from __future__ import annotations

from dataclasses import dataclass, field
from typing import Any


@dataclass
class Vulnerability:
    id: str
    package_name: str
    current_version: str
    severity: str
    title: str
    description: str
    affected_versions: list[str]
    fixed_version: str | None
    published: str
    modified: str
    cvss_score: float | None = None
    cwe: list[str] = field(default_factory=list)
    references: list[str] = field(default_factory=list)
    source: str = "unknown"

    def to_dict(self) -> dict[str, Any]:
        return {
            "id": self.id,
            "package_name": self.package_name,
            "current_version": self.current_version,
            "severity": self.severity,
            "title": self.title,
            "description": self.description,
            "affected_versions": self.affected_versions,
            "fixed_version": self.fixed_version,
            "published": self.published,
            "modified": self.modified,
            "cvss_score": self.cvss_score,
            "cwe": self.cwe,
            "references": self.references,
            "source": self.source,
        }

    @classmethod
    def from_osv(cls, data: dict[str, Any], package_name: str, current_version: str) -> "Vulnerability":
        affected = data.get("affected", [])
        versions = []
        fixed_version = None

        if affected:
            pkg = affected[0]
            ranges = pkg.get("ranges", [])
            for range_info in ranges:
                if range_info.get("type") == "SEMVER":
                    for event in range_info.get("events", []):
                        if event.get("type") == "introduced":
                            versions.append(event.get("value", ""))
                        elif event.get("type") == "fixed":
                            fixed_version = event.get("value")

        severity = "medium"
        cvss = None
        for severity_info in data.get("severity", []):
            if severity_info.get("type") == "CVSS_V3":
                cvss = float(severity_info.get("score", 0))
                if cvss >= 9.0:
                    severity = "critical"
                elif cvss >= 7.0:
                    severity = "high"
                elif cvss >= 4.0:
                    severity = "medium"
                else:
                    severity = "low"
                break

        return cls(
            id=data.get("id", ""),
            package_name=package_name,
            current_version=current_version,
            severity=severity,
            title=data.get("summary", ""),
            description=data.get("details", ""),
            affected_versions=versions,
            fixed_version=fixed_version,
            published=data.get("published", ""),
            modified=data.get("modified", ""),
            cvss_score=cvss,
            cwe=data.get("cwe", []),
            references=[ref.get("url", "") for ref in data.get("references", [])],
            source="OSV",
        )