package notes

import (

"fmt"

"github.com/pkg/errors"

"io"

"sort"

"strings"

"gopkg.in/alecthomas/kingpin.v2"

)

// TagsCmd represents `notes tags` command. Each public fields represent options of the command

// Out field represents where this command should output.

type TagsCmd struct {

cli *kingpin.CmdClause

Config *Config

// Category is a category name of tags. If this value is empty, tags of all categories will be output

Category string

// Out is a writer to write output of this command. Kind of stdout is expected

Out io.Writer

}

func (cmd *TagsCmd) defineCLI(app *kingpin.Application) {

cmd.cli = app.Command("tags", "List all tags")

cmd.cli.Arg("category", "Show tags of specified category. If not specified, all tags are output").StringVar(&cmd.Category)

}

func (cmd *TagsCmd) matchesCmdline(cmdline string) bool {

return cmd.cli.FullCommand() == cmdline

}

// Do runs `notes tags` command and returns an error if occurs

func (cmd *TagsCmd) Do() error {

saw := map[string]struct{}{}

tags := []string{}

cats, err := CollectCategories(cmd.Config, 0)

if err != nil {

return err

}

if cmd.Category != "" {

// Even if category is specified, we fetch all categories since error message requires

// all category names for suggestion.

cat, ok := cats[cmd.Category]

if !ok {

ns := cats.Names()

return errors.Errorf("Category '%s' does not exist. All categories are %s", cmd.Category, strings.Join(ns, ", "))

}

cats = Categories{cmd.Category: cat}

}

for _, cat := range cats {

notes, err := cat.Notes(cmd.Config)

if err != nil {

return err

}

for _, n := range notes {

for _, tag := range n.Tags {

if _, ok := saw[tag]; !ok {

tags = append(tags, tag)

saw[tag] = struct{}{}

}

}

}

}

sort.Strings(tags)

_, err = fmt.Fprintln(cmd.Out, strings.Join(tags, "\n"))

return err

}