soumya92/barista

// Copyright 2017 Google Inc.
//
// 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 fontawesome provides support for FontAwesome Icons
from https://github.com/FortAwesome/Font-Awesome

It uses metadata/icons.yml to get the list of icons,
and requires fonts/fontawesome-webfont.ttf to be installed.
*/
package fontawesome

import (
    "fmt"
    "path/filepath"

    "github.com/soumya92/barista/pango"
    "github.com/soumya92/barista/pango/icons"

    "github.com/spf13/afero"
    "gopkg.in/yaml.v2"
)

type faMetadata struct {
    Code   string   `yaml:"unicode"`
    Styles []string `yaml:"styles"`
}

var fs = afero.NewOsFs()

// Load initialises the fontawesome icon provider from the given repo.
func Load(repoPath string) error {
    f, err := fs.Open(filepath.Join(repoPath, "metadata/icons.yml"))
    if err != nil {
        return err
    }
    defer f.Close()

    // Defaults to solid since that style has the most icons available.
    faSolid := icons.NewProvider("fa")
    faSolid.Font("Font Awesome 5 Free")
    faSolid.AddStyle(func(n *pango.Node) { n.Weight(900) })

    faBrands := icons.NewProvider("fab")
    faBrands.Font("Font Awesome 5 Brands")

    faRegular := icons.NewProvider("far")
    faRegular.Font("Font Awesome 5 Free")

    styles := map[string]*icons.Provider{
        "solid":   faSolid,
        "regular": faRegular,
        "brands":  faBrands,
    }

    var glyphs map[string]faMetadata
    err = yaml.NewDecoder(f).Decode(&glyphs)
    if err != nil {
        return err
    }
    for name, meta := range glyphs {
        for _, style := range meta.Styles {
            p, ok := styles[style]
            if !ok {
                return fmt.Errorf("Unknown FontAwesome style: '%s'", style)
            }
            err = p.Hex(name, meta.Code)
            if err != nil {
                return err
            }
        }
    }
    return nil
}