"""
Data Import REST API endpoint for VitalGraph.

This module provides REST API endpoints for managing data import jobs using JSON format.
Handles import job lifecycle and file uploads for import data.
"""

from typing import Dict, List, Optional, Any
from fastapi import APIRouter, Query, Depends, UploadFile, File, Path
from pydantic import BaseModel, Field
from datetime import datetime
from enum import Enum

from ..model.import_model import (
    ImportStatus,
    ImportType,
    ImportJob,
    ImportJobsResponse,
    ImportJobResponse,
    ImportCreateResponse,
    ImportUpdateResponse,
    ImportDeleteResponse,
    ImportExecuteResponse,
    ImportStatusResponse,
    ImportLogResponse,
    ImportUploadResponse
)


class ImportEndpoint:
    """Data Import endpoint handler."""
    
    def __init__(self, space_manager, auth_dependency):
        self.space_manager = space_manager
        self.auth_dependency = auth_dependency
        self.router = APIRouter()
        self._setup_routes()
    
    def _setup_routes(self):
        """Setup FastAPI routes for data import management."""
        
        @self.router.post("/import", response_model=ImportCreateResponse)
        async def create_import_job(
            request: ImportJob,
            current_user: Dict = Depends(self.auth_dependency)
        ):
            """Create new data import job."""
            return await self._create_import_job(request, current_user)
        
        @self.router.get("/import", response_model=ImportJobsResponse)
        async def list_import_jobs(
            space_id: Optional[str] = Query(None, description="Filter by space ID"),
            graph_id: Optional[str] = Query(None, description="Filter by graph ID"),
            page_size: int = Query(100, ge=1, le=1000, description="Number of jobs per page"),
            offset: int = Query(0, ge=0, description="Offset for pagination"),
            current_user: Dict = Depends(self.auth_dependency)
        ):
            """List all import jobs with optional filtering."""
            return await self._list_import_jobs(space_id, graph_id, page_size, offset, current_user)
        
        @self.router.get("/import/{import_id}", response_model=ImportJobResponse)
        async def get_import_job(
            import_id: str = Path(..., description="Import job ID"),
            current_user: Dict = Depends(self.auth_dependency)
        ):
            """Get import job details by ID."""
            return await self._get_import_job(import_id, current_user)
        
        @self.router.put("/import/{import_id}", response_model=ImportUpdateResponse)
        async def update_import_job(
            request: ImportJob,
            import_id: str = Path(..., description="Import job ID"),
            current_user: Dict = Depends(self.auth_dependency)
        ):
            """Update import job."""
            return await self._update_import_job(import_id, request, current_user)
        
        @self.router.delete("/import/{import_id}", response_model=ImportDeleteResponse)
        async def delete_import_job(
            import_id: str = Path(..., description="Import job ID"),
            current_user: Dict = Depends(self.auth_dependency)
        ):
            """Delete import job."""
            return await self._delete_import_job(import_id, current_user)
        
        @self.router.post("/import/{import_id}/execute", response_model=ImportExecuteResponse)
        async def execute_import_job(
            import_id: str = Path(..., description="Import job ID"),
            current_user: Dict = Depends(self.auth_dependency)
        ):
            """Execute import job."""
            return await self._execute_import_job(import_id, current_user)
        
        @self.router.get("/import/{import_id}/status", response_model=ImportStatusResponse)
        async def get_import_status(
            import_id: str = Path(..., description="Import job ID"),
            current_user: Dict = Depends(self.auth_dependency)
        ):
            """Get import execution status."""
            return await self._get_import_status(import_id, current_user)
        
        @self.router.get("/import/{import_id}/log", response_model=ImportLogResponse)
        async def get_import_log(
            import_id: str = Path(..., description="Import job ID"),
            current_user: Dict = Depends(self.auth_dependency)
        ):
            """Get import execution log."""
            return await self._get_import_log(import_id, current_user)
        
        @self.router.post("/import/{import_id}/upload", response_model=ImportUploadResponse)
        async def upload_import_file(
            import_id: str = Path(..., description="Import job ID"),
            file: UploadFile = File(..., description="File to upload for import"),
            current_user: Dict = Depends(self.auth_dependency)
        ):
            """Upload file to import job."""
            return await self._upload_import_file(import_id, file, current_user)
    
    async def _create_import_job(self, request: ImportJob, current_user: Dict) -> ImportCreateResponse:
        """Create new import job."""
        # NO-OP implementation - simulate import job creation
        import uuid
        
        import_id = str(uuid.uuid4())
        now = datetime.utcnow()
        
        import_job = ImportJob(
            import_id=import_id,
            name=request.name,
            description=request.description,
            import_type=request.import_type,
            space_id=request.space_id,
            graph_id=request.graph_id,
            status=ImportStatus.CREATED,
            created_date=now,
            updated_date=now,
            progress_percent=0.0,
            records_processed=0,
            config=request.config or {},
            uploaded_files=[]
        )
        
        return ImportCreateResponse(
            message="Successfully created import job",
            import_id=import_id,
            import_job=import_job
        )
    
    async def _list_import_jobs(self, space_id: Optional[str], graph_id: Optional[str], page_size: int, offset: int, current_user: Dict) -> ImportJobsResponse:
        """List import jobs with filtering."""
        # NO-OP implementation - return sample import jobs
        sample_jobs = [
            ImportJob(
                import_id="import_001",
                name="RDF Data Import",
                description="Import RDF turtle data from external source",
                import_type=ImportType.RDF_TURTLE,
                space_id="space_001",
                graph_id="graph_001",
                status=ImportStatus.COMPLETED,
                created_date=datetime(2024, 1, 15, 10, 30, 0),
                updated_date=datetime(2024, 1, 15, 11, 0, 0),
                started_date=datetime(2024, 1, 15, 10, 35, 0),
                completed_date=datetime(2024, 1, 15, 11, 0, 0),
                progress_percent=100.0,
                records_processed=1500,
                records_total=1500,
                uploaded_files=["data.ttl"]
            ),
            ImportJob(
                import_id="import_002",
                name="CSV Entity Import",
                description="Import entity data from CSV file",
                import_type=ImportType.CSV,
                space_id="space_001",
                graph_id="graph_002",
                status=ImportStatus.RUNNING,
                created_date=datetime(2024, 1, 16, 9, 0, 0),
                updated_date=datetime(2024, 1, 16, 9, 30, 0),
                started_date=datetime(2024, 1, 16, 9, 15, 0),
                progress_percent=65.0,
                records_processed=650,
                records_total=1000,
                uploaded_files=["entities.csv"]
            ),
            ImportJob(
                import_id="import_003",
                name="JSON-LD Import",
                description="Import structured data in JSON-LD format",
                import_type=ImportType.JSON_LD,
                space_id="space_002",
                status=ImportStatus.CREATED,
                created_date=datetime(2024, 1, 17, 14, 0, 0),
                updated_date=datetime(2024, 1, 17, 14, 0, 0),
                progress_percent=0.0,
                records_processed=0,
                uploaded_files=[]
            )
        ]
        
        # Filter by space_id if provided
        if space_id:
            sample_jobs = [job for job in sample_jobs if job.space_id == space_id]
        
        # Filter by graph_id if provided
        if graph_id:
            sample_jobs = [job for job in sample_jobs if job.graph_id == graph_id]
        
        return ImportJobsResponse(
            import_jobs=sample_jobs,
            total_count=len(sample_jobs),
            page_size=page_size,
            offset=offset
        )
    
    async def _get_import_job(self, import_id: str, current_user: Dict) -> ImportJobResponse:
        """Get import job by ID."""
        # NO-OP implementation - return sample import job
        import_job = ImportJob(
            import_id=import_id,
            name="Sample Import Job",
            description="Sample import job for demonstration",
            import_type=ImportType.RDF_TURTLE,
            space_id="space_001",
            graph_id="graph_001",
            status=ImportStatus.COMPLETED,
            created_date=datetime(2024, 1, 15, 10, 30, 0),
            updated_date=datetime(2024, 1, 15, 11, 0, 0),
            started_date=datetime(2024, 1, 15, 10, 35, 0),
            completed_date=datetime(2024, 1, 15, 11, 0, 0),
            progress_percent=100.0,
            records_processed=1500,
            records_total=1500,
            config={"delimiter": ",", "encoding": "utf-8"},
            uploaded_files=["data.ttl"]
        )
        
        return ImportJobResponse(import_job=import_job)
    
    async def _update_import_job(self, import_id: str, request: ImportJob, current_user: Dict) -> ImportUpdateResponse:
        """Update import job."""
        # NO-OP implementation - simulate import job update
        updated_job = ImportJob(
            import_id=import_id,
            name=request.name,
            description=request.description,
            import_type=request.import_type,
            space_id=request.space_id,
            graph_id=request.graph_id,
            status=request.status or ImportStatus.CREATED,
            created_date=datetime(2024, 1, 15, 10, 30, 0),
            updated_date=datetime.utcnow(),
            progress_percent=request.progress_percent or 0.0,
            records_processed=request.records_processed or 0,
            records_total=request.records_total,
            config=request.config,
            uploaded_files=request.uploaded_files or []
        )
        
        return ImportUpdateResponse(
            message="Successfully updated import job",
            import_job=updated_job
        )
    
    async def _delete_import_job(self, import_id: str, current_user: Dict) -> ImportDeleteResponse:
        """Delete import job."""
        # NO-OP implementation - simulate import job deletion
        return ImportDeleteResponse(
            message="Successfully deleted import job",
            import_id=import_id
        )
    
    async def _execute_import_job(self, import_id: str, current_user: Dict) -> ImportExecuteResponse:
        """Execute import job."""
        # NO-OP implementation - simulate import job execution
        return ImportExecuteResponse(
            message="Successfully started import job execution",
            import_id=import_id,
            execution_started=True
        )
    
    async def _get_import_status(self, import_id: str, current_user: Dict) -> ImportStatusResponse:
        """Get import execution status."""
        # NO-OP implementation - return sample status
        return ImportStatusResponse(
            import_id=import_id,
            status=ImportStatus.RUNNING,
            progress_percent=75.0,
            records_processed=750,
            records_total=1000,
            started_date=datetime(2024, 1, 16, 9, 15, 0),
            completed_date=None,
            error_message=None
        )
    
    async def _get_import_log(self, import_id: str, current_user: Dict) -> ImportLogResponse:
        """Get import execution log."""
        # NO-OP implementation - return sample log entries
        log_entries = [
            {
                "timestamp": "2024-01-16T09:15:00Z",
                "level": "INFO",
                "message": "Import job started",
                "details": {"records_total": 1000}
            },
            {
                "timestamp": "2024-01-16T09:20:00Z",
                "level": "INFO",
                "message": "Processing batch 1",
                "details": {"batch_size": 100, "records_processed": 100}
            },
            {
                "timestamp": "2024-01-16T09:25:00Z",
                "level": "WARNING",
                "message": "Skipped invalid record",
                "details": {"record_id": "rec_123", "reason": "missing required field"}
            },
            {
                "timestamp": "2024-01-16T09:30:00Z",
                "level": "INFO",
                "message": "Processing batch 7",
                "details": {"batch_size": 100, "records_processed": 700}
            }
        ]
        
        return ImportLogResponse(
            import_id=import_id,
            log_entries=log_entries,
            total_entries=len(log_entries)
        )
    
    async def _upload_import_file(self, import_id: str, file: UploadFile, current_user: Dict) -> ImportUploadResponse:
        """Upload file to import job."""
        # NO-OP implementation - simulate file upload
        
        # Read file content (in real implementation, this would be stored)
        content = await file.read()
        file_size = len(content)
        
        # In real implementation, would:
        # 1. Validate that import job exists
        # 2. Store file content in file storage system
        # 3. Update import job with uploaded file info
        # 4. Validate file format matches import type
        # 5. Create audit trail
        
        return ImportUploadResponse(
            message="Successfully uploaded file to import job",
            import_id=import_id,
            filename=file.filename or "unknown",
            file_size=file_size
        )


def create_import_router(space_manager, auth_dependency) -> APIRouter:
    """Create and return the data import router."""
    endpoint = ImportEndpoint(space_manager, auth_dependency)
    return endpoint.router
