// Path: Backend/internal/posixproj/projector.go

package posixproj

import (
	"context"
	"fmt"
	"strings"

	"moku-backend/internal/database"
)

func NewProjector(db *database.DB, root string) *Projector {
	return &Projector{db: db, root: strings.TrimSpace(root)}
}

func (projector *Projector) Rebuild(ctx context.Context) error {
	_, err := projector.RebuildWithSummary(ctx)
	return err
}

func (projector *Projector) RebuildWithSummary(ctx context.Context) (RebuildSummary, error) {
	if projector == nil || projector.db == nil || projector.db.Pool == nil {
		return RebuildSummary{}, nil
	}

	nodes, err := ScanRoot(projector.root)
	if err != nil {
		return RebuildSummary{}, err
	}

	summary := summarizeNodes(nodes)

	tx, err := projector.db.Pool.Begin(ctx)
	if err != nil {
		return RebuildSummary{}, err
	}
	defer func() {
		_ = tx.Rollback(ctx)
	}()

	if _, err := tx.Exec(ctx, `DELETE FROM posix_nodes;`); err != nil {
		return RebuildSummary{}, fmt.Errorf("clear posix_nodes: %w", err)
	}

	for _, node := range nodes {
		if _, err := tx.Exec(ctx, `
			INSERT INTO posix_nodes (
				path,
				parent_path,
				name,
				depth,
				node_kind,
				logical_type,
				file_role,
				resource_id,
				resource_name,
				resource_slug,
				installation_id,
				organization_id,
				organization_slug,
				department_slug,
				team_slug,
				project_slug,
				personal_slug,
				content_json,
				size_bytes,
				checksum
			) VALUES (
				$1, $2, $3, $4, $5::posix_node_kind, $6, $7, $8, $9, $10,
				$11, $12, $13, $14, $15, $16, $17, $18::jsonb, $19, $20
			);
		`,
			node.Path,
			node.ParentPath,
			node.Name,
			node.Depth,
			string(node.NodeKind),
			node.LogicalType,
			node.FileRole,
			node.ResourceID,
			node.ResourceName,
			node.ResourceSlug,
			node.InstallationID,
			node.OrganizationID,
			node.OrganizationSlug,
			node.DepartmentSlug,
			node.TeamSlug,
			node.ProjectSlug,
			node.PersonalSlug,
			node.ContentJSON,
			node.SizeBytes,
			node.Checksum,
		); err != nil {
			return RebuildSummary{}, fmt.Errorf("insert posix node %s: %w", node.Path, err)
		}
	}

	if err := tx.Commit(ctx); err != nil {
		return RebuildSummary{}, err
	}

	return summary, nil
}