// Package blender handles Blender binary management and execution.
package blender

import (
	"fmt"
	"log"
	"os"
	"path/filepath"

	"jiggablend/internal/runner/api"
	"jiggablend/internal/runner/workspace"
)

// Manager handles Blender binary downloads and management.
type Manager struct {
	manager      *api.ManagerClient
	workspaceDir string
}

// NewManager creates a new Blender manager.
func NewManager(managerClient *api.ManagerClient, workspaceDir string) *Manager {
	return &Manager{
		manager:      managerClient,
		workspaceDir: workspaceDir,
	}
}

// GetBinaryPath returns the path to the Blender binary for a specific version.
// Downloads from manager and extracts if not already present.
func (m *Manager) GetBinaryPath(version string) (string, error) {
	blenderDir := filepath.Join(m.workspaceDir, "blender-versions")
	if err := os.MkdirAll(blenderDir, 0755); err != nil {
		return "", fmt.Errorf("failed to create blender directory: %w", err)
	}

	// Check if already installed - look for version folder first
	versionDir := filepath.Join(blenderDir, version)
	binaryPath := filepath.Join(versionDir, "blender")

	// Check if version folder exists and contains the binary
	if versionInfo, err := os.Stat(versionDir); err == nil && versionInfo.IsDir() {
		// Version folder exists, check if binary is present
		if binaryInfo, err := os.Stat(binaryPath); err == nil {
			// Verify it's actually a file (not a directory)
			if !binaryInfo.IsDir() {
				log.Printf("Found existing Blender %s installation at %s", version, binaryPath)
				return binaryPath, nil
			}
		}
		// Version folder exists but binary is missing - might be incomplete installation
		log.Printf("Version folder %s exists but binary not found, will re-download", versionDir)
	}

	// Download from manager
	log.Printf("Downloading Blender %s from manager", version)

	reader, err := m.manager.DownloadBlender(version)
	if err != nil {
		return "", err
	}
	defer reader.Close()

	// Manager serves pre-decompressed .tar files - extract directly
	log.Printf("Extracting Blender %s...", version)
	if err := workspace.ExtractTarStripPrefix(reader, versionDir); err != nil {
		return "", fmt.Errorf("failed to extract blender: %w", err)
	}

	// Verify binary exists
	if _, err := os.Stat(binaryPath); err != nil {
		return "", fmt.Errorf("blender binary not found after extraction")
	}

	log.Printf("Blender %s installed at %s", version, binaryPath)
	return binaryPath, nil
}

// GetBinaryForJob returns the Blender binary path for a job.
// Uses the version from metadata or falls back to system blender.
func (m *Manager) GetBinaryForJob(version string) (string, error) {
	if version == "" {
		return "blender", nil // System blender
	}

	return m.GetBinaryPath(version)
}