// Copyright 2023 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

// Package jiri contains jiri manifest schema definitions copied from Jiri's
// source code.
//
// Only fields relevant to roller configuration are included, others are
// omitted.
package jiri

import (
	"encoding/xml"
	"errors"
	"fmt"
	"io"
	"os"
)

type Manifest struct {
	Projects []Project `xml:"projects>project"`
	Packages []Package `xml:"packages>package"`
	XMLName  struct{}  `xml:"manifest"`
}

// Project represents a jiri project.
type Project struct {
	// Name is the project name.
	Name string `xml:"name,attr,omitempty"`

	// Remote is the project remote.
	Remote string `xml:"remote,attr,omitempty"`

	// RemoteBranch is the name of the remote branch to track.
	RemoteBranch string `xml:"remotebranch,attr,omitempty"`
}

// Package struct represents the <package> tag in manifest files.
type Package struct {
	// Name represents the remote cipd path of the package.
	Name string `xml:"name,attr"`

	// Version represents the version tag of the cipd package.
	Version string `xml:"version,attr"`
}

// LoadManifest reads a Jiri manifest from disk.
func LoadManifest(path string) (*Manifest, error) {
	b, err := os.ReadFile(path)
	if err != nil {
		return nil, err
	}
	var manifest Manifest
	if err := xml.Unmarshal(b, &manifest); err != nil {
		if errors.Is(err, io.EOF) {
			return nil, fmt.Errorf("invalid XML in %s", path)
		}
		return nil, err
	}
	return &manifest, nil
}