0 && !measTagExists {
			results, err := ac.SuggestOpts(searchInput, redisearch.SuggestOptions{
				Num:          math.MaxInt16,
				Fuzzy:        true,
				WithScores:   false,
				WithPayloads: false,
			})
			if err != nil {
				logger.Error(ctx, "query measurement tag key by redis fuzzy search failed", "query_key", searchInput, "error", err)
				return []string{}, false, err
			}

			if len(results) == 0 {
				// TODO 考虑使用其他方式代替 for 循环退一字节的查询方式
				searchInput = searchInput[:len(searchInput)-1]
				searchInputLen = len(searchInput)
				continue
			}

			var recommends []string
			for _, result := range results {
				termSlice := strings.Split(result.Term, ".")
				if len(termSlice) <= inputSliceLen {
					recommends = append(recommends, result.Term)
				}
			}
			// return fuzzy search results
			return combineQueryResultByInput(inputSliceLen, inputSlice, recommends), true, nil
		}
	default:
		logger.Error(ctx, "unsupport length of search input", "input_len", inputSliceLen)
		return []string{}, false, nil
	}
	return []string{}, false, nil
}