summaryrefslogtreecommitdiffstats
path: root/resources/page/pages.go
blob: ccfecdf2bc0950ad748327608d2c5b43cd2e6d52 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
// 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 page

import (
	"fmt"
	"math/rand"

	"github.com/gohugoio/hugo/compare"

	"github.com/gohugoio/hugo/resources/resource"
)

var (
	_ resource.ResourcesConverter = Pages{}
	_ compare.ProbablyEqer        = Pages{}
)

// Pages is a slice of pages. This is the most common list type in Hugo.
type Pages []Page

func (ps Pages) String() string {
	return fmt.Sprintf("Pages(%d)", len(ps))
}

// Used in tests.
func (ps Pages) shuffle() {
	for i := range ps {
		j := rand.Intn(i + 1)
		ps[i], ps[j] = ps[j], ps[i]
	}
}

// ToResources wraps resource.ResourcesConverter
func (pages Pages) ToResources() resource.Resources {
	r := make(resource.Resources, len(pages))
	for i, p := range pages {
		r[i] = p
	}
	return r
}

// ToPages tries to convert seq into Pages.
func ToPages(seq interface{}) (Pages, error) {
	if seq == nil {
		return Pages{}, nil
	}

	switch v := seq.(type) {
	case Pages:
		return v, nil
	case *Pages:
		return *(v), nil
	case WeightedPages:
		return v.Pages(), nil
	case PageGroup:
		return v.Pages, nil
	case []interface{}:
		pages := make(Pages, len(v))
		success := true
		for i, vv := range v {
			p, ok := vv.(Page)
			if !ok {
				success = false
				break
			}
			pages[i] = p
		}
		if success {
			return pages, nil
		}
	}

	return nil, fmt.Errorf("cannot convert type %T to Pages", seq)
}

func (p Pages) Group(key interface{}, in interface{}) (interface{}, error) {
	pages, err := ToPages(in)
	if err != nil {
		return nil, err
	}
	return PageGroup{Key: key, Pages: pages}, nil
}

// Len returns the number of pages in the list.
func (p Pages) Len() int {
	return len(p)
}

// ProbablyEq wraps comare.ProbablyEqer
func (pages Pages) ProbablyEq(other interface{}) bool {
	otherPages, ok := other.(Pages)
	if !ok {
		return false
	}

	if len(pages) != len(otherPages) {
		return false
	}

	step := 1

	for i := 0; i < len(pages); i += step {
		if !pages[i].Eq(otherPages[i]) {
			return false
		}

		if i > 50 {
			// This is most likely the same.
			step = 50
		}
	}

	return true
}

func (ps Pages) removeFirstIfFound(p Page) Pages {
	ii := -1
	for i, pp := range ps {
		if p.Eq(pp) {
			ii = i
			break
		}
	}

	if ii != -1 {
		ps = append(ps[:ii], ps[ii+1:]...)
	}
	return ps
}

// PagesFactory somehow creates some Pages.
// We do a lot of lazy Pages initialization in Hugo, so we need a type.
type PagesFactory func() Pages