package datekeys_test

import (
	"errors"
	"fmt"
	"os"
	"strings"
	"testing"

	datekeys "g.activething.com/go/DateKeys"
)

// The catalogue matches spec §69 exactly, in order.
func TestCatalogueMatchesSpec(t *testing.T) {
	spec, err := os.ReadFile("spec/DateKeys_Protocol_Specification_v" + datekeys.SpecVersion + ".md")
	if err != nil {
		t.Fatal(err)
	}
	s := string(spec)
	start := strings.Index(s, "## 69. Errores normativos")
	end := strings.Index(s, "## 70.")
	if start < 0 || end < start {
		t.Fatal("section 69 not found")
	}
	var want []string
	for _, line := range strings.Split(s[start:end], "\n") {
		if line = strings.TrimSpace(line); strings.HasPrefix(line, "ERR_") {
			want = append(want, line)
		}
	}
	var got []string
	for _, e := range datekeys.All() {
		got = append(got, e.Code())
	}
	if strings.Join(got, ",") != strings.Join(want, ",") {
		t.Fatalf("catalogue\n got %v\nwant %v", got, want)
	}
}

func TestCode(t *testing.T) {
	err := fmt.Errorf("capsule: step 8: %w", fmt.Errorf("agewrap: %w", datekeys.ErrRoundMismatch))
	if datekeys.Code(err) != "ERR_ROUND_MISMATCH" || !errors.Is(err, datekeys.ErrRoundMismatch) || errors.Is(err, datekeys.ErrIntegrity) {
		t.Fatal("wrapping")
	}
	// The failure of a relay kept as text, as provider/drand.Client keeps
	// it, adds no code: the error wraps exactly one normative error.
	relays := fmt.Errorf("drand: no relay returned a verified release for round 1000: %v: %w",
		fmt.Errorf("relay: %w", datekeys.ErrRoundMismatch), datekeys.ErrReleaseUnavailable)
	if datekeys.Code(relays) != "ERR_RELEASE_UNAVAILABLE" || errors.Is(relays, datekeys.ErrRoundMismatch) || !strings.Contains(relays.Error(), "ERR_ROUND_MISMATCH") {
		t.Fatal("a failure kept as text")
	}
	// No error of this module wraps two codes. For one from elsewhere, such
	// as the error of a caller's release source, Code returns the first in
	// the tree.
	joined := fmt.Errorf("source: %w: %w", datekeys.ErrReleaseUnavailable, errors.Join(errors.New("x"), datekeys.ErrReleaseInvalid))
	if datekeys.Code(joined) != "ERR_RELEASE_UNAVAILABLE" {
		t.Fatal("joined errors")
	}
	if datekeys.Code(errors.New("plain")) != "" || datekeys.Code(nil) != "" {
		t.Fatal("non-DateKeys errors have no code")
	}
	if datekeys.ErrIntegrity.Error() != "ERR_INTEGRITY" {
		t.Fatal("message")
	}
	data := fmt.Errorf("capsule: step 4: %w", datekeys.ErrExtensionDataInvalid)
	if datekeys.Code(data) != "ERR_EXTENSION_DATA_INVALID" || errors.Is(data, datekeys.ErrExtensionCriticalUnknown) {
		t.Fatal("ERR_EXTENSION_DATA_INVALID")
	}
}