package workflow

import (
	"fmt"
	"io"
	"strings"

	"github.com/valyala/fasttemplate"
)

type Step struct {
	Name  string `yaml:"name"`
	Run   string `yaml:"run"`
	Shell string `yaml:"shell"`
}

func (s Step) RenderCommand(c Context) string {
	return fasttemplate.ExecuteFuncString(s.Run, "{{", "}}", func(w io.Writer, tag string) (int, error) {
		switch tag {
		case "torrent_name":
			return fmt.Fprintf(w, "%q", c.TorrentName)
		case "!torrent_name":
			return io.WriteString(w, c.TorrentName)
		case "category":
			return fmt.Fprintf(w, "%q", c.Category)
		case "!category":
			return io.WriteString(w, c.Category)
		case "tags":
			return fmt.Fprintf(w, "%q", strings.Join(c.Tags, ","))
		case "!tags":
			return io.WriteString(w, strings.Join(c.Tags, ","))
		default:
			if strings.HasPrefix(tag, "tags[") {
				var index int
				if n, _ := fmt.Sscanf(tag, "tags[%d]", &index); n > 0 {
					if len(c.Tags) > index {
						return fmt.Fprintf(w, "%q", c.Tags[index])
					}
				}
			}
			if strings.HasPrefix(tag, "!tags[") {
				var index int
				if n, _ := fmt.Sscanf(tag, "!tags[%d]", &index); n > 0 {
					if len(c.Tags) > index {
						return io.WriteString(w, c.Tags[index])
					}
				}
			}
			return 0, nil
		}
	})
}