feat: mediocre WholeScreenCapturer implementation

2025-11-25 14:31:00 +03:00
parent 419dc56f50
commit 4a39c1e157
6 changed files with 240 additions and 23 deletions
--- a/src/cmd/main.go
+++ b/src/cmd/main.go
@@ -23,6 +23,7 @@ import (
 	"git.weirdcat.su/weirdcat/auto-attendance/internal/config"
 	"git.weirdcat.su/weirdcat/auto-attendance/internal/linkvalidator"
 	"git.weirdcat.su/weirdcat/auto-attendance/internal/logger"
+	"git.weirdcat.su/weirdcat/auto-attendance/internal/screencapturer"
 	"go.uber.org/fx"
 )

@@ -32,9 +33,10 @@ func main() {
 			config.NewConfig,
 			logger.NewLogger,
 			linkvalidator.NewLinkValidator,
+			screencapturer.NewWholeScreenCapturer,
 		),
-		fx.Invoke(func(log *logger.Logger) {
-			log.Info("Starting application...");
+		fx.Invoke(func(log *logger.Logger, capturer screencapturer.ScreenCapturer) {
+			log.Debug("starting application...")
 		}),
 	)

--- a/src/go.mod
+++ b/src/go.mod
@@ -6,7 +6,12 @@ require github.com/spf13/viper v1.21.0

 require (
 	github.com/fsnotify/fsnotify v1.9.0 // indirect
+	github.com/gen2brain/shm v0.1.0 // indirect
 	github.com/go-viper/mapstructure/v2 v2.4.0 // indirect
+	github.com/godbus/dbus/v5 v5.1.0 // indirect
+	github.com/jezek/xgb v1.1.1 // indirect
+	github.com/kbinani/screenshot v0.0.0-20250624051815-089614a94018 // indirect
+	github.com/lxn/win v0.0.0-20210218163916-a377121e959e // indirect
 	github.com/pelletier/go-toml/v2 v2.2.4 // indirect
 	github.com/sagikazarmark/locafero v0.11.0 // indirect
 	github.com/sourcegraph/conc v0.3.1-0.20240121214520-5f936abd7ae8 // indirect
--- a/src/go.sum
+++ b/src/go.sum
@@ -1,7 +1,17 @@
 github.com/fsnotify/fsnotify v1.9.0 h1:2Ml+OJNzbYCTzsxtv8vKSFD9PbJjmhYF14k/jKC7S9k=
 github.com/fsnotify/fsnotify v1.9.0/go.mod h1:8jBTzvmWwFyi3Pb8djgCCO5IBqzKJ/Jwo8TRcHyHii0=
+github.com/gen2brain/shm v0.1.0 h1:MwPeg+zJQXN0RM9o+HqaSFypNoNEcNpeoGp0BTSx2YY=
+github.com/gen2brain/shm v0.1.0/go.mod h1:UgIcVtvmOu+aCJpqJX7GOtiN7X2ct+TKLg4RTxwPIUA=
 github.com/go-viper/mapstructure/v2 v2.4.0 h1:EBsztssimR/CONLSZZ04E8qAkxNYq4Qp9LvH92wZUgs=
 github.com/go-viper/mapstructure/v2 v2.4.0/go.mod h1:oJDH3BJKyqBA2TXFhDsKDGDTlndYOZ6rGS0BRZIxGhM=
+github.com/godbus/dbus/v5 v5.1.0 h1:4KLkAxT3aOY8Li4FRJe/KvhoNFFxo0m6fNuFUO8QJUk=
+github.com/godbus/dbus/v5 v5.1.0/go.mod h1:xhWf0FNVPg57R7Z0UbKHbJfkEywrmjJnf7w5xrFpKfA=
+github.com/jezek/xgb v1.1.1 h1:bE/r8ZZtSv7l9gk6nU0mYx51aXrvnyb44892TwSaqS4=
+github.com/jezek/xgb v1.1.1/go.mod h1:nrhwO0FX/enq75I7Y7G8iN1ubpSGZEiA3v9e9GyRFlk=
+github.com/kbinani/screenshot v0.0.0-20250624051815-089614a94018 h1:NQYgMY188uWrS+E/7xMVpydsI48PMHcc7SfR4OxkDF4=
+github.com/kbinani/screenshot v0.0.0-20250624051815-089614a94018/go.mod h1:Pmpz2BLf55auQZ67u3rvyI2vAQvNetkK/4zYUmpauZQ=
+github.com/lxn/win v0.0.0-20210218163916-a377121e959e h1:H+t6A/QJMbhCSEH5rAuRxh+CtW96g0Or0Fxa9IKr4uc=
+github.com/lxn/win v0.0.0-20210218163916-a377121e959e/go.mod h1:KxxjdtRkfNoYDCUP5ryK7XJJNTnpC8atvtmTheChOtk=
 github.com/pelletier/go-toml/v2 v2.2.4 h1:mye9XuhQ6gvn5h28+VilKrrPoQVanw5PMw/TB0t5Ec4=
 github.com/pelletier/go-toml/v2 v2.2.4/go.mod h1:2gIqNv+qfxSVS7cM2xJQKtLSTLUE9V8t9Stt+h56mCY=
 github.com/sagikazarmark/locafero v0.11.0 h1:1iurJgmM9G3PA/I+wWYIOw/5SyBtxapeHDcg+AAIFXc=
@@ -28,6 +38,7 @@ go.uber.org/zap v1.26.0 h1:sI7k6L95XOKS281NhVKOFCUNIvv9e0w4BF8N3u+tCRo=
 go.uber.org/zap v1.26.0/go.mod h1:dtElttAiwGvoJ/vj4IwHBS/gXsEu/pZ50mUIRWuG0so=
 go.yaml.in/yaml/v3 v3.0.4 h1:tfq32ie2Jv2UxXFdLJdh3jXuOzWiL1fo0bu/FbuKpbc=
 go.yaml.in/yaml/v3 v3.0.4/go.mod h1:DhzuOOF2ATzADvBadXxruRBLzYTpT36CKvDb3+aBEFg=
+golang.org/x/sys v0.0.0-20201018230417-eeed37f84f13/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.29.0 h1:TPYlXGxvx1MGTn2GiZDhnjPA9wZzZeGKHHmKhHYvgaU=
 golang.org/x/sys v0.29.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
 golang.org/x/text v0.28.0 h1:rhazDwis8INMIwQ4tpjLDzUhx6RlXqZNPEM0huQojng=
--- a/src/internal/screencapturer/interface.go
+++ b/src/internal/screencapturer/interface.go
@@ -20,7 +20,8 @@
 package screencapturer

 type ScreenCapturer interface {
+	Init() error
 	Start() error
 	Stop() error
-	Screenshot() (filepath string)
+	Get() (filepath string, err error)
 }
--- a/src/internal/screencapturer/wholescreencapturer.go
+++ b/src/internal/screencapturer/wholescreencapturer.go
@@ -0,0 +1,218 @@
+// Copyright (c) 2025 Nikolai Papin
+//
+// This file is part of the Auto Attendance app that looks for
+// self-attend QR-codes during lectures and opens their URLs in your
+// browser.
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
+// the GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+package screencapturer
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"image"
+	"image/png"
+	"os"
+	"path/filepath"
+	"sync"
+	"time"
+
+	"git.weirdcat.su/weirdcat/auto-attendance/internal/config"
+	"git.weirdcat.su/weirdcat/auto-attendance/internal/constants"
+	"git.weirdcat.su/weirdcat/auto-attendance/internal/logger"
+	"github.com/kbinani/screenshot"
+	"go.uber.org/fx"
+)
+
+var (
+	ErrNotInitialized = errors.New("wholescreencapturer was not initialized")
+)
+
+type wholeScreenCapturer struct {
+	config *config.Config
+	log *logger.Logger
+
+	displayIndex int
+	displayBounds image.Rectangle 
+	interval int
+	bufferCount int
+	tempDirectory string
+	initialized bool
+	running bool
+
+	files  []string
+	latest string
+	done   chan struct{}
+	sync.WaitGroup
+}
+
+// Get implements ScreenCapturer.
+func (w *wholeScreenCapturer) Get() (filepath string, err error) {
+	if !w.initialized {
+		return "", ErrNotInitialized
+	}
+	if w.latest == "" {
+		return "", errors.New("no screenshot captured yet")
+	}
+	return w.latest, nil
+}
+
+// Init implements ScreenCapturer.
+func (w *wholeScreenCapturer) Init() (err error) {
+
+	displayCount := screenshot.NumActiveDisplays()
+	w.displayIndex = w.config.Screenshot.ScreenIndex % displayCount
+	w.log.Debug("detected displays", "count", displayCount, "selected", w.displayIndex)
+
+	w.displayBounds = screenshot.GetDisplayBounds(w.displayIndex)
+	w.log.Debug(
+		"display bounds set",
+		"dx", w.displayBounds.Dx(),
+		"dy", w.displayBounds.Dy(),
+	)
+
+	w.interval = w.config.Screenshot.Interval
+	w.log.Debug("screenshot interval set", "interval", w.interval)
+
+	w.bufferCount = w.config.Screenshot.BufferCount
+	w.log.Debug("screenshot buffer count set", "count", w.bufferCount)
+
+	if w.tempDirectory, err = w.createTempDirectory(); err != nil {
+		w.log.Error("failed to create temporary directory", "error", err)
+		return err
+	}
+	w.log.Debug("temporary directory created", "path", w.tempDirectory)
+
+	w.files = make([]string, 0, w.bufferCount)
+	w.latest = ""
+	w.initialized = true
+	return nil
+}
+
+// Start implements ScreenCapturer.
+func (w *wholeScreenCapturer) Start() error {
+	if !w.initialized {
+		return ErrNotInitialized
+	}
+	if w.running {
+		w.log.Debug("wholescreencapturer is already running, ignoring start")
+		return nil
+	}
+	w.running = true
+	w.Go(func() {
+		w.captureLoop()
+	})
+	w.log.Debug("wholescreencapturer started")
+	return nil
+}
+
+// Stop implements ScreenCapturer.
+func (w *wholeScreenCapturer) Stop() error {
+	if !w.initialized {
+		return ErrNotInitialized
+	}
+	if !w.running {
+		w.log.Debug("wholescreencapturer is not running, ignoring stop")
+		return nil
+	}
+	w.log.Debug("stopping wholescreencapturer")
+	close(w.done)
+	w.Wait()
+	w.running = false
+	w.log.Debug("wholescreencapturer stopped")
+	return nil
+}
+
+func (w *wholeScreenCapturer) captureLoop() {
+	ticker := time.NewTicker(time.Duration(w.interval) * time.Second)
+	defer ticker.Stop()
+
+	for {
+		select {
+		case <-w.done:
+			w.log.Debug("capture loop stopped")
+			return
+		case <-ticker.C:
+			fp, err := w.captureAndSave()
+			if err != nil {
+				w.log.Error("screenshot capture failed", "error", err)
+				continue
+			}
+			w.addToBuffer(fp)
+		}
+	}
+}
+
+func (w *wholeScreenCapturer) captureAndSave() (string, error) {
+	img, err := screenshot.CaptureRect(w.displayBounds)
+	if err != nil {
+		w.log.Error("failed to capture screenshot", "error", err)
+		return "", err
+	}
+
+	now := time.Now().UnixMilli()
+	filename := fmt.Sprintf("%d.png", now)
+	filePath := filepath.Join(w.tempDirectory, filename)
+
+	file, err := os.Create(filePath)
+	if err != nil {
+		w.log.Error("failed to create screenshot file", "path", filePath, "error", err)
+		return "", err
+	}
+
+	defer file.Close()
+	err = png.Encode(file, img)
+	if err != nil {
+		w.log.Error("failed to encode image into file", "path", filePath, "error", err)
+		return "", err
+	}
+
+	w.log.Debug("Screenshot saved", "path", filePath)
+	return filePath, nil
+}
+
+func (w *wholeScreenCapturer) addToBuffer(fp string) {
+	w.files = append(w.files, fp)
+	w.latest = fp
+
+	if len(w.files) > w.bufferCount {
+		old := w.files[0]
+		if err := os.Remove(old); err != nil {
+			w.log.Warn("failed to remove old screenshot", "path", old, "error", err)
+		} else {
+			w.log.Debug("removed old screenshot", "path", old)
+		}
+		w.files = w.files[1:]
+	}
+}
+
+func (w *wholeScreenCapturer) createTempDirectory() (path string, err error) {
+	return os.MkdirTemp(w.config.Screenshot.Directory, constants.AppName+"-*")
+}
+
+func NewWholeScreenCapturer(lc fx.Lifecycle, config *config.Config, log *logger.Logger) ScreenCapturer {
+	capturer := &wholeScreenCapturer{
+		config: config,
+		log:    log,
+		done:   make(chan struct{}),
+	}
+	lc.Append(fx.StopHook(func(ctx context.Context) error {
+		log.Debug("Stopping capturer (fx hook)")
+		return capturer.Stop()
+	}))
+	return capturer
+}
+
--- a/src/internal/screenshotter/screenshotter.go
+++ b/src/internal/screenshotter/screenshotter.go
@@ -1,20 +0,0 @@
-// Copyright (c) 2025 Nikolai Papin
-//
-// This file is part of the Auto Attendance app that looks for
-// self-attend QR-codes during lectures and opens their URLs in your 
-// browser.
-//
-// This program is free software: you can redistribute it and/or modify
-// it under the terms of the GNU General Public License as published by
-// the Free Software Foundation, either version 3 of the License, or
-// (at your option) any later version.
-//
-// This program is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
-// the GNU General Public License for more details.
-//
-// You should have received a copy of the GNU General Public License
-// along with this program.  If not, see <https://www.gnu.org/licenses/>.
-
-package screenshotter