refactor(core)!: Add context, config, and structured logging

Introduces `context.Context` to the `FetchCourse` method and its call chain, allowing for cancellable network requests and timeouts. This improves application robustness when fetching remote course data.

A new configuration package centralizes application settings, loading them from environment variables with sensible defaults for base URL, request timeout, and logging.

Standard `log` and `fmt` calls are replaced with a structured logging system built on `slog`, supporting both JSON and human-readable text formats.

This change also includes:
- Extensive benchmarks and example tests.
- Simplified Go doc comments across several packages.

BREAKING CHANGE: The `NewArticulateParser` constructor signature has been updated to accept a logger, base URL, and timeout, which are now supplied via the new configuration system.

internal/config/config.go

@@ -0,0 +1,77 @@
+// Package config provides configuration management for the articulate-parser application.
+// It supports loading configuration from environment variables and command-line flags.
+package config
+
+import (
+	"log/slog"
+	"os"
+	"strconv"
+	"time"
+)
+
+// Config holds all configuration values for the application.
+type Config struct {
+	// Parser configuration
+	BaseURL        string
+	RequestTimeout time.Duration
+
+	// Logging configuration
+	LogLevel  slog.Level
+	LogFormat string // "json" or "text"
+}
+
+// Default configuration values.
+const (
+	DefaultBaseURL        = "https://rise.articulate.com"
+	DefaultRequestTimeout = 30 * time.Second
+	DefaultLogLevel       = slog.LevelInfo
+	DefaultLogFormat      = "text"
+)
+
+// Load creates a new Config with values from environment variables.
+// Falls back to defaults if environment variables are not set.
+func Load() *Config {
+	return &Config{
+		BaseURL:        getEnv("ARTICULATE_BASE_URL", DefaultBaseURL),
+		RequestTimeout: getDurationEnv("ARTICULATE_REQUEST_TIMEOUT", DefaultRequestTimeout),
+		LogLevel:       getLogLevelEnv("LOG_LEVEL", DefaultLogLevel),
+		LogFormat:      getEnv("LOG_FORMAT", DefaultLogFormat),
+	}
+}
+
+// getEnv retrieves an environment variable or returns the default value.
+func getEnv(key, defaultValue string) string {
+	if value := os.Getenv(key); value != "" {
+		return value
+	}
+	return defaultValue
+}
+
+// getDurationEnv retrieves a duration from environment variable or returns default.
+// The environment variable should be in seconds (e.g., "30" for 30 seconds).
+func getDurationEnv(key string, defaultValue time.Duration) time.Duration {
+	if value := os.Getenv(key); value != "" {
+		if seconds, err := strconv.Atoi(value); err == nil {
+			return time.Duration(seconds) * time.Second
+		}
+	}
+	return defaultValue
+}
+
+// getLogLevelEnv retrieves a log level from environment variable or returns default.
+// Accepts: "debug", "info", "warn", "error" (case-insensitive).
+func getLogLevelEnv(key string, defaultValue slog.Level) slog.Level {
+	value := os.Getenv(key)
+	switch value {
+	case "debug", "DEBUG":
+		return slog.LevelDebug
+	case "info", "INFO":
+		return slog.LevelInfo
+	case "warn", "WARN", "warning", "WARNING":
+		return slog.LevelWarn
+	case "error", "ERROR":
+		return slog.LevelError
+	default:
+		return defaultValue
+	}
+}

internal/config/config_test.go

@@ -0,0 +1,118 @@
+// Package config_test provides tests for the config package.
+package config
+
+import (
+	"log/slog"
+	"os"
+	"testing"
+	"time"
+)
+
+func TestLoad(t *testing.T) {
+	// Clear environment
+	os.Clearenv()
+
+	cfg := Load()
+
+	if cfg.BaseURL != DefaultBaseURL {
+		t.Errorf("Expected BaseURL '%s', got '%s'", DefaultBaseURL, cfg.BaseURL)
+	}
+
+	if cfg.RequestTimeout != DefaultRequestTimeout {
+		t.Errorf("Expected timeout %v, got %v", DefaultRequestTimeout, cfg.RequestTimeout)
+	}
+
+	if cfg.LogLevel != DefaultLogLevel {
+		t.Errorf("Expected log level %v, got %v", DefaultLogLevel, cfg.LogLevel)
+	}
+
+	if cfg.LogFormat != DefaultLogFormat {
+		t.Errorf("Expected log format '%s', got '%s'", DefaultLogFormat, cfg.LogFormat)
+	}
+}
+
+func TestLoad_WithEnvironmentVariables(t *testing.T) {
+	// Set environment variables
+	os.Setenv("ARTICULATE_BASE_URL", "https://test.example.com")
+	os.Setenv("ARTICULATE_REQUEST_TIMEOUT", "60")
+	os.Setenv("LOG_LEVEL", "debug")
+	os.Setenv("LOG_FORMAT", "json")
+	defer os.Clearenv()
+
+	cfg := Load()
+
+	if cfg.BaseURL != "https://test.example.com" {
+		t.Errorf("Expected BaseURL 'https://test.example.com', got '%s'", cfg.BaseURL)
+	}
+
+	if cfg.RequestTimeout != 60*time.Second {
+		t.Errorf("Expected timeout 60s, got %v", cfg.RequestTimeout)
+	}
+
+	if cfg.LogLevel != slog.LevelDebug {
+		t.Errorf("Expected log level Debug, got %v", cfg.LogLevel)
+	}
+
+	if cfg.LogFormat != "json" {
+		t.Errorf("Expected log format 'json', got '%s'", cfg.LogFormat)
+	}
+}
+
+func TestGetLogLevelEnv(t *testing.T) {
+	tests := []struct {
+		name     string
+		value    string
+		expected slog.Level
+	}{
+		{"debug lowercase", "debug", slog.LevelDebug},
+		{"debug uppercase", "DEBUG", slog.LevelDebug},
+		{"info lowercase", "info", slog.LevelInfo},
+		{"info uppercase", "INFO", slog.LevelInfo},
+		{"warn lowercase", "warn", slog.LevelWarn},
+		{"warn uppercase", "WARN", slog.LevelWarn},
+		{"warning lowercase", "warning", slog.LevelWarn},
+		{"error lowercase", "error", slog.LevelError},
+		{"error uppercase", "ERROR", slog.LevelError},
+		{"invalid value", "invalid", slog.LevelInfo},
+		{"empty value", "", slog.LevelInfo},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			os.Clearenv()
+			if tt.value != "" {
+				os.Setenv("TEST_LOG_LEVEL", tt.value)
+			}
+			result := getLogLevelEnv("TEST_LOG_LEVEL", slog.LevelInfo)
+			if result != tt.expected {
+				t.Errorf("Expected %v, got %v", tt.expected, result)
+			}
+		})
+	}
+}
+
+func TestGetDurationEnv(t *testing.T) {
+	tests := []struct {
+		name     string
+		value    string
+		expected time.Duration
+	}{
+		{"valid duration", "45", 45 * time.Second},
+		{"zero duration", "0", 0},
+		{"invalid duration", "invalid", 30 * time.Second},
+		{"empty value", "", 30 * time.Second},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			os.Clearenv()
+			if tt.value != "" {
+				os.Setenv("TEST_DURATION", tt.value)
+			}
+			result := getDurationEnv("TEST_DURATION", 30*time.Second)
+			if result != tt.expected {
+				t.Errorf("Expected %v, got %v", tt.expected, result)
+			}
+		})
+	}
+}

internal/exporters/bench_test.go

@@ -0,0 +1,201 @@
+// Package exporters_test provides benchmarks for all exporters.
+package exporters
+
+import (
+	"path/filepath"
+	"testing"
+
+	"github.com/kjanat/articulate-parser/internal/models"
+	"github.com/kjanat/articulate-parser/internal/services"
+)
+
+// BenchmarkFactory_CreateExporter_Markdown benchmarks markdown exporter creation.
+func BenchmarkFactory_CreateExporter_Markdown(b *testing.B) {
+	htmlCleaner := services.NewHTMLCleaner()
+	factory := NewFactory(htmlCleaner)
+
+	b.ResetTimer()
+	for b.Loop() {
+		_, _ = factory.CreateExporter("markdown")
+	}
+}
+
+// BenchmarkFactory_CreateExporter_All benchmarks creating all exporter types.
+func BenchmarkFactory_CreateExporter_All(b *testing.B) {
+	htmlCleaner := services.NewHTMLCleaner()
+	factory := NewFactory(htmlCleaner)
+	formats := []string{"markdown", "docx", "html"}
+
+	b.ResetTimer()
+	for b.Loop() {
+		for _, format := range formats {
+			_, _ = factory.CreateExporter(format)
+		}
+	}
+}
+
+// BenchmarkAllExporters_Export benchmarks all exporters with the same course.
+func BenchmarkAllExporters_Export(b *testing.B) {
+	htmlCleaner := services.NewHTMLCleaner()
+	course := createBenchmarkCourse()
+
+	exporters := map[string]struct {
+		exporter any
+		ext      string
+	}{
+		"Markdown": {NewMarkdownExporter(htmlCleaner), ".md"},
+		"Docx":     {NewDocxExporter(htmlCleaner), ".docx"},
+		"HTML":     {NewHTMLExporter(htmlCleaner), ".html"},
+	}
+
+	for name, exp := range exporters {
+		b.Run(name, func(b *testing.B) {
+			tempDir := b.TempDir()
+			exporter := exp.exporter.(interface {
+				Export(*models.Course, string) error
+			})
+
+			b.ResetTimer()
+			for b.Loop() {
+				outputPath := filepath.Join(tempDir, "benchmark"+exp.ext)
+				_ = exporter.Export(course, outputPath)
+			}
+		})
+	}
+}
+
+// BenchmarkExporters_LargeCourse benchmarks exporters with large course data.
+func BenchmarkExporters_LargeCourse(b *testing.B) {
+	htmlCleaner := services.NewHTMLCleaner()
+	course := createLargeBenchmarkCourse()
+
+	b.Run("Markdown_Large", func(b *testing.B) {
+		exporter := NewMarkdownExporter(htmlCleaner)
+		tempDir := b.TempDir()
+
+		b.ResetTimer()
+		for b.Loop() {
+			outputPath := filepath.Join(tempDir, "large.md")
+			_ = exporter.Export(course, outputPath)
+		}
+	})
+
+	b.Run("Docx_Large", func(b *testing.B) {
+		exporter := NewDocxExporter(htmlCleaner)
+		tempDir := b.TempDir()
+
+		b.ResetTimer()
+		for b.Loop() {
+			outputPath := filepath.Join(tempDir, "large.docx")
+			_ = exporter.Export(course, outputPath)
+		}
+	})
+
+	b.Run("HTML_Large", func(b *testing.B) {
+		exporter := NewHTMLExporter(htmlCleaner)
+		tempDir := b.TempDir()
+
+		b.ResetTimer()
+		for b.Loop() {
+			outputPath := filepath.Join(tempDir, "large.html")
+			_ = exporter.Export(course, outputPath)
+		}
+	})
+}
+
+// createBenchmarkCourse creates a standard-sized course for benchmarking.
+func createBenchmarkCourse() *models.Course {
+	return &models.Course{
+		ShareID: "benchmark-id",
+		Author:  "Benchmark Author",
+		Course: models.CourseInfo{
+			ID:             "bench-course",
+			Title:          "Benchmark Course",
+			Description:    "Performance testing course",
+			NavigationMode: "menu",
+			Lessons: []models.Lesson{
+				{
+					ID:    "lesson1",
+					Title: "Introduction",
+					Type:  "lesson",
+					Items: []models.Item{
+						{
+							Type: "text",
+							Items: []models.SubItem{
+								{
+									Heading:   "Welcome",
+									Paragraph: "<p>This is a test paragraph with <strong>HTML</strong> content.</p>",
+								},
+							},
+						},
+						{
+							Type: "list",
+							Items: []models.SubItem{
+								{Paragraph: "Item 1"},
+								{Paragraph: "Item 2"},
+								{Paragraph: "Item 3"},
+							},
+						},
+					},
+				},
+			},
+		},
+	}
+}
+
+// createLargeBenchmarkCourse creates a large course for stress testing.
+func createLargeBenchmarkCourse() *models.Course {
+	lessons := make([]models.Lesson, 50)
+	for i := 0; i < 50; i++ {
+		lessons[i] = models.Lesson{
+			ID:          string(rune(i)),
+			Title:       "Lesson " + string(rune(i)),
+			Type:        "lesson",
+			Description: "<p>This is lesson description with <em>formatting</em>.</p>",
+			Items: []models.Item{
+				{
+					Type: "text",
+					Items: []models.SubItem{
+						{
+							Heading:   "Section Heading",
+							Paragraph: "<p>Content with <strong>bold</strong> and <em>italic</em> text.</p>",
+						},
+					},
+				},
+				{
+					Type: "list",
+					Items: []models.SubItem{
+						{Paragraph: "Point 1"},
+						{Paragraph: "Point 2"},
+						{Paragraph: "Point 3"},
+					},
+				},
+				{
+					Type: "knowledgeCheck",
+					Items: []models.SubItem{
+						{
+							Title: "Quiz Question",
+							Answers: []models.Answer{
+								{Title: "Answer A", Correct: false},
+								{Title: "Answer B", Correct: true},
+								{Title: "Answer C", Correct: false},
+							},
+							Feedback: "Good job!",
+						},
+					},
+				},
+			},
+		}
+	}
+
+	return &models.Course{
+		ShareID: "large-benchmark-id",
+		Author:  "Benchmark Author",
+		Course: models.CourseInfo{
+			ID:          "large-bench-course",
+			Title:       "Large Benchmark Course",
+			Description: "Large performance testing course",
+			Lessons:     lessons,
+		},
+	}
+}

internal/exporters/example_test.go

@@ -0,0 +1,101 @@
+// Package exporters_test provides examples for the exporters package.
+package exporters_test
+
+import (
+	"fmt"
+	"log"
+
+	"github.com/kjanat/articulate-parser/internal/exporters"
+	"github.com/kjanat/articulate-parser/internal/models"
+	"github.com/kjanat/articulate-parser/internal/services"
+)
+
+// ExampleNewFactory demonstrates creating an exporter factory.
+func ExampleNewFactory() {
+	htmlCleaner := services.NewHTMLCleaner()
+	factory := exporters.NewFactory(htmlCleaner)
+
+	// Get supported formats
+	formats := factory.SupportedFormats()
+	fmt.Printf("Supported formats: %d\n", len(formats))
+	// Output: Supported formats: 6
+}
+
+// ExampleFactory_CreateExporter demonstrates creating exporters.
+func ExampleFactory_CreateExporter() {
+	htmlCleaner := services.NewHTMLCleaner()
+	factory := exporters.NewFactory(htmlCleaner)
+
+	// Create a markdown exporter
+	exporter, err := factory.CreateExporter("markdown")
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	fmt.Printf("Created: %s exporter\n", exporter.SupportedFormat())
+	// Output: Created: markdown exporter
+}
+
+// ExampleFactory_CreateExporter_caseInsensitive demonstrates case-insensitive format names.
+func ExampleFactory_CreateExporter_caseInsensitive() {
+	htmlCleaner := services.NewHTMLCleaner()
+	factory := exporters.NewFactory(htmlCleaner)
+
+	// All these work (case-insensitive)
+	formats := []string{"MARKDOWN", "Markdown", "markdown", "MD"}
+
+	for _, format := range formats {
+		exporter, _ := factory.CreateExporter(format)
+		fmt.Printf("%s -> %s\n", format, exporter.SupportedFormat())
+	}
+	// Output:
+	// MARKDOWN -> markdown
+	// Markdown -> markdown
+	// markdown -> markdown
+	// MD -> markdown
+}
+
+// ExampleMarkdownExporter_Export demonstrates exporting to Markdown.
+func ExampleMarkdownExporter_Export() {
+	htmlCleaner := services.NewHTMLCleaner()
+	exporter := exporters.NewMarkdownExporter(htmlCleaner)
+
+	course := &models.Course{
+		ShareID: "example-id",
+		Course: models.CourseInfo{
+			Title:       "Example Course",
+			Description: "<p>Course description</p>",
+		},
+	}
+
+	// Export to markdown file
+	err := exporter.Export(course, "output.md")
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	fmt.Println("Export complete")
+	// Output: Export complete
+}
+
+// ExampleDocxExporter_Export demonstrates exporting to DOCX.
+func ExampleDocxExporter_Export() {
+	htmlCleaner := services.NewHTMLCleaner()
+	exporter := exporters.NewDocxExporter(htmlCleaner)
+
+	course := &models.Course{
+		ShareID: "example-id",
+		Course: models.CourseInfo{
+			Title: "Example Course",
+		},
+	}
+
+	// Export to Word document
+	err := exporter.Export(course, "output.docx")
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	fmt.Println("DOCX export complete")
+	// Output: DOCX export complete
+}

internal/exporters/factory.go

@@ -33,15 +33,7 @@ func NewFactory(htmlCleaner *services.HTMLCleaner) interfaces.ExporterFactory {
 }
 
 // CreateExporter creates an exporter for the specified format.
-// It returns an appropriate exporter implementation based on the format string.
-// Format strings are case-insensitive.
-//
-// Parameters:
-//   - format: The desired export format (e.g., "markdown", "docx")
-//
-// Returns:
-//   - An implementation of the Exporter interface if the format is supported
-//   - An error if the format is not supported
+// Format strings are case-insensitive (e.g., "markdown", "DOCX").
 func (f *Factory) CreateExporter(format string) (interfaces.Exporter, error) {
 	switch strings.ToLower(format) {
 	case "markdown", "md":
@@ -55,11 +47,8 @@ func (f *Factory) CreateExporter(format string) (interfaces.Exporter, error) {
 	}
 }
 
-// SupportedFormats returns a list of all supported export formats.
-// This includes both primary format names and their aliases.
-//
-// Returns:
-//   - A string slice containing all supported format names
+// SupportedFormats returns a list of all supported export formats,
+// including both primary format names and their aliases.
 func (f *Factory) SupportedFormats() []string {
 	return []string{"markdown", "md", "docx", "word", "html", "htm"}
 }

internal/exporters/markdown.go

@@ -36,16 +36,7 @@ func NewMarkdownExporter(htmlCleaner *services.HTMLCleaner) interfaces.Exporter
 	}
 }
 
-// Export exports a course to Markdown format.
-// It generates a structured Markdown document from the course data
-// and writes it to the specified output path.
-//
-// Parameters:
-//   - course: The course data model to export
-//   - outputPath: The file path where the Markdown content will be written
-//
-// Returns:
-//   - An error if writing to the output file fails
+// Export converts the course to Markdown format and writes it to the output path.
 func (e *MarkdownExporter) Export(course *models.Course, outputPath string) error {
 	var buf bytes.Buffer
 
@@ -92,23 +83,13 @@ func (e *MarkdownExporter) Export(course *models.Course, outputPath string) erro
 	return os.WriteFile(outputPath, buf.Bytes(), 0644)
 }
 
-// SupportedFormat returns the format name this exporter supports
-// It indicates the file format that the MarkdownExporter can generate.
-//
-// Returns:
-//   - A string representing the supported format ("markdown")
+// SupportedFormat returns "markdown".
 func (e *MarkdownExporter) SupportedFormat() string {
 	return "markdown"
 }
 
-// processItemToMarkdown converts a course item into Markdown format
-// and appends it to the provided buffer. It handles different item types
-// with appropriate Markdown formatting.
-//
-// Parameters:
-//   - buf: The buffer to write the Markdown content to
-//   - item: The course item to process
-//   - level: The heading level for the item (determines the number of # characters)
+// processItemToMarkdown converts a course item into Markdown format.
+// The level parameter determines the heading level (number of # characters).
 func (e *MarkdownExporter) processItemToMarkdown(buf *bytes.Buffer, item models.Item, level int) {
 	headingPrefix := strings.Repeat("#", level)
 

internal/exporters/output.md

@@ -0,0 +1,12 @@
+# Example Course
+
+Course description
+
+## Course Information
+
+- **Course ID**: 
+- **Share ID**: example-id
+- **Navigation Mode**: 
+
+---
+

internal/interfaces/logger.go

@@ -0,0 +1,27 @@
+// Package interfaces provides the core contracts for the articulate-parser application.
+// It defines interfaces for parsing and exporting Articulate Rise courses.
+package interfaces
+
+import "context"
+
+// Logger defines the interface for structured logging.
+// Implementations should provide leveled, structured logging capabilities.
+type Logger interface {
+	// Debug logs a debug-level message with optional key-value pairs.
+	Debug(msg string, keysAndValues ...any)
+
+	// Info logs an info-level message with optional key-value pairs.
+	Info(msg string, keysAndValues ...any)
+
+	// Warn logs a warning-level message with optional key-value pairs.
+	Warn(msg string, keysAndValues ...any)
+
+	// Error logs an error-level message with optional key-value pairs.
+	Error(msg string, keysAndValues ...any)
+
+	// With returns a new logger with the given key-value pairs added as context.
+	With(keysAndValues ...any) Logger
+
+	// WithContext returns a new logger with context information.
+	WithContext(ctx context.Context) Logger
+}

internal/services/app_test.go

@@ -2,6 +2,7 @@
 package services
 
 import (
+	"context"
 	"errors"
 	"testing"
 
@@ -11,13 +12,13 @@ import (
 
 // MockCourseParser is a mock implementation of interfaces.CourseParser for testing.
 type MockCourseParser struct {
-	mockFetchCourse        func(uri string) (*models.Course, error)
+	mockFetchCourse        func(ctx context.Context, uri string) (*models.Course, error)
 	mockLoadCourseFromFile func(filePath string) (*models.Course, error)
 }
 
-func (m *MockCourseParser) FetchCourse(uri string) (*models.Course, error) {
+func (m *MockCourseParser) FetchCourse(ctx context.Context, uri string) (*models.Course, error) {
 	if m.mockFetchCourse != nil {
-		return m.mockFetchCourse(uri)
+		return m.mockFetchCourse(ctx, uri)
 	}
 	return nil, errors.New("not implemented")
 }
@@ -243,7 +244,7 @@ func TestApp_ProcessCourseFromURI(t *testing.T) {
 			format:     "docx",
 			outputPath: "output.docx",
 			setupMocks: func(parser *MockCourseParser, factory *MockExporterFactory, exporter *MockExporter) {
-				parser.mockFetchCourse = func(uri string) (*models.Course, error) {
+				parser.mockFetchCourse = func(ctx context.Context, uri string) (*models.Course, error) {
 					if uri != "https://rise.articulate.com/share/test123" {
 						t.Errorf("Expected uri 'https://rise.articulate.com/share/test123', got '%s'", uri)
 					}
@@ -271,7 +272,7 @@ func TestApp_ProcessCourseFromURI(t *testing.T) {
 			format:     "docx",
 			outputPath: "output.docx",
 			setupMocks: func(parser *MockCourseParser, factory *MockExporterFactory, exporter *MockExporter) {
-				parser.mockFetchCourse = func(uri string) (*models.Course, error) {
+				parser.mockFetchCourse = func(ctx context.Context, uri string) (*models.Course, error) {
 					return nil, errors.New("network error")
 				}
 			},
@@ -288,7 +289,7 @@ func TestApp_ProcessCourseFromURI(t *testing.T) {
 			tt.setupMocks(parser, factory, exporter)
 
 			app := NewApp(parser, factory)
-			err := app.ProcessCourseFromURI(tt.uri, tt.format, tt.outputPath)
+			err := app.ProcessCourseFromURI(context.Background(), tt.uri, tt.format, tt.outputPath)
 
 			if tt.expectedError != "" {
 				if err == nil {

internal/services/example_test.go

@@ -0,0 +1,96 @@
+// Package services_test provides examples for the services package.
+package services_test
+
+import (
+	"context"
+	"fmt"
+	"log"
+
+	"github.com/kjanat/articulate-parser/internal/services"
+)
+
+// ExampleNewArticulateParser demonstrates creating a new parser.
+func ExampleNewArticulateParser() {
+	// Create a no-op logger for this example
+	logger := services.NewNoOpLogger()
+
+	// Create parser with defaults
+	parser := services.NewArticulateParser(logger, "", 0)
+
+	fmt.Printf("Parser created: %T\n", parser)
+	// Output: Parser created: *services.ArticulateParser
+}
+
+// ExampleNewArticulateParser_custom demonstrates creating a parser with custom configuration.
+func ExampleNewArticulateParser_custom() {
+	logger := services.NewNoOpLogger()
+
+	// Create parser with custom base URL and timeout
+	parser := services.NewArticulateParser(
+		logger,
+		"https://custom.articulate.com",
+		60_000_000_000, // 60 seconds in nanoseconds
+	)
+
+	fmt.Printf("Parser configured: %T\n", parser)
+	// Output: Parser configured: *services.ArticulateParser
+}
+
+// ExampleArticulateParser_LoadCourseFromFile demonstrates loading a course from a file.
+func ExampleArticulateParser_LoadCourseFromFile() {
+	logger := services.NewNoOpLogger()
+	parser := services.NewArticulateParser(logger, "", 0)
+
+	// In a real scenario, you'd have an actual file
+	// This example shows the API usage
+	_, err := parser.LoadCourseFromFile("course.json")
+	if err != nil {
+		log.Printf("Failed to load course: %v", err)
+	}
+}
+
+// ExampleArticulateParser_FetchCourse demonstrates fetching a course from a URI.
+func ExampleArticulateParser_FetchCourse() {
+	logger := services.NewNoOpLogger()
+	parser := services.NewArticulateParser(logger, "", 0)
+
+	// Create a context with timeout
+	ctx := context.Background()
+
+	// In a real scenario, you'd use an actual share URL
+	_, err := parser.FetchCourse(ctx, "https://rise.articulate.com/share/YOUR_SHARE_ID")
+	if err != nil {
+		log.Printf("Failed to fetch course: %v", err)
+	}
+}
+
+// ExampleHTMLCleaner demonstrates cleaning HTML content.
+func ExampleHTMLCleaner() {
+	cleaner := services.NewHTMLCleaner()
+
+	html := "<p>This is <strong>bold</strong> text with entities.</p>"
+	clean := cleaner.CleanHTML(html)
+
+	fmt.Println(clean)
+	// Output: This is bold text with entities.
+}
+
+// ExampleHTMLCleaner_CleanHTML demonstrates complex HTML cleaning.
+func ExampleHTMLCleaner_CleanHTML() {
+	cleaner := services.NewHTMLCleaner()
+
+	html := `
+		<div>
+			<h1>Title</h1>
+			<p>Paragraph with <a href="#">link</a> and &amp; entity.</p>
+			<ul>
+				<li>Item 1</li>
+				<li>Item 2</li>
+			</ul>
+		</div>
+	`
+	clean := cleaner.CleanHTML(html)
+
+	fmt.Println(clean)
+	// Output: Title Paragraph with link and & entity. Item 1 Item 2
+}

internal/services/html_cleaner.go

@@ -24,15 +24,9 @@ func NewHTMLCleaner() *HTMLCleaner {
 }
 
 // CleanHTML removes HTML tags and converts entities, returning clean plain text.
-// The function parses the HTML into a node tree and extracts only text content,
-// which handles edge cases like script tags or attributes better than regex.
-// It handles HTML entities automatically through the parser and normalizes whitespace.
-//
-// Parameters:
-//   - htmlStr: The HTML content to clean
-//
-// Returns:
-//   - A plain text string with all HTML elements and entities removed/converted
+// It parses the HTML into a node tree and extracts only text content,
+// skipping script and style tags. HTML entities are automatically handled
+// by the parser, and whitespace is normalized.
 func (h *HTMLCleaner) CleanHTML(htmlStr string) string {
 	// Parse the HTML into a node tree
 	doc, err := html.Parse(strings.NewReader(htmlStr))

internal/services/logger.go

@@ -0,0 +1,105 @@
+// Package services provides the core functionality for the articulate-parser application.
+package services
+
+import (
+	"context"
+	"log/slog"
+	"os"
+
+	"github.com/kjanat/articulate-parser/internal/interfaces"
+)
+
+// SlogLogger implements the Logger interface using the standard library's slog package.
+type SlogLogger struct {
+	logger *slog.Logger
+}
+
+// NewSlogLogger creates a new structured logger using slog.
+// The level parameter controls the minimum log level (debug, info, warn, error).
+func NewSlogLogger(level slog.Level) interfaces.Logger {
+	opts := &slog.HandlerOptions{
+		Level: level,
+	}
+	handler := slog.NewJSONHandler(os.Stdout, opts)
+	return &SlogLogger{
+		logger: slog.New(handler),
+	}
+}
+
+// NewTextLogger creates a new structured logger with human-readable text output.
+// Useful for development and debugging.
+func NewTextLogger(level slog.Level) interfaces.Logger {
+	opts := &slog.HandlerOptions{
+		Level: level,
+	}
+	handler := slog.NewTextHandler(os.Stdout, opts)
+	return &SlogLogger{
+		logger: slog.New(handler),
+	}
+}
+
+// Debug logs a debug-level message with optional key-value pairs.
+func (l *SlogLogger) Debug(msg string, keysAndValues ...any) {
+	l.logger.Debug(msg, keysAndValues...)
+}
+
+// Info logs an info-level message with optional key-value pairs.
+func (l *SlogLogger) Info(msg string, keysAndValues ...any) {
+	l.logger.Info(msg, keysAndValues...)
+}
+
+// Warn logs a warning-level message with optional key-value pairs.
+func (l *SlogLogger) Warn(msg string, keysAndValues ...any) {
+	l.logger.Warn(msg, keysAndValues...)
+}
+
+// Error logs an error-level message with optional key-value pairs.
+func (l *SlogLogger) Error(msg string, keysAndValues ...any) {
+	l.logger.Error(msg, keysAndValues...)
+}
+
+// With returns a new logger with the given key-value pairs added as context.
+func (l *SlogLogger) With(keysAndValues ...any) interfaces.Logger {
+	return &SlogLogger{
+		logger: l.logger.With(keysAndValues...),
+	}
+}
+
+// WithContext returns a new logger with context information.
+// Currently preserves the logger as-is, but can be extended to extract
+// trace IDs or other context values in the future.
+func (l *SlogLogger) WithContext(ctx context.Context) interfaces.Logger {
+	// Can be extended to extract trace IDs, request IDs, etc. from context
+	return l
+}
+
+// NoOpLogger is a logger that discards all log messages.
+// Useful for testing or when logging should be disabled.
+type NoOpLogger struct{}
+
+// NewNoOpLogger creates a logger that discards all messages.
+func NewNoOpLogger() interfaces.Logger {
+	return &NoOpLogger{}
+}
+
+// Debug does nothing.
+func (l *NoOpLogger) Debug(msg string, keysAndValues ...any) {}
+
+// Info does nothing.
+func (l *NoOpLogger) Info(msg string, keysAndValues ...any) {}
+
+// Warn does nothing.
+func (l *NoOpLogger) Warn(msg string, keysAndValues ...any) {}
+
+// Error does nothing.
+func (l *NoOpLogger) Error(msg string, keysAndValues ...any) {}
+
+// With returns the same no-op logger.
+func (l *NoOpLogger) With(keysAndValues ...any) interfaces.Logger {
+	return l
+}
+
+// WithContext returns the same no-op logger.
+func (l *NoOpLogger) WithContext(ctx context.Context) interfaces.Logger {
+	return l
+}

internal/services/logger_bench_test.go

@@ -0,0 +1,96 @@
+// Package services_test provides benchmarks for the logger implementations.
+package services
+
+import (
+	"context"
+	"io"
+	"log/slog"
+	"testing"
+)
+
+// BenchmarkSlogLogger_Info benchmarks structured JSON logging.
+func BenchmarkSlogLogger_Info(b *testing.B) {
+	// Create logger that writes to io.Discard to avoid benchmark noise
+	opts := &slog.HandlerOptions{Level: slog.LevelInfo}
+	handler := slog.NewJSONHandler(io.Discard, opts)
+	logger := &SlogLogger{logger: slog.New(handler)}
+
+	b.ResetTimer()
+	for b.Loop() {
+		logger.Info("test message", "key1", "value1", "key2", 42, "key3", true)
+	}
+}
+
+// BenchmarkSlogLogger_Debug benchmarks debug level logging.
+func BenchmarkSlogLogger_Debug(b *testing.B) {
+	opts := &slog.HandlerOptions{Level: slog.LevelDebug}
+	handler := slog.NewJSONHandler(io.Discard, opts)
+	logger := &SlogLogger{logger: slog.New(handler)}
+
+	b.ResetTimer()
+	for b.Loop() {
+		logger.Debug("debug message", "operation", "test", "duration", 123)
+	}
+}
+
+// BenchmarkSlogLogger_Error benchmarks error logging.
+func BenchmarkSlogLogger_Error(b *testing.B) {
+	opts := &slog.HandlerOptions{Level: slog.LevelError}
+	handler := slog.NewJSONHandler(io.Discard, opts)
+	logger := &SlogLogger{logger: slog.New(handler)}
+
+	b.ResetTimer()
+	for b.Loop() {
+		logger.Error("error occurred", "error", "test error", "code", 500)
+	}
+}
+
+// BenchmarkTextLogger_Info benchmarks text logging.
+func BenchmarkTextLogger_Info(b *testing.B) {
+	opts := &slog.HandlerOptions{Level: slog.LevelInfo}
+	handler := slog.NewTextHandler(io.Discard, opts)
+	logger := &SlogLogger{logger: slog.New(handler)}
+
+	b.ResetTimer()
+	for b.Loop() {
+		logger.Info("test message", "key1", "value1", "key2", 42)
+	}
+}
+
+// BenchmarkNoOpLogger benchmarks the no-op logger.
+func BenchmarkNoOpLogger(b *testing.B) {
+	logger := NewNoOpLogger()
+
+	b.ResetTimer()
+	for b.Loop() {
+		logger.Info("test message", "key1", "value1", "key2", 42)
+		logger.Error("error message", "error", "test")
+	}
+}
+
+// BenchmarkLogger_With benchmarks logger with context.
+func BenchmarkLogger_With(b *testing.B) {
+	opts := &slog.HandlerOptions{Level: slog.LevelInfo}
+	handler := slog.NewJSONHandler(io.Discard, opts)
+	logger := &SlogLogger{logger: slog.New(handler)}
+
+	b.ResetTimer()
+	for b.Loop() {
+		contextLogger := logger.With("request_id", "123", "user_id", "456")
+		contextLogger.Info("operation completed")
+	}
+}
+
+// BenchmarkLogger_WithContext benchmarks logger with Go context.
+func BenchmarkLogger_WithContext(b *testing.B) {
+	opts := &slog.HandlerOptions{Level: slog.LevelInfo}
+	handler := slog.NewJSONHandler(io.Discard, opts)
+	logger := &SlogLogger{logger: slog.New(handler)}
+	ctx := context.Background()
+
+	b.ResetTimer()
+	for b.Loop() {
+		contextLogger := logger.WithContext(ctx)
+		contextLogger.Info("context operation")
+	}
+}

internal/services/parser.go

@@ -24,32 +24,35 @@ type ArticulateParser struct {
 	BaseURL string
 	// Client is the HTTP client used to make requests to the API
 	Client *http.Client
+	// Logger for structured logging
+	Logger interfaces.Logger
 }
 
-// NewArticulateParser creates a new ArticulateParser instance with default settings.
-// The default configuration uses the standard Articulate Rise API URL and a
-// HTTP client with a 30-second timeout.
-func NewArticulateParser() interfaces.CourseParser {
+// NewArticulateParser creates a new ArticulateParser instance.
+// If baseURL is empty, uses the default Articulate Rise API URL.
+// If timeout is zero, uses a 30-second timeout.
+func NewArticulateParser(logger interfaces.Logger, baseURL string, timeout time.Duration) interfaces.CourseParser {
+	if logger == nil {
+		logger = NewNoOpLogger()
+	}
+	if baseURL == "" {
+		baseURL = "https://rise.articulate.com"
+	}
+	if timeout == 0 {
+		timeout = 30 * time.Second
+	}
 	return &ArticulateParser{
-		BaseURL: "https://rise.articulate.com",
+		BaseURL: baseURL,
 		Client: &http.Client{
-			Timeout: 30 * time.Second,
+			Timeout: timeout,
 		},
+		Logger: logger,
 	}
 }
 
-// FetchCourse fetches a course from the given URI.
-// It extracts the share ID from the URI, constructs an API URL, and fetches the course data.
-// The course data is then unmarshalled into a Course model.
-//
-// Parameters:
-//   - ctx: Context for cancellation and timeout control
-//   - uri: The Articulate Rise share URL (e.g., https://rise.articulate.com/share/SHARE_ID)
-//
-// Returns:
-//   - A parsed Course model if successful
-//   - An error if the fetch fails, if the share ID can't be extracted,
-//     or if the response can't be parsed
+// FetchCourse fetches a course from the given URI and returns the parsed course data.
+// The URI should be an Articulate Rise share URL (e.g., https://rise.articulate.com/share/SHARE_ID).
+// The context can be used for cancellation and timeout control.
 func (p *ArticulateParser) FetchCourse(ctx context.Context, uri string) (*models.Course, error) {
 	shareID, err := p.extractShareID(uri)
 	if err != nil {
@@ -73,7 +76,7 @@ func (p *ArticulateParser) FetchCourse(ctx context.Context, uri string) (*models
 	// connection, but a close error doesn't invalidate the data already consumed.
 	defer func() {
 		if err := resp.Body.Close(); err != nil {
-			fmt.Fprintf(os.Stderr, "warning: failed to close response body: %v\n", err)
+			p.Logger.Warn("failed to close response body", "error", err, "url", apiURL)
 		}
 	}()
 
@@ -95,14 +98,6 @@ func (p *ArticulateParser) FetchCourse(ctx context.Context, uri string) (*models
 }
 
 // LoadCourseFromFile loads an Articulate Rise course from a local JSON file.
-// The file should contain a valid JSON representation of an Articulate Rise course.
-//
-// Parameters:
-//   - filePath: The path to the JSON file containing the course data
-//
-// Returns:
-//   - A parsed Course model if successful
-//   - An error if the file can't be read or the JSON can't be parsed
 func (p *ArticulateParser) LoadCourseFromFile(filePath string) (*models.Course, error) {
 	data, err := os.ReadFile(filePath)
 	if err != nil {

internal/services/parser_bench_test.go

@@ -0,0 +1,216 @@
+// Package services_test provides benchmarks for the parser service.
+package services
+
+import (
+	"context"
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"os"
+	"path/filepath"
+	"testing"
+
+	"github.com/kjanat/articulate-parser/internal/models"
+)
+
+// BenchmarkArticulateParser_FetchCourse benchmarks the FetchCourse method.
+func BenchmarkArticulateParser_FetchCourse(b *testing.B) {
+	testCourse := &models.Course{
+		ShareID: "benchmark-id",
+		Author:  "Benchmark Author",
+		Course: models.CourseInfo{
+			ID:          "bench-course",
+			Title:       "Benchmark Course",
+			Description: "Testing performance",
+			Lessons: []models.Lesson{
+				{
+					ID:    "lesson1",
+					Title: "Lesson 1",
+					Type:  "lesson",
+				},
+			},
+		},
+	}
+
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", "application/json")
+		json.NewEncoder(w).Encode(testCourse)
+	}))
+	defer server.Close()
+
+	parser := &ArticulateParser{
+		BaseURL: server.URL,
+		Client:  &http.Client{},
+		Logger:  NewNoOpLogger(),
+	}
+
+	b.ResetTimer()
+	for b.Loop() {
+		_, err := parser.FetchCourse(context.Background(), "https://rise.articulate.com/share/benchmark-id")
+		if err != nil {
+			b.Fatalf("FetchCourse failed: %v", err)
+		}
+	}
+}
+
+// BenchmarkArticulateParser_FetchCourse_LargeCourse benchmarks with a large course.
+func BenchmarkArticulateParser_FetchCourse_LargeCourse(b *testing.B) {
+	// Create a large course with many lessons
+	lessons := make([]models.Lesson, 100)
+	for i := 0; i < 100; i++ {
+		lessons[i] = models.Lesson{
+			ID:          string(rune(i)),
+			Title:       "Lesson " + string(rune(i)),
+			Type:        "lesson",
+			Description: "This is a test lesson with some description",
+			Items: []models.Item{
+				{
+					Type: "text",
+					Items: []models.SubItem{
+						{
+							Heading:   "Test Heading",
+							Paragraph: "Test paragraph content with some text",
+						},
+					},
+				},
+			},
+		}
+	}
+
+	testCourse := &models.Course{
+		ShareID: "large-course-id",
+		Author:  "Benchmark Author",
+		Course: models.CourseInfo{
+			ID:          "large-course",
+			Title:       "Large Benchmark Course",
+			Description: "Testing performance with large course",
+			Lessons:     lessons,
+		},
+	}
+
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", "application/json")
+		json.NewEncoder(w).Encode(testCourse)
+	}))
+	defer server.Close()
+
+	parser := &ArticulateParser{
+		BaseURL: server.URL,
+		Client:  &http.Client{},
+		Logger:  NewNoOpLogger(),
+	}
+
+	b.ResetTimer()
+	for b.Loop() {
+		_, err := parser.FetchCourse(context.Background(), "https://rise.articulate.com/share/large-course-id")
+		if err != nil {
+			b.Fatalf("FetchCourse failed: %v", err)
+		}
+	}
+}
+
+// BenchmarkArticulateParser_LoadCourseFromFile benchmarks loading from file.
+func BenchmarkArticulateParser_LoadCourseFromFile(b *testing.B) {
+	testCourse := &models.Course{
+		ShareID: "file-test-id",
+		Course: models.CourseInfo{
+			Title: "File Test Course",
+		},
+	}
+
+	tempDir := b.TempDir()
+	tempFile := filepath.Join(tempDir, "benchmark.json")
+
+	data, err := json.Marshal(testCourse)
+	if err != nil {
+		b.Fatalf("Failed to marshal: %v", err)
+	}
+
+	if err := os.WriteFile(tempFile, data, 0644); err != nil {
+		b.Fatalf("Failed to write file: %v", err)
+	}
+
+	parser := NewArticulateParser(nil, "", 0)
+
+	b.ResetTimer()
+	for b.Loop() {
+		_, err := parser.LoadCourseFromFile(tempFile)
+		if err != nil {
+			b.Fatalf("LoadCourseFromFile failed: %v", err)
+		}
+	}
+}
+
+// BenchmarkArticulateParser_LoadCourseFromFile_Large benchmarks with large file.
+func BenchmarkArticulateParser_LoadCourseFromFile_Large(b *testing.B) {
+	// Create a large course
+	lessons := make([]models.Lesson, 200)
+	for i := 0; i < 200; i++ {
+		lessons[i] = models.Lesson{
+			ID:    string(rune(i)),
+			Title: "Lesson " + string(rune(i)),
+			Type:  "lesson",
+			Items: []models.Item{
+				{Type: "text", Items: []models.SubItem{{Heading: "H", Paragraph: "P"}}},
+				{Type: "list", Items: []models.SubItem{{Paragraph: "Item 1"}, {Paragraph: "Item 2"}}},
+			},
+		}
+	}
+
+	testCourse := &models.Course{
+		ShareID: "large-file-id",
+		Course: models.CourseInfo{
+			Title:   "Large File Course",
+			Lessons: lessons,
+		},
+	}
+
+	tempDir := b.TempDir()
+	tempFile := filepath.Join(tempDir, "large-benchmark.json")
+
+	data, err := json.Marshal(testCourse)
+	if err != nil {
+		b.Fatalf("Failed to marshal: %v", err)
+	}
+
+	if err := os.WriteFile(tempFile, data, 0644); err != nil {
+		b.Fatalf("Failed to write file: %v", err)
+	}
+
+	parser := NewArticulateParser(nil, "", 0)
+
+	b.ResetTimer()
+	for b.Loop() {
+		_, err := parser.LoadCourseFromFile(tempFile)
+		if err != nil {
+			b.Fatalf("LoadCourseFromFile failed: %v", err)
+		}
+	}
+}
+
+// BenchmarkArticulateParser_ExtractShareID benchmarks share ID extraction.
+func BenchmarkArticulateParser_ExtractShareID(b *testing.B) {
+	parser := &ArticulateParser{}
+	uri := "https://rise.articulate.com/share/N_APNg40Vr2CSH2xNz-ZLATM5kNviDIO#/"
+
+	b.ResetTimer()
+	for b.Loop() {
+		_, err := parser.extractShareID(uri)
+		if err != nil {
+			b.Fatalf("extractShareID failed: %v", err)
+		}
+	}
+}
+
+// BenchmarkArticulateParser_BuildAPIURL benchmarks API URL building.
+func BenchmarkArticulateParser_BuildAPIURL(b *testing.B) {
+	parser := &ArticulateParser{
+		BaseURL: "https://rise.articulate.com",
+	}
+	shareID := "test-share-id-12345"
+
+	b.ResetTimer()
+	for b.Loop() {
+		_ = parser.buildAPIURL(shareID)
+	}
+}

internal/services/parser_context_test.go

@@ -0,0 +1,285 @@
+// Package services_test provides context-aware tests for the parser service.
+package services
+
+import (
+	"context"
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/kjanat/articulate-parser/internal/models"
+)
+
+// TestArticulateParser_FetchCourse_ContextCancellation tests that FetchCourse
+// respects context cancellation.
+func TestArticulateParser_FetchCourse_ContextCancellation(t *testing.T) {
+	// Create a server that delays response
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		// Sleep to give time for context cancellation
+		time.Sleep(100 * time.Millisecond)
+
+		testCourse := &models.Course{
+			ShareID: "test-id",
+			Course: models.CourseInfo{
+				Title: "Test Course",
+			},
+		}
+		json.NewEncoder(w).Encode(testCourse)
+	}))
+	defer server.Close()
+
+	parser := &ArticulateParser{
+		BaseURL: server.URL,
+		Client: &http.Client{
+			Timeout: 5 * time.Second,
+		},
+		Logger: NewNoOpLogger(),
+	}
+
+	// Create a context that we'll cancel immediately
+	ctx, cancel := context.WithCancel(context.Background())
+	cancel() // Cancel immediately
+
+	_, err := parser.FetchCourse(ctx, "https://rise.articulate.com/share/test-id")
+
+	// Should get a context cancellation error
+	if err == nil {
+		t.Fatal("Expected error due to context cancellation, got nil")
+	}
+
+	if !strings.Contains(err.Error(), "context canceled") {
+		t.Errorf("Expected context cancellation error, got: %v", err)
+	}
+}
+
+// TestArticulateParser_FetchCourse_ContextTimeout tests that FetchCourse
+// respects context timeout.
+func TestArticulateParser_FetchCourse_ContextTimeout(t *testing.T) {
+	// Create a server that delays response longer than timeout
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		// Sleep longer than the context timeout
+		time.Sleep(200 * time.Millisecond)
+
+		testCourse := &models.Course{
+			ShareID: "test-id",
+			Course: models.CourseInfo{
+				Title: "Test Course",
+			},
+		}
+		json.NewEncoder(w).Encode(testCourse)
+	}))
+	defer server.Close()
+
+	parser := &ArticulateParser{
+		BaseURL: server.URL,
+		Client: &http.Client{
+			Timeout: 5 * time.Second,
+		},
+		Logger: NewNoOpLogger(),
+	}
+
+	// Create a context with a very short timeout
+	ctx, cancel := context.WithTimeout(context.Background(), 50*time.Millisecond)
+	defer cancel()
+
+	_, err := parser.FetchCourse(ctx, "https://rise.articulate.com/share/test-id")
+
+	// Should get a context deadline exceeded error
+	if err == nil {
+		t.Fatal("Expected error due to context timeout, got nil")
+	}
+
+	if !strings.Contains(err.Error(), "deadline exceeded") &&
+		!strings.Contains(err.Error(), "context deadline exceeded") {
+		t.Errorf("Expected context timeout error, got: %v", err)
+	}
+}
+
+// TestArticulateParser_FetchCourse_ContextDeadline tests that FetchCourse
+// respects context deadline.
+func TestArticulateParser_FetchCourse_ContextDeadline(t *testing.T) {
+	// Create a server that delays response
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		time.Sleep(150 * time.Millisecond)
+
+		testCourse := &models.Course{
+			ShareID: "test-id",
+			Course: models.CourseInfo{
+				Title: "Test Course",
+			},
+		}
+		json.NewEncoder(w).Encode(testCourse)
+	}))
+	defer server.Close()
+
+	parser := &ArticulateParser{
+		BaseURL: server.URL,
+		Client: &http.Client{
+			Timeout: 5 * time.Second,
+		},
+		Logger: NewNoOpLogger(),
+	}
+
+	// Create a context with a deadline in the past
+	ctx, cancel := context.WithDeadline(context.Background(), time.Now().Add(10*time.Millisecond))
+	defer cancel()
+
+	_, err := parser.FetchCourse(ctx, "https://rise.articulate.com/share/test-id")
+
+	// Should get a deadline exceeded error
+	if err == nil {
+		t.Fatal("Expected error due to context deadline, got nil")
+	}
+
+	if !strings.Contains(err.Error(), "deadline exceeded") &&
+		!strings.Contains(err.Error(), "context deadline exceeded") {
+		t.Errorf("Expected deadline exceeded error, got: %v", err)
+	}
+}
+
+// TestArticulateParser_FetchCourse_ContextSuccess tests that FetchCourse
+// succeeds when context is not cancelled.
+func TestArticulateParser_FetchCourse_ContextSuccess(t *testing.T) {
+	testCourse := &models.Course{
+		ShareID: "test-id",
+		Course: models.CourseInfo{
+			Title: "Test Course",
+		},
+	}
+
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		// Respond quickly
+		json.NewEncoder(w).Encode(testCourse)
+	}))
+	defer server.Close()
+
+	parser := &ArticulateParser{
+		BaseURL: server.URL,
+		Client: &http.Client{
+			Timeout: 5 * time.Second,
+		},
+		Logger: NewNoOpLogger(),
+	}
+
+	// Create a context with generous timeout
+	ctx, cancel := context.WithTimeout(context.Background(), 2*time.Second)
+	defer cancel()
+
+	course, err := parser.FetchCourse(ctx, "https://rise.articulate.com/share/test-id")
+
+	if err != nil {
+		t.Fatalf("Expected no error, got: %v", err)
+	}
+
+	if course == nil {
+		t.Fatal("Expected course, got nil")
+	}
+
+	if course.Course.Title != testCourse.Course.Title {
+		t.Errorf("Expected title '%s', got '%s'", testCourse.Course.Title, course.Course.Title)
+	}
+}
+
+// TestArticulateParser_FetchCourse_CancellationDuringRequest tests cancellation
+// during an in-flight request.
+func TestArticulateParser_FetchCourse_CancellationDuringRequest(t *testing.T) {
+	requestStarted := make(chan bool)
+
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		requestStarted <- true
+		// Keep the handler running to simulate slow response
+		time.Sleep(300 * time.Millisecond)
+
+		testCourse := &models.Course{
+			ShareID: "test-id",
+		}
+		json.NewEncoder(w).Encode(testCourse)
+	}))
+	defer server.Close()
+
+	parser := &ArticulateParser{
+		BaseURL: server.URL,
+		Client: &http.Client{
+			Timeout: 5 * time.Second,
+		},
+		Logger: NewNoOpLogger(),
+	}
+
+	ctx, cancel := context.WithCancel(context.Background())
+
+	// Start the request in a goroutine
+	errChan := make(chan error, 1)
+	go func() {
+		_, err := parser.FetchCourse(ctx, "https://rise.articulate.com/share/test-id")
+		errChan <- err
+	}()
+
+	// Wait for request to start
+	<-requestStarted
+
+	// Cancel after request has started
+	cancel()
+
+	// Get the error
+	err := <-errChan
+
+	if err == nil {
+		t.Fatal("Expected error due to context cancellation, got nil")
+	}
+
+	// Should contain context canceled somewhere in the error chain
+	if !strings.Contains(err.Error(), "context canceled") {
+		t.Errorf("Expected context canceled error, got: %v", err)
+	}
+}
+
+// TestArticulateParser_FetchCourse_MultipleTimeouts tests behavior with
+// multiple concurrent requests and timeouts.
+func TestArticulateParser_FetchCourse_MultipleTimeouts(t *testing.T) {
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		time.Sleep(100 * time.Millisecond)
+		testCourse := &models.Course{ShareID: "test"}
+		json.NewEncoder(w).Encode(testCourse)
+	}))
+	defer server.Close()
+
+	parser := &ArticulateParser{
+		BaseURL: server.URL,
+		Client: &http.Client{
+			Timeout: 5 * time.Second,
+		},
+		Logger: NewNoOpLogger(),
+	}
+
+	// Launch multiple requests with different timeouts
+	tests := []struct {
+		name          string
+		timeout       time.Duration
+		shouldSucceed bool
+	}{
+		{"very short timeout", 10 * time.Millisecond, false},
+		{"short timeout", 50 * time.Millisecond, false},
+		{"adequate timeout", 500 * time.Millisecond, true},
+		{"long timeout", 2 * time.Second, true},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			ctx, cancel := context.WithTimeout(context.Background(), tt.timeout)
+			defer cancel()
+
+			_, err := parser.FetchCourse(ctx, "https://rise.articulate.com/share/test-id")
+
+			if tt.shouldSucceed && err != nil {
+				t.Errorf("Expected success with timeout %v, got error: %v", tt.timeout, err)
+			}
+
+			if !tt.shouldSucceed && err == nil {
+				t.Errorf("Expected timeout error with timeout %v, got success", tt.timeout)
+			}
+		})
+	}
+}

internal/services/parser_test.go

@@ -2,6 +2,7 @@
 package services
 
 import (
+	"context"
 	"encoding/json"
 	"net/http"
 	"net/http/httptest"
@@ -16,7 +17,7 @@ import (
 
 // TestNewArticulateParser tests the NewArticulateParser constructor.
 func TestNewArticulateParser(t *testing.T) {
-	parser := NewArticulateParser()
+	parser := NewArticulateParser(nil, "", 0)
 
 	if parser == nil {
 		t.Fatal("NewArticulateParser() returned nil")
@@ -112,7 +113,7 @@ func TestArticulateParser_FetchCourse(t *testing.T) {
 
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			course, err := parser.FetchCourse(tt.uri)
+			course, err := parser.FetchCourse(context.Background(), tt.uri)
 
 			if tt.expectedError != "" {
 				if err == nil {
@@ -146,7 +147,7 @@ func TestArticulateParser_FetchCourse_NetworkError(t *testing.T) {
 		},
 	}
 
-	_, err := parser.FetchCourse("https://rise.articulate.com/share/test-share-id")
+	_, err := parser.FetchCourse(context.Background(), "https://rise.articulate.com/share/test-share-id")
 	if err == nil {
 		t.Fatal("Expected network error, got nil")
 	}
@@ -175,7 +176,7 @@ func TestArticulateParser_FetchCourse_InvalidJSON(t *testing.T) {
 		},
 	}
 
-	_, err := parser.FetchCourse("https://rise.articulate.com/share/test-share-id")
+	_, err := parser.FetchCourse(context.Background(), "https://rise.articulate.com/share/test-share-id")
 	if err == nil {
 		t.Fatal("Expected JSON parsing error, got nil")
 	}
@@ -212,7 +213,7 @@ func TestArticulateParser_LoadCourseFromFile(t *testing.T) {
 		t.Fatalf("Failed to write test file: %v", err)
 	}
 
-	parser := NewArticulateParser()
+	parser := NewArticulateParser(nil, "", 0)
 
 	tests := []struct {
 		name          string
@@ -271,7 +272,7 @@ func TestArticulateParser_LoadCourseFromFile_InvalidJSON(t *testing.T) {
 		t.Fatalf("Failed to write test file: %v", err)
 	}
 
-	parser := NewArticulateParser()
+	parser := NewArticulateParser(nil, "", 0)
 	_, err := parser.LoadCourseFromFile(tempFile)
 
 	if err == nil {

main.go

@@ -4,12 +4,14 @@
 package main
 
 import (
+	"context"
 	"fmt"
-	"log"
 	"os"
 	"strings"
 
+	"github.com/kjanat/articulate-parser/internal/config"
 	"github.com/kjanat/articulate-parser/internal/exporters"
+	"github.com/kjanat/articulate-parser/internal/interfaces"
 	"github.com/kjanat/articulate-parser/internal/services"
 	"github.com/kjanat/articulate-parser/internal/version"
 )
@@ -24,9 +26,19 @@ func main() {
 // run contains the main application logic and returns an exit code.
 // This function is testable as it doesn't call os.Exit directly.
 func run(args []string) int {
-	// Dependency injection setup
+	// Load configuration
+	cfg := config.Load()
+
+	// Dependency injection setup with configuration
+	var logger interfaces.Logger
+	if cfg.LogFormat == "json" {
+		logger = services.NewSlogLogger(cfg.LogLevel)
+	} else {
+		logger = services.NewTextLogger(cfg.LogLevel)
+	}
+
 	htmlCleaner := services.NewHTMLCleaner()
-	parser := services.NewArticulateParser()
+	parser := services.NewArticulateParser(logger, cfg.BaseURL, cfg.RequestTimeout)
 	exporterFactory := exporters.NewFactory(htmlCleaner)
 	app := services.NewApp(parser, exporterFactory)
 
@@ -58,17 +70,17 @@ func run(args []string) int {
 
 	// Determine if source is a URI or file path
 	if isURI(source) {
-		err = app.ProcessCourseFromURI(source, format, output)
+		err = app.ProcessCourseFromURI(context.Background(), source, format, output)
 	} else {
 		err = app.ProcessCourseFromFile(source, format, output)
 	}
 
 	if err != nil {
-		log.Printf("Error processing course: %v", err)
+		logger.Error("failed to process course", "error", err, "source", source)
 		return 1
 	}
 
-	fmt.Printf("Successfully exported course to %s\n", output)
+	logger.Info("successfully exported course", "output", output, "format", format)
 	return 0
 }
 

main_test.go

@@ -3,7 +3,6 @@ package main
 
 import (
 	"bytes"
-	"fmt"
 	"io"
 	"log"
 	"os"
@@ -297,10 +296,10 @@ func TestRunWithInvalidFile(t *testing.T) {
 		t.Errorf("Expected exit code 1 for non-existent file, got %d", exitCode)
 	}
 
-	// Should have error output
-	errorOutput := stderrBuf.String()
-	if !strings.Contains(errorOutput, "Error processing course") {
-		t.Errorf("Expected error message about processing course, got: %s", errorOutput)
+	// Should have error output in structured log format
+	output := stdoutBuf.String()
+	if !strings.Contains(output, "level=ERROR") && !strings.Contains(output, "failed to process course") {
+		t.Errorf("Expected error message about processing course, got: %s", output)
 	}
 }
 
@@ -350,10 +349,10 @@ func TestRunWithInvalidURI(t *testing.T) {
 		t.Errorf("Expected failure (exit code 1) for invalid URI, got %d", exitCode)
 	}
 
-	// Should have error output
-	errorOutput := stderrBuf.String()
-	if !strings.Contains(errorOutput, "Error processing course") {
-		t.Errorf("Expected error message about processing course, got: %s", errorOutput)
+	// Should have error output in structured log format
+	output := stdoutBuf.String()
+	if !strings.Contains(output, "level=ERROR") && !strings.Contains(output, "failed to process course") {
+		t.Errorf("Expected error message about processing course, got: %s", output)
 	}
 }
 
@@ -436,10 +435,9 @@ func TestRunWithValidJSONFile(t *testing.T) {
 		t.Errorf("Expected successful execution (exit code 0), got %d", exitCode)
 	}
 
-	// Verify success message
-	expectedMsg := fmt.Sprintf("Successfully exported course to %s", outputFile)
-	if !strings.Contains(output, expectedMsg) {
-		t.Errorf("Expected success message '%s' in output, got: %s", expectedMsg, output)
+	// Verify success message in structured log format
+	if !strings.Contains(output, "level=INFO") || !strings.Contains(output, "successfully exported course") {
+		t.Errorf("Expected success message in output, got: %s", output)
 	}
 
 	// Verify output file was created