from pathlib import Path

from app.modules.editor.domain.entities import AffectedFile, EditableFile, ImpactResult
from app.modules.editor.infrastructure.file_io import read_file, write_file
from app.modules.project.domain.entities import Project
from app.modules.scanner.application.services import ScanService
from app.modules.scanner.domain.entities import ScanResult


class EditorService:
    def __init__(self, scan_service: ScanService) -> None:
        self._scan_service = scan_service

    def get_file(self, project: Project, relative_path: str) -> EditableFile:
        return read_file(Path(project.design_dir), relative_path)

    def save_file(self, project: Project, relative_path: str, content: str) -> ScanResult:
        write_file(Path(project.design_dir), relative_path, content)
        return self._scan_service.scan(project)

    def get_impact(
        self, project: Project, relative_path: str, scan_result: ScanResult,
    ) -> ImpactResult:
        """Walk DesignDocument.downstream + TraceabilityLink to find affected files."""
        affected: list[AffectedFile] = []

        # Find DesignDocument for this file
        for doc in scan_result.design_documents:
            if doc.file_path == relative_path or relative_path.endswith(doc.file_path):
                for downstream in doc.downstream:
                    affected.append(
                        AffectedFile(path=downstream, reason=f"downstream of {doc.doc_id}")
                    )

        return ImpactResult(source_file=relative_path, affected_files=affected)