package geo

import (
	"encoding/json"
	"os"
	"regexp"
	"strings"
	"testing"
)

func TestAWSRegionTable(t *testing.T) {
	shape := regexp.MustCompile(`^[a-z]{2}(-[a-z]+)+-\d$`)
	for code, r := range awsRegions {
		if !shape.MatchString(code) {
			t.Errorf("%s is not an AWS region code", code)
		}
		if r.Lat < -90 || r.Lat > 90 || r.Lon < -180 || r.Lon > 180 {
			t.Errorf("%s: %v out of range", code, r.Point)
		}
		if r.Place == "" || strings.Contains(r.Place, "—") {
			t.Errorf("%s: place %q empty or contains an em dash", code, r.Place)
		}
	}
	if len(awsRegions) != 34 {
		t.Errorf("%d regions, want the 34 of spec C23", len(awsRegions))
	}
	if PlaceName("xx-nowhere-1", "zz") != "zz" || PlaceName("", "ie") != "ie" {
		t.Error("PlaceName must fall back to the given code")
	}
	if r, ok := LookupAWSRegion("eu-west-2"); !ok || PlaceName("eu-west-2", "uk") != r.Place {
		t.Error("PlaceName must read the table")
	}
}

func TestNearestUsesTheTable(t *testing.T) {
	london, _ := ZonePoint("Europe/London")
	got, ok := Nearest(london, []Candidate{
		{Code: "", Home: true, AWSRegion: "eu-west-1"},
		{Code: "uk", AWSRegion: "eu-west-2"},
	})
	if !ok || got != "uk" {
		t.Fatalf("Nearest from London = (%q, %v), want uk", got, ok)
	}
}

// TestPlaceNamesMatchApprovedRecord fails if any C23-* text in the approved
// copy record is missing from awsregions.go as a whole quoted Go string
// literal, or differs from the table's place for that region.
func TestPlaceNamesMatchApprovedRecord(t *testing.T) {
	raw, err := os.ReadFile("../../docs/superpowers/plans/2026-10-02-nearest-region-copy.json")
	if err != nil {
		t.Fatal(err)
	}
	var rec struct {
		Entries []struct {
			ID   string `json:"id"`
			Text string `json:"text"`
		} `json:"entries"`
	}
	if err := json.Unmarshal(raw, &rec); err != nil {
		t.Fatal(err)
	}
	src, err := os.ReadFile("awsregions.go")
	if err != nil {
		t.Fatal(err)
	}
	seen := map[string]bool{}
	for _, e := range rec.Entries {
		code, ok := strings.CutPrefix(e.ID, "C23-")
		if !ok {
			continue
		}
		seen[code] = true
		if e.Text == "" {
			t.Errorf("%s: empty text in the record", e.ID)
			continue
		}
		if !strings.Contains(string(src), `"`+e.Text+`"`) {
			t.Errorf("%s: %q is not a quoted string literal in awsregions.go", e.ID, e.Text)
		}
		if r, ok := LookupAWSRegion(code); !ok {
			t.Errorf("%s: region missing from the table", e.ID)
		} else if r.Place != e.Text {
			t.Errorf("%s: table place %q, record %q", e.ID, r.Place, e.Text)
		}
	}
	for code := range awsRegions {
		if !seen[code] {
			t.Errorf("%s: in the table but has no C23 entry in the record", code)
		}
	}
	if len(seen) != 34 {
		t.Errorf("%d C23 entries in the record, want 34", len(seen))
	}
}