// Command fakejarl answers the part of Jarl's API that Housecarl's Jarl
// sets read (GET /zones, GET /zones/{id}/records), from a JSON file read
// again on each request, so the e2e test can change records:
//
//	{"zones": [{"id": 1, "name": "example.com.", "view": "internal", "type": "primary"}],
//	 "records": {"1": [{"name": "nas.example.com.", "type": "A", "data": "10.0.0.5"}]}}
//
// Usage: fakejarl -listen 127.0.0.1:8053 -data jarl.json -token SECRET
package main

import (
	"encoding/json"
	"flag"
	"log"
	"net/http"
	"os"
	"strings"
)

type data struct {
	Zones   []map[string]any            `json:"zones"`
	Records map[string][]map[string]any `json:"records"`
}

func main() {
	listen := flag.String("listen", "127.0.0.1:8053", "address to listen on")
	file := flag.String("data", "jarl.json", "the zones and records")
	token := flag.String("token", "", "the API token Housecarl must send")
	flag.Parse()
	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
		if r.Header.Get("Authorization") != "Bearer "+*token {
			w.WriteHeader(http.StatusUnauthorized)
			w.Write([]byte(`{"error": {"code": "unauthorized", "message": "bad token"}}`))
			return
		}
		b, err := os.ReadFile(*file)
		var d data
		if err == nil {
			err = json.Unmarshal(b, &d)
		}
		if err != nil {
			http.Error(w, err.Error(), http.StatusInternalServerError)
			return
		}
		w.Header().Set("Content-Type", "application/json")
		p := strings.TrimPrefix(r.URL.Path, "/api/v1")
		switch {
		case p == "/zones":
			json.NewEncoder(w).Encode(d.Zones)
		case strings.HasPrefix(p, "/zones/") && strings.HasSuffix(p, "/records"):
			id := strings.TrimSuffix(strings.TrimPrefix(p, "/zones/"), "/records")
			recs := d.Records[id]
			if recs == nil {
				recs = []map[string]any{}
			}
			json.NewEncoder(w).Encode(recs)
		default:
			w.WriteHeader(http.StatusNotFound)
			w.Write([]byte(`{"error": {"code": "not_found", "message": "not found"}}`))
		}
	})
	log.Fatal(http.ListenAndServe(*listen, nil))
}