// Copyright (c) 2026 Storm Dragon
// Authors: Storm Dragon, Angus Kola
// SPDX-License-Identifier: GPL-3.0-or-later

package atspi

import (
	"bufio"
	"bytes"
	"context"
	"encoding/json"
	"fmt"
	"log/slog"
	"os"
	"os/exec"
	"path/filepath"
	"strings"
	"testing"
	"time"
	"unicode/utf8"

	"git.stormux.org/storm/cthulhu/internal/logging"
)

func TestNativeFlatReviewPreservesProviderCache(t *testing.T) {
	if os.Getenv("CTHULHU_NATIVE_REVIEW_CACHE") != "1" {
		t.Skip("requires private Xvfb/AT-SPI session")
	}
	test_native_review_provider(t, "cache")
}

func TestNativeFlatReviewBoundsSlowLongRanges(t *testing.T) {
	if os.Getenv("CTHULHU_NATIVE_REVIEW_BOUNDS") != "1" {
		t.Skip("requires private Xvfb/AT-SPI session")
	}
	test_native_review_provider(t, "bounds")
}

func TestNativeFlatReviewClippedViewport(t *testing.T) {
	if os.Getenv("CTHULHU_NATIVE_REVIEW_CLIPPED") != "1" {
		t.Skip("requires private Xvfb/AT-SPI session")
	}
	test_native_review_provider(t, "clipped")
}

func TestNativeFlatReviewLargeTextViewport(t *testing.T) {
	if os.Getenv("CTHULHU_NATIVE_REVIEW_VIEWPORT") != "1" {
		t.Skip("requires private Xvfb/AT-SPI session")
	}
	// Adapter ownership is process-global; each mode runs in its own process.
	mode := os.Getenv("CTHULHU_NATIVE_REVIEW_VIEWPORT_MODE")
	if mode != "lines" && mode != "long" {
		t.Fatal("set viewport mode to lines or long")
	}
	test_native_review_provider(t, mode)
}

func TestNativeFlatReviewUnavailableSubtree(t *testing.T) {
	if os.Getenv("CTHULHU_NATIVE_REVIEW_SUBTREE") != "1" {
		t.Skip("requires private Xvfb/AT-SPI session")
	}
	test_native_review_provider(t, "children")
}

func TestNativeFlatReviewZeroAreaGlyph(t *testing.T) {
	if os.Getenv("CTHULHU_NATIVE_REVIEW_GLYPHS") != "1" {
		t.Skip("requires private Xvfb/AT-SPI session")
	}
	test_native_review_provider(t, "glyphs")
}

func test_native_review_provider(t *testing.T, mode string) {
	t.Helper()
	ctx, cancel := context.WithTimeout(context.Background(), 20*time.Second)
	defer cancel()
	flags, err := exec.CommandContext(ctx, "pkg-config", "--cflags", "--libs", "gtk+-3.0").Output()
	if err != nil {
		t.Fatal(err)
	}
	binary := filepath.Join(t.TempDir(), "review-cache-fixture")
	args := append([]string{"../../tests/review_cache_fixture.c", "-o", binary}, strings.Fields(string(flags))...)
	if output, err := exec.CommandContext(ctx, "cc", args...).CombinedOutput(); err != nil {
		t.Fatalf("build fixture: %v: %s", err, output)
	}
	var diagnostics bytes.Buffer
	adapter := New()
	adapter.SetCaptureLogger(logging.New(&diagnostics, logging.Options{Level: slog.LevelDebug}))
	if err := adapter.Start(ctx); err != nil {
		t.Fatal(err)
	}
	defer adapter.Stop(context.Background())
	fixture := exec.CommandContext(ctx, binary, mode)
	fixture.Stderr = os.Stderr
	input, err := fixture.StdinPipe()
	if err != nil {
		t.Fatal(err)
	}
	output, err := fixture.StdoutPipe()
	if err != nil {
		t.Fatal(err)
	}
	if err := fixture.Start(); err != nil {
		t.Fatal(err)
	}
	defer func() {
		_ = fixture.Process.Kill()
		_ = fixture.Wait()
	}()
	if output, err := exec.CommandContext(ctx, "xdotool", "search", "--sync", "--onlyvisible", "--name", "^Review cache probe$", "windowfocus").CombinedOutput(); err != nil {
		t.Fatalf("focus fixture: %v: %s", err, output)
	}
	var focus ObjectID
	for !focus.Valid() {
		select {
		case event := <-adapter.Events():
			if event.Type == WindowActivatedEvent && event.WindowTitle == "Review cache probe" {
				focus = event.Source.ID()
			}
		case <-ctx.Done():
			t.Fatal("fixture focus missing")
		}
	}
	scanner := bufio.NewScanner(output)
	command := func(request, want string) {
		t.Helper()
		if _, err := fmt.Fprintln(input, request); err != nil {
			t.Fatal(err)
		}
		if !scanner.Scan() || scanner.Text() != want {
			t.Fatalf("fixture %s: %q, %v", request, scanner.Text(), scanner.Err())
		}
	}
	if mode == "bounds" || mode == "clipped" || mode == "long" || mode == "lines" || mode == "glyphs" {
		command("measure", "measuring")
	} else if mode != "children" {
		command("arm", "armed")
	}
	if mode == "lines" {
		command("scroll", "scrolled")
	}
	tree, err := adapter.CaptureReviewWindow(ctx, focus)
	if err != nil {
		t.Fatal(err)
	}
	var timing struct {
		Message       string               `json:"message"`
		RootScope     string               `json:"root_scope"`
		CapturedNodes int                  `json:"captured_nodes"`
		Stages        []captureStageTiming `json:"stages"`
	}
	if err := json.Unmarshal(diagnostics.Bytes(), &timing); err != nil {
		t.Fatalf("capture diagnostics: %v: %s", err, diagnostics.Bytes())
	}
	if timing.Message != "flat review capture timing" || timing.RootScope != "window" || timing.CapturedNodes == 0 {
		t.Fatalf("missing capture scope/progress: %+v", timing)
	}
	if mode == "children" {
		broken := findNamedReference(t, tree, "Broken subtree")
		if !broken.Valid() {
			t.Fatal("broken subtree fixture missing")
		}
		command("arm", "armed")
		tree.InvalidateChildren(broken.ID())
		tree, err = adapter.CaptureReviewWindow(ctx, focus)
		if err != nil {
			t.Fatal(err)
		}
		snapshot, err := tree.ReviewWindow(ctx, focus)
		if err != nil {
			t.Fatal(err)
		}
		omitted, healthy := false, false
		for _, node := range snapshot.Nodes {
			omitted = omitted || node.Snapshot.ID() == broken.ID() && node.ChildrenUnavailable
			for _, span := range node.Text.Ranges {
				healthy = healthy || span.Text == "Cached review text"
			}
		}
		if !omitted || !healthy {
			t.Fatalf("subtree recovery: omission=%v healthy=%v", omitted, healthy)
		}
		return
	}
	for _, want := range []string{"queue-wait", "root-selection", "snapshot", "geometry", "visible-text", "table-viewport", "child-count", "child-enumeration", "tree-installation"} {
		found := false
		for _, stage := range timing.Stages {
			if stage.Stage == want && stage.Calls > 0 && stage.Duration > 0 {
				found = true
			}
		}
		if !found {
			t.Errorf("capture timing missing stage %q: %+v", want, timing)
		}
	}
	if mode == "bounds" || mode == "clipped" || mode == "long" || mode == "lines" || mode == "glyphs" {
		label := findNamedReference(t, tree, "Long review label")
		if !label.Valid() {
			t.Fatal("long label missing from review")
		}
		text, err := tree.VisibleText(label)
		if err != nil || !text.Known || text.Limited || len(text.Ranges) == 0 {
			t.Fatalf("long label text: %+v, %v", text, err)
		}
		if mode == "bounds" {
			command("largest", "largest 128")
			command("repeated", "repeated 0")
		}
		if mode == "lines" && text.Ranges[0].Start <= maxReviewCharacters {
			t.Fatalf("line viewport did not seek scrolled native offsets: %d", text.Ranges[0].Start)
		}
		if mode == "glyphs" {
			for _, span := range text.Ranges {
				if span.Start <= 5 && span.End > 5 {
					t.Fatalf("zero-area glyph included as visible text: %+v", span)
				}
			}
		}
		if mode == "clipped" {
			characters := 0
			for _, span := range text.Ranges {
				characters += utf8.RuneCountInString(span.Text)
			}
			if characters <= maxReviewRanges || len(text.Ranges) > 21 {
				t.Fatalf("fixture must capture hundreds of characters as visual spans: characters=%d ranges=%d", characters, len(text.Ranges))
			}
		}
		return
	}
	label := findNamedReference(t, tree, "Cached review text")
	if !label.Valid() {
		t.Fatal("cached label missing from review")
	}
	command("count", "count 0")
	command("change", "changed")
	for {
		select {
		case event := <-adapter.Events():
			if event.Source.ID() == label.ID() && strings.HasPrefix(event.Type, "object:text-changed:") {
				goto changed
			}
		case <-ctx.Done():
			t.Fatal("text change missing")
		}
	}
changed:
	tree, err = adapter.CaptureReviewWindow(ctx, focus)
	if err != nil {
		t.Fatal(err)
	}
	if !findNamedReference(t, tree, "Changed review text").Valid() {
		t.Fatal("dirty label retained old provider data")
	}
}