//go:build ignore
// +build ignore

package main

import (
	"encoding/json"
	"log"
	"net/http"
	"os"
	"strings"
	"text/template"
	"time"
)

// This program generates license_list.go.
const (
	source = "license_list.go"
	url    = "https://spdx.org/licenses/licenses.json"
)

var tmp = template.Must(template.New("").Parse(`// Code generated by go generate; DO NOT EDIT.
// This file was generated by robots at {{ .Timestamp }}
// using data from {{ .URL }}
package spdxlicense

const Version = {{ printf "%q" .Version }}

var licenseIDs = map[string]string{
{{- range $k, $v := .LicenseIDs }}
	{{ printf "%q" $k }}: {{ printf "%q" $v }},
{{- end }}
}
`))

type LicenseList struct {
	Version  string `json:"licenseListVersion"`
	Licenses []struct {
		ID          string   `json:"licenseId"`
		Name        string   `json:"name"`
		Text        string   `json:"licenseText"`
		Deprecated  bool     `json:"isDeprecatedLicenseId"`
		OSIApproved bool     `json:"isOsiApproved"`
		SeeAlso     []string `json:"seeAlso"`
	} `json:"licenses"`
}

func main() {
	resp, err := http.Get(url)
	if err != nil {
		log.Fatalf("unable to get licenses list: %+v", err)
	}

	var result LicenseList
	if err = json.NewDecoder(resp.Body).Decode(&result); err != nil {
		log.Fatalf("unable to decode license list: %+v", err)
	}

	f, err := os.Create(source)
	if err != nil {
		log.Fatalf("unable to create %q: %+v", source, err)
	}
	defer func() {
		if err := f.Close(); err != nil {
			log.Fatalf("unable to close %q: %+v", source, err)
		}
	}()

	var licenseIDs = make(map[string]string)
	for _, l := range result.Licenses {
		cleanID := strings.ToLower(l.ID)
		if _, exists := licenseIDs[cleanID]; exists {
			log.Fatalf("duplicate license ID found: %q", cleanID)
		}
		licenseIDs[cleanID] = l.ID
	}

	err = tmp.Execute(f, struct {
		Timestamp  time.Time
		URL        string
		Version    string
		LicenseIDs map[string]string
	}{
		Timestamp:  time.Now(),
		URL:        url,
		Version:    result.Version,
		LicenseIDs: licenseIDs,
	})

	if err != nil {
		log.Fatalf("unable to generate template: %+v", err)
	}
}