package service

import (
	"case-api/api/dao"
)

type BasicSensitiveWordService struct {
}

type TrieNode struct {
	Children map[rune]*TrieNode
	IsEnd    bool
}

type Trie struct {
	Root *TrieNode
}

func (t *Trie) Insert(word string) {
	node := t.Root
	for _, ch := range word {
		if node.Children[ch] == nil {
			node.Children[ch] = &TrieNode{Children: make(map[rune]*TrieNode)}
		}
		node = node.Children[ch]
	}
	node.IsEnd = true
}

func (t *Trie) Filter(comment string) (s string, isSensitive int) {
	runes := []rune(comment)
	n := len(runes)
	for i := 0; i < n; i++ {
		node := t.Root
		j := i
		for j < n && node.Children[runes[j]] != nil {
			node = node.Children[runes[j]]
			j++
			if node.IsEnd {
				for k := i; k < j; k++ {
					runes[k] = '*'
					isSensitive = 1
				}
				break
			}
		}
	}
	return string(runes), isSensitive
}

// Filter 过滤敏感词
func (r *BasicSensitiveWordService) Filter(comment string) (s string, isSensitive int) {
	basicSensitiveWordDao := dao.BasicSensitiveWordDao{}
	maps := make(map[string]interface{})
	basicSensitiveWords, _ := basicSensitiveWordDao.GetBasicSensitiveWordList(maps)
	if len(basicSensitiveWords) <= 0 {
		return comment, isSensitive
	}

	trie := &Trie{Root: &TrieNode{Children: make(map[rune]*TrieNode)}}
	for _, word := range basicSensitiveWords {
		trie.Insert(word.Word)
	}

	comment, isSensitive = trie.Filter(comment)

	trie = &Trie{}
	return comment, isSensitive
}