package server

import (
	"strings"
	"testing"

	udiff "github.com/aymanbagabas/go-udiff"

	"housecarl/internal/api"
	"housecarl/internal/model"
)

// TestBlockHeaders: each hunk says which chain it is in, even when the
// chain's own line is far above it.
func TestBlockHeaders(t *testing.T) {
	var b strings.Builder
	b.WriteString("table inet housecarl {\n\tset lan_v4 { type ipv4_addr; }\n\tchain input {\n")
	for i := 0; i < 20; i++ {
		b.WriteString("\t\tcounter comment \"in\"\n")
	}
	b.WriteString("\t}\n\tchain forward {\n")
	for i := 0; i < 20; i++ {
		b.WriteString("\t\tcounter comment \"fw\"\n")
	}
	b.WriteString("\t}\n}\n")
	now := b.String()
	then := strings.Replace(now, "\t\tcounter comment \"in\"\n\t}", "\t\tcounter comment \"in\"\n\t\taccept comment \"new in\"\n\t}", 1)
	then = strings.Replace(then, "\t\tcounter comment \"fw\"\n\t}", "\t\taccept comment \"new fw\"\n\t}", 1)

	diff := blockHeaders(udiff.Unified("a", "b", now, then), now, then)
	var heads []string
	for _, l := range strings.Split(diff, "\n") {
		if strings.HasPrefix(l, "@@") {
			heads = append(heads, l)
		}
	}
	if len(heads) != 2 || !strings.HasSuffix(heads[0], "@@ chain input") || !strings.HasSuffix(heads[1], "@@ chain forward") {
		t.Fatalf("hunk headers %q, want chain input then chain forward\n%s", heads, diff)
	}
	if blockHeaders("", now, then) != "" {
		t.Fatal("no diff should stay empty")
	}
}

// TestHistoryDiff: an entry's diff is its own change, rebuilt from the
// current configuration however many entries came after it.
func TestHistoryDiff(t *testing.T) {
	e := newEnv(t)
	var mr api.MutationResponse
	e.call(e.token, "POST", "/zones", model.Zone{Name: "lan", Interfaces: []string{"eth1"}}, nil)
	e.call(e.token, "POST", "/rules", model.Rule{Chain: "input", Match: model.Match{Services: []string{"ssh"}}, Comment: "first"}, &mr)
	first := mr.HistoryID
	e.call(e.token, "POST", "/rules", model.Rule{Chain: "forward", Match: model.Match{Services: []string{"http"}}, Comment: "second"}, nil)
	e.call(e.token, "PATCH", "/settings", map[string]any{"builtins": map[string]any{"drop_invalid": true}}, nil)

	var out struct{ Diff string }
	if code := e.call(e.token, "GET", "/history/"+itoa(first)+"/diff", nil, &out); code != 200 {
		t.Fatalf("diff: %d", code)
	}
	var added []string
	for _, l := range strings.Split(out.Diff, "\n") {
		if strings.HasPrefix(l, "+") && !strings.HasPrefix(l, "+++") {
			added = append(added, l)
		}
	}
	if len(added) == 0 || !strings.Contains(strings.Join(added, "\n"), ` first"`) || strings.Contains(out.Diff, ` second"`) || !strings.Contains(out.Diff, "@@ chain input") {
		t.Errorf("entry %d's diff:\n%s", first, out.Diff)
	}
	if code := e.call(e.token, "GET", "/history/9999/diff", nil, nil); code != 404 {
		t.Errorf("unknown entry: %d", code)
	}
}