63 lines
1.4 KiB
Go
63 lines
1.4 KiB
Go
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// Copyright 2016 Minho. All rights reserved.
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// Copyright 2021 Flamego. All rights reserved.
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// Use of this source code is governed by a MIT-style
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// license that can be found in the LICENSE file.
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package captchautil
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import (
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"embed"
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"path"
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"sync"
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"github.com/golang/freetype"
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"github.com/golang/freetype/truetype"
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"github.com/pkg/errors"
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)
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//go:embed fonts/*.ttf
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var fonts embed.FS
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var (
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fontFamilyNames []string
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fontFamilies map[string]*truetype.Font
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fontFamilyOnce sync.Once
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fontFamilyErr error
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)
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func randFontFamily() (*truetype.Font, error) {
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fontFamilyOnce.Do(func() {
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files, err := fonts.ReadDir("fonts")
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if err != nil {
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fontFamilyErr = errors.Wrap(err, "read directory")
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return
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}
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fontFamilyNames = make([]string, 0, len(files))
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fontFamilies = make(map[string]*truetype.Font, len(files))
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for _, fi := range files {
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data, err := fonts.ReadFile(path.Join("fonts", fi.Name()))
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if err != nil {
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fontFamilyErr = errors.Wrapf(err, "read file %q", fi.Name())
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return
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}
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f, err := freetype.ParseFont(data)
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if err != nil {
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fontFamilyErr = errors.Wrapf(err, "parse font %q", fi.Name())
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return
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}
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fontFamilyNames = append(fontFamilyNames, fi.Name())
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fontFamilies[fi.Name()] = f
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}
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})
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if fontFamilyErr != nil {
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return nil, fontFamilyErr
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}
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name := fontFamilyNames[r.Intn(len(fontFamilyNames))]
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return fontFamilies[name], nil
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}
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