// Copyright 2021 The Go 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 audit

import (
	"golang.org/x/tools/go/packages"
	"golang.org/x/vulndb/osv"
)

type dbClient interface {
	Get([]string) ([]*osv.Entry, error)
}

// FetchVulnerabilities fetches vulnerabilities that affect the supplied modules.
func FetchVulnerabilities(client dbClient, modules []*packages.Module) (ModuleVulnerabilities, error) {
	mv := ModuleVulnerabilities{}
	for _, mod := range modules {
		modPath := mod.Path
		modVersion := mod.Version
		if mod.Replace != nil {
			modPath = mod.Replace.Path
			modVersion = mod.Replace.Version
		}
		vulns, err := client.Get([]string{modPath})
		if err != nil {
			return nil, err
		}
		// TODO(rolandshoemaker): we may want to consider moving this functionality into
		// ModuleVulnerabilities.Filter, consolidating the filtering logic in one place.
		var filteredVulns []*osv.Entry
		for _, v := range vulns {
			if v.Affects.AffectsSemver(modVersion) {
				filteredVulns = append(filteredVulns, v)
			}
		}
		if len(filteredVulns) == 0 {
			continue
		}
		mv = append(mv, modVulns{
			mod:   mod,
			vulns: filteredVulns,
		})
	}
	return mv, nil
}