from datetime import datetime
from typing import Optional, List, Dict, Any, Generic, TypeVar
from pydantic import BaseModel
from uuid import UUID

T = TypeVar("T")


# Pagination schemas
class PaginationMeta(BaseModel):
    page: int
    limit: int
    total: int
    total_pages: int


class PaginatedResponse(BaseModel, Generic[T]):
    items: List[T]
    pagination: PaginationMeta


# Project schemas
class ProjectCreate(BaseModel):
    name: str
    description: Optional[str] = None
    is_public: bool = True


class ProjectResponse(BaseModel):
    id: UUID
    name: str
    description: Optional[str]
    is_public: bool
    created_at: datetime
    updated_at: datetime
    created_by: str

    class Config:
        from_attributes = True


# Package format and platform enums
PACKAGE_FORMATS = ["generic", "npm", "pypi", "docker", "deb", "rpm", "maven", "nuget", "helm"]
PACKAGE_PLATFORMS = ["any", "linux", "darwin", "windows", "linux-amd64", "linux-arm64", "darwin-amd64", "darwin-arm64", "windows-amd64"]


# Package schemas
class PackageCreate(BaseModel):
    name: str
    description: Optional[str] = None
    format: str = "generic"
    platform: str = "any"


class PackageResponse(BaseModel):
    id: UUID
    project_id: UUID
    name: str
    description: Optional[str]
    format: str
    platform: str
    created_at: datetime
    updated_at: datetime

    class Config:
        from_attributes = True


class TagSummary(BaseModel):
    """Lightweight tag info for embedding in package responses"""
    name: str
    artifact_id: str
    created_at: datetime


class PackageDetailResponse(BaseModel):
    """Package with aggregated metadata"""
    id: UUID
    project_id: UUID
    name: str
    description: Optional[str]
    format: str
    platform: str
    created_at: datetime
    updated_at: datetime
    # Aggregated fields
    tag_count: int = 0
    artifact_count: int = 0
    total_size: int = 0
    latest_tag: Optional[str] = None
    latest_upload_at: Optional[datetime] = None
    # Recent tags (limit 5)
    recent_tags: List[TagSummary] = []

    class Config:
        from_attributes = True


# Artifact schemas
class ArtifactResponse(BaseModel):
    id: str
    size: int
    content_type: Optional[str]
    original_name: Optional[str]
    created_at: datetime
    created_by: str
    ref_count: int
    format_metadata: Optional[Dict[str, Any]] = None

    class Config:
        from_attributes = True


# Tag schemas
class TagCreate(BaseModel):
    name: str
    artifact_id: str


class TagResponse(BaseModel):
    id: UUID
    package_id: UUID
    name: str
    artifact_id: str
    created_at: datetime
    created_by: str

    class Config:
        from_attributes = True


# Upload response
class UploadResponse(BaseModel):
    artifact_id: str
    size: int
    project: str
    package: str
    tag: Optional[str]
    format_metadata: Optional[Dict[str, Any]] = None
    deduplicated: bool = False


# Resumable upload schemas
class ResumableUploadInitRequest(BaseModel):
    """Request to initiate a resumable upload"""
    expected_hash: str  # SHA256 hash of the file (client must compute)
    filename: str
    content_type: Optional[str] = None
    size: int
    tag: Optional[str] = None


class ResumableUploadInitResponse(BaseModel):
    """Response from initiating a resumable upload"""
    upload_id: Optional[str]  # None if file already exists
    already_exists: bool
    artifact_id: Optional[str] = None  # Set if already_exists is True
    chunk_size: int  # Recommended chunk size for parts


class ResumableUploadPartResponse(BaseModel):
    """Response from uploading a part"""
    part_number: int
    etag: str


class ResumableUploadCompleteRequest(BaseModel):
    """Request to complete a resumable upload"""
    tag: Optional[str] = None


class ResumableUploadCompleteResponse(BaseModel):
    """Response from completing a resumable upload"""
    artifact_id: str
    size: int
    project: str
    package: str
    tag: Optional[str]


class ResumableUploadStatusResponse(BaseModel):
    """Status of a resumable upload"""
    upload_id: str
    uploaded_parts: List[int]
    total_uploaded_bytes: int


# Consumer schemas
class ConsumerResponse(BaseModel):
    id: UUID
    package_id: UUID
    project_url: str
    last_access: datetime
    created_at: datetime

    class Config:
        from_attributes = True


# Health check
class HealthResponse(BaseModel):
    status: str
    version: str = "1.0.0"