path_trie.go

// https://github.com/dghubble/trie
//The MIT License (MIT)
//
//Copyright (c) 2014 Dalton Hubble
//
//Permission is hereby granted, free of charge, to any person obtaining a copy
//of this software and associated documentation files (the "Software"), to deal
//in the Software without restriction, including without limitation the rights
//to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
//copies of the Software, and to permit persons to whom the Software is
//furnished to do so, subject to the following conditions:
//
//The above copyright notice and this permission notice shall be included in
//all copies or substantial portions of the Software.
//
//THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
//IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
//FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
//AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
//LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
//OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
//THE SOFTWARE.

package tequila

import "strings"

type StringSegmenter func(key string, start int) (segment string, nextIndex int)

func PathSegmenter(path string, start int) (segment string, next int) {
	if len(path) == 0 || start < 0 || start > len(path)-1 {
		return "", -1
	}
	end := strings.IndexRune(path[start+1:], '/') // next '/' after 0th rune
	if end == -1 {
		return path[start:], -1
	}
	return path[start : start+end+1], start + end + 1
}

type PathTrie struct {
	segmenter StringSegmenter
	Value     string
	Children  map[string]*PathTrie
}

func NewPathTrie() *PathTrie {
	return &PathTrie{
		segmenter: PathSegmenter,
	}
}

func (trie *PathTrie) Put(key string) {
	node := trie
	for part, i := trie.segmenter(key, 0); part != ""; part, i = trie.segmenter(key, i) {
		child, _ := node.Children[part]
		if child == nil {
			if node.Children == nil {
				node.Children = map[string]*PathTrie{}
			}
			child = NewPathTrie()
			node.Children[part] = child
		}

		child.Value = strings.ReplaceAll(part, "/", "")
		node = child
	}
}