// Copyright 2019 Yunion
//
// 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 promputils

import (
	"io/ioutil"
	"log"
	"path/filepath"
	"strings"

	prompt "github.com/c-bata/go-prompt"
)

func init() {
	fileListCache = map[string][]prompt.Suggest{}
}

func getPreviousOption(d prompt.Document) (cmd, option string, found bool) {
	args := strings.Split(d.TextBeforeCursor(), " ")
	l := len(args)
	if l >= 2 {
		option = args[l-2]
	}
	if strings.HasPrefix(option, "-") {
		return args[0], option, true
	}
	return "", "", false
}

func completeOptionArguments(d prompt.Document) ([]prompt.Suggest, bool) {
	cmd, option, found := getPreviousOption(d)
	if !found {
		return []prompt.Suggest{}, false
	}
	switch cmd {
	case "server-attach-disk", "describe", "create", "delete", "replace", "patch",
		"edit", "apply", "expose", "rolling-update", "rollout",
		"label", "annotate", "scale", "convert", "autoscale":
		switch option {
		case "-f", "--filename":
			return fileCompleter(d), true
		}
	}
	return []prompt.Suggest{}, false
}

/* file list */

var fileListCache map[string][]prompt.Suggest

func fileCompleter(d prompt.Document) []prompt.Suggest {
	path := d.GetWordBeforeCursor()
	if strings.HasPrefix(path, "./") {
		path = path[2:]
	}
	dir := filepath.Dir(path)
	if cached, ok := fileListCache[dir]; ok {
		return cached
	}

	files, err := ioutil.ReadDir(dir)
	if err != nil {
		log.Print("[ERROR] catch error " + err.Error())
		return []prompt.Suggest{}
	}
	suggests := make([]prompt.Suggest, 0, len(files))
	for _, f := range files {
		if !f.IsDir() &&
			!strings.HasSuffix(f.Name(), ".yml") &&
			!strings.HasSuffix(f.Name(), ".yaml") {
			continue
		}
		suggests = append(suggests, prompt.Suggest{Text: filepath.Join(dir, f.Name())})
	}
	return prompt.FilterHasPrefix(suggests, path, false)
}