Add strict pipeline and session config loading

internal/config/validate.go

@@ -1,8 +1,90 @@
 package config
 
-import "fmt"
+import (
+	"fmt"
+	"strings"
+	"time"
+)
 
-// Validate is a placeholder for configuration validation logic.
-func Validate(_ *Config) error {
-	return fmt.Errorf("config validation: not yet implemented")
+// Validate checks resolved configuration for required fields and parseable durations.
+func Validate(cfg *Config) error {
+	if cfg == nil {
+		return fmt.Errorf("config is nil")
+	}
+	if cfg.Pipeline == nil {
+		return fmt.Errorf("pipeline config is required")
+	}
+	if cfg.Session == nil {
+		return fmt.Errorf("session config is required")
+	}
+
+	if err := validatePipeline(cfg.Pipeline); err != nil {
+		return err
+	}
+	if err := validateSession(cfg.Session); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func validatePipeline(cfg *PipelineConfig) error {
+	if strings.TrimSpace(cfg.Workspace.Root) == "" {
+		return fmt.Errorf("pipeline.workspace.root is required")
+	}
+
+	if err := validateDuration("pipeline.whisperx.timeout", cfg.WhisperX.Timeout); err != nil {
+		return err
+	}
+	if err := validateDuration("pipeline.seriatim.timeout", cfg.Seriatim.Timeout); err != nil {
+		return err
+	}
+	if err := validateDuration("pipeline.audita.timeout", cfg.Audita.Timeout); err != nil {
+		return err
+	}
+	if err := validateDuration("pipeline.analyzer.timeout", cfg.Analyzer.Timeout); err != nil {
+		return err
+	}
+	if err := validateDuration("pipeline.notification.timeout", cfg.Notification.Timeout); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func validateSession(cfg *SessionConfig) error {
+	if strings.TrimSpace(cfg.SessionID) == "" {
+		return fmt.Errorf("session.session_id is required")
+	}
+
+	if strings.TrimSpace(cfg.Inputs.SpeakersFile) == "" {
+		return fmt.Errorf("session.inputs.speakers_file is required")
+	}
+	if strings.TrimSpace(cfg.Inputs.AutocorrectFile) == "" {
+		return fmt.Errorf("session.inputs.autocorrect_file is required")
+	}
+	if strings.TrimSpace(cfg.Inputs.GlossaryFile) == "" {
+		return fmt.Errorf("session.inputs.glossary_file is required")
+	}
+
+	hasAudioDir := strings.TrimSpace(cfg.Inputs.AudioDir) != ""
+	hasAudioFiles := len(cfg.Inputs.AudioFiles) > 0
+	if !hasAudioDir && !hasAudioFiles {
+		return fmt.Errorf("session.inputs requires audio_dir or at least one audio_files entry")
+	}
+
+	return nil
+}
+
+func validateDuration(fieldName, value string) error {
+	trimmed := strings.TrimSpace(value)
+	if trimmed == "" {
+		return nil
+	}
+
+	if _, err := time.ParseDuration(trimmed); err != nil {
+		return fmt.Errorf("%s must be a valid duration: %w", fieldName, err)
+	}
+
+	return nil
 }