// Copyright 2020 the Drone Authors. All rights reserved.
// Use of this source code is governed by the Blue Oak Model License
// that can be found in the LICENSE file.

package plugin

import (
	"encoding/base64"
	"encoding/json"
	"fmt"
	"io"
	"os"
	"strings"

	"github.com/go-git/go-git/v5"
)

type GetLatestGitTagOption func(repo *git.Repository) error

var FetchTags = func(repo *git.Repository) error {
	err := repo.Fetch(&git.FetchOptions{Tags: git.AllTags})

	if err == git.NoErrAlreadyUpToDate {
		return nil
	}

	return err
}

func getLatestGitTag(options ...GetLatestGitTagOption) (tag string, err error) {
	r, err := git.PlainOpen(".")

	if err != nil {
		return "", fmt.Errorf("error opening git repo at %s: %w", ".", err)
	}

	for _, opt := range options {
		err := opt(r)
		if err != nil {
			return "", err
		}
	}

	tagRefs, err := r.Tags()

	if err != nil {
		return "", fmt.Errorf("error getting git tag refs %w", err)
	}

	for {
		r, err := tagRefs.Next()

		if err == io.EOF {
			break
		}

		if err != nil {
			return "", fmt.Errorf("error iterating tags %w", err)
		}

		parts := strings.Split(string(r.Name()), "/")
		tag = strings.Join(parts[2:], "/")
	}

	if tag == "" {
		return tag, fmt.Errorf("couldn't find any git tags")
	}

	return
}

func writeCard(path, schema string, card interface{}) {
	data, _ := json.Marshal(map[string]interface{}{
		"schema": schema,
		"data":   card,
	})
	switch {
	case path == "/dev/stdout":
		writeCardTo(os.Stdout, data)
	case path == "/dev/stderr":
		writeCardTo(os.Stderr, data)
	case path != "":
		os.WriteFile(path, data, 0644)
	}
}

func writeCardTo(out io.Writer, data []byte) {
	encoded := base64.StdEncoding.EncodeToString(data)
	io.WriteString(out, "\u001B]1338;")
	io.WriteString(out, encoded)
	io.WriteString(out, "\u001B]0m")
	io.WriteString(out, "\n")
}