hugo/tpl/tplimpl/shortcodes.go
2020-12-03 13:12:58 +01:00

154 lines
3.4 KiB
Go

// Copyright 2019 The Hugo Authors. All rights reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package tplimpl
import (
"strings"
"github.com/gohugoio/hugo/tpl"
)
// Currently lang, outFormat, suffix
const numTemplateVariants = 3
type shortcodeVariant struct {
// The possible variants: lang, outFormat, suffix
// gtag
// gtag.html
// gtag.no.html
// gtag.no.amp.html
// A slice of length numTemplateVariants.
variants []string
ts *templateState
}
type shortcodeTemplates struct {
variants []shortcodeVariant
}
func (s *shortcodeTemplates) indexOf(variants []string) int {
L:
for i, v1 := range s.variants {
for i, v2 := range v1.variants {
if v2 != variants[i] {
continue L
}
}
return i
}
return -1
}
func (s *shortcodeTemplates) fromVariants(variants tpl.TemplateVariants) (shortcodeVariant, bool) {
return s.fromVariantsSlice([]string{
variants.Language,
strings.ToLower(variants.OutputFormat.Name),
variants.OutputFormat.MediaType.Suffix(),
})
}
func (s *shortcodeTemplates) fromVariantsSlice(variants []string) (shortcodeVariant, bool) {
var (
bestMatch shortcodeVariant
bestMatchWeight int
)
for _, variant := range s.variants {
w := s.compareVariants(variants, variant.variants)
if bestMatchWeight == 0 || w > bestMatchWeight {
bestMatch = variant
bestMatchWeight = w
}
}
return bestMatch, true
}
// calculate a weight for two string slices of same length.
// higher value means "better match".
func (s *shortcodeTemplates) compareVariants(a, b []string) int {
weight := 0
k := len(a)
for i, av := range a {
bv := b[i]
if av == bv {
// Add more weight to the left side (language...).
weight = weight + k - i
} else {
weight--
}
}
return weight
}
func templateVariants(name string) []string {
_, variants := templateNameAndVariants(name)
return variants
}
func templateNameAndVariants(name string) (string, []string) {
variants := make([]string, numTemplateVariants)
parts := strings.Split(name, ".")
if len(parts) <= 1 {
// No variants.
return name, variants
}
name = parts[0]
parts = parts[1:]
lp := len(parts)
start := len(variants) - lp
for i, j := start, 0; i < len(variants); i, j = i+1, j+1 {
variants[i] = parts[j]
}
if lp > 1 && lp < len(variants) {
for i := lp - 1; i > 0; i-- {
variants[i-1] = variants[i]
}
}
if lp == 1 {
// Suffix only. Duplicate it into the output format field to
// make HTML win over AMP.
variants[len(variants)-2] = variants[len(variants)-1]
}
return name, variants
}
func resolveTemplateType(name string) templateType {
if isShortcode(name) {
return templateShortcode
}
if strings.Contains(name, "partials/") {
return templatePartial
}
return templateUndefined
}
func isShortcode(name string) bool {
return strings.Contains(name, shortcodesPathPrefix)
}
func isInternal(name string) bool {
return strings.HasPrefix(name, internalPathPrefix)
}