#!/usr/bin/env python3
# [20250120_DOCS] Safety Parser module documentation

from __future__ import annotations

from dataclasses import dataclass, field
from pathlib import Path


@dataclass
class CVSSScore:
    """CVSS (Common Vulnerability Scoring System) score."""

    version: str  # "2.0" or "3.1"
    base_score: float
    impact_score: float | None = None
    exploitability_score: float | None = None

    @property
    def severity(self) -> str:
        """Get severity level based on CVSS score."""
        # CVSS v3.1 scale
        if self.base_score >= 9.0:
            return "CRITICAL"
        elif self.base_score >= 7.0:
            return "HIGH"
        elif self.base_score >= 4.0:
            return "MEDIUM"
        elif self.base_score > 0:
            return "LOW"
        return "NONE"


@dataclass
class Vulnerability:
    """Represents a security vulnerability."""

    cve_id: str
    package_name: str
    advisory: str
    affected_versions: list[str] = field(default_factory=list)
    fixed_versions: list[str] = field(default_factory=list)
    published_date: str | None = None
    cvss_v2: CVSSScore | None = None
    cvss_v3: CVSSScore | None = None
    safety_id: str | None = None
    more_info_url: str | None = None

    @property
    def severity(self) -> str:
        """Get severity from CVSS score."""
        if self.cvss_v3:
            return self.cvss_v3.severity
        if self.cvss_v2:
            return self.cvss_v2.severity
        return "UNKNOWN"


@dataclass
class DependencyVulnerability:
    """Represents a vulnerable dependency."""

    package_name: str
    current_version: str
    vulnerabilities: list[Vulnerability] = field(default_factory=list)
    is_transitive: bool = False
    parent_package: str | None = None

    @property
    def total_vulnerabilities(self) -> int:
        """Count total vulnerabilities for this dependency."""
        return len(self.vulnerabilities)

    @property
    def highest_severity(self) -> str:
        """Get highest severity among vulnerabilities."""
        severities = {"CRITICAL": 4, "HIGH": 3, "MEDIUM": 2, "LOW": 1, "NONE": 0}
        if not self.vulnerabilities:
            return "NONE"

        highest = max((severities.get(v.severity, 0), v.severity) for v in self.vulnerabilities)
        return highest[1]


@dataclass
class SafetyConfig:
    """Configuration for Safety parser."""

    api_key: str | None = None
    database: str | None = None  # Path to custom vulnerability database
    ignore_ids: list[str] = field(default_factory=list)  # CVE IDs to ignore

    @classmethod
    def from_policy_file(cls, policy_path: str | Path) -> SafetyConfig:
        """Load configuration from .safety-policy.json."""
        return cls()


@dataclass
class SafetyReport:
    """Results from Safety vulnerability analysis."""

    file_path: str | None = None
    vulnerabilities: list[DependencyVulnerability] = field(default_factory=list)
    scanned_dependencies: int = 0
    error: str | None = None
    database_version: str | None = None

    @property
    def total_vulnerabilities(self) -> int:
        """Total count of vulnerabilities found."""
        return sum(dep.total_vulnerabilities for dep in self.vulnerabilities)

    @property
    def has_critical(self) -> bool:
        """Check if any critical vulnerabilities exist."""
        return any(dep.highest_severity == "CRITICAL" for dep in self.vulnerabilities)

    @property
    def vulnerable_packages(self) -> list[str]:
        """Get list of packages with vulnerabilities."""
        return [dep.package_name for dep in self.vulnerabilities]


class SafetyParser:
    """
    Parser for dependency security vulnerabilities using Safety.

    STATUS: NOT IMPLEMENTED
    PRIORITY: P2 - HIGH
    """

    def __init__(self, config: SafetyConfig | None = None):
        """
        Initialize Safety parser.

        Args:
            config: SafetyConfig instance or None to use defaults
        """
        self.config = config or SafetyConfig()

    def analyze_requirements_file(self, requirements_path: str | Path) -> SafetyReport:
        """
        Check requirements.txt file for vulnerabilities.

        Args:
            requirements_path: Path to requirements.txt

        Returns:
            SafetyReport with vulnerability findings

        """
        raise NotImplementedError("SafetyParser.analyze_requirements_file() not yet implemented")

    def analyze_lock_file(self, lock_path: str | Path) -> SafetyReport:
        """
        Check lock file (poetry.lock, pipenv.lock) for vulnerabilities.

        Args:
            lock_path: Path to lock file

        Returns:
            SafetyReport with vulnerability findings

        """
        raise NotImplementedError("SafetyParser.analyze_lock_file() not yet implemented")

    def check_package(self, package_name: str, version: str) -> list[Vulnerability]:
        """
        Check specific package version for vulnerabilities.

        Args:
            package_name: Name of package (e.g., "django")
            version: Package version (e.g., "3.0.0")

        Returns:
            List of Vulnerability objects for this package

        """
        raise NotImplementedError("SafetyParser.check_package() not yet implemented")

    def get_remediation(self, vulnerability: Vulnerability) -> str:
        """
        Get remediation steps for a vulnerability.

        Args:
            vulnerability: Vulnerability to remediate

        Returns:
            Remediation steps as string

        """
        raise NotImplementedError("SafetyParser.get_remediation() not yet implemented")
