"""
Pydantic models for request/response validation and serialization.
"""

from pydantic import BaseModel, Field, HttpUrl
from typing import Optional
from datetime import datetime
from enum import Enum


# --- Enums ---

class InspectionStatus(str, Enum):
    RUNNING = "running"
    COMPLETED = "completed"
    ERROR = "error"


class Severity(str, Enum):
    CRITICAL = "critical"
    MAJOR = "major"
    MINOR = "minor"
    INFO = "info"


class CategoryName(str, Enum):
    HTML_CSS = "html_css"
    ACCESSIBILITY = "accessibility"
    SEO = "seo"
    PERFORMANCE_SECURITY = "performance_security"


# --- Request ---

class StartInspectionRequest(BaseModel):
    url: HttpUrl
    accessibility_standard: str = Field(
        default="wcag_2.1_aa",
        description="접근성 검사 표준 (wcag_2.0_a, wcag_2.0_aa, wcag_2.1_aa, wcag_2.2_aa, kwcag_2.1, kwcag_2.2)",
    )


# --- Core Data Models ---

class Issue(BaseModel):
    code: str
    category: str
    severity: Severity
    message: str
    element: Optional[str] = None
    line: Optional[int] = None
    suggestion: str
    wcag_criterion: Optional[str] = None
    # KWCAG mapping fields (populated when standard is kwcag_2.1 or kwcag_2.2)
    kwcag_criterion: Optional[str] = None
    kwcag_name: Optional[str] = None
    kwcag_principle: Optional[str] = None
    kwcag_criteria_all: Optional[list[str]] = None


class CategoryResult(BaseModel):
    score: int = Field(ge=0, le=100)
    grade: str
    total_issues: int
    critical: int = 0
    major: int = 0
    minor: int = 0
    info: int = 0
    issues: list[Issue] = []
    # Category-specific fields
    wcag_level: Optional[str] = None
    meta_info: Optional[dict] = None
    sub_scores: Optional[dict] = None
    metrics: Optional[dict] = None


class IssueSummary(BaseModel):
    total_issues: int
    critical: int
    major: int
    minor: int
    info: int


# --- Response Models ---

class StartInspectionResponse(BaseModel):
    inspection_id: str
    status: str = "running"
    url: str
    stream_url: str


class InspectionResult(BaseModel):
    inspection_id: str
    url: str
    status: InspectionStatus
    created_at: datetime
    completed_at: Optional[datetime] = None
    duration_seconds: Optional[float] = None
    overall_score: int = Field(ge=0, le=100)
    grade: str
    categories: dict[str, CategoryResult]
    summary: IssueSummary
    accessibility_standard: Optional[str] = None


class InspectionResultResponse(BaseModel):
    """Response model for GET /api/inspections/{id} (without nested issues)."""
    inspection_id: str
    url: str
    status: InspectionStatus
    created_at: datetime
    completed_at: Optional[datetime] = None
    duration_seconds: Optional[float] = None
    overall_score: int = Field(ge=0, le=100)
    grade: str
    categories: dict[str, CategoryResult]
    summary: IssueSummary
    accessibility_standard: Optional[str] = None


class IssueListResponse(BaseModel):
    inspection_id: str
    total: int
    filters: dict
    issues: list[Issue]


class InspectionListItem(BaseModel):
    inspection_id: str
    url: str
    created_at: datetime
    overall_score: int
    grade: str
    total_issues: int


class PaginatedResponse(BaseModel):
    items: list[InspectionListItem]
    total: int
    page: int
    limit: int
    total_pages: int


class TrendDataPoint(BaseModel):
    inspection_id: str
    created_at: datetime
    overall_score: int
    html_css: int
    accessibility: int
    seo: int
    performance_security: int


class TrendResponse(BaseModel):
    url: str
    data_points: list[TrendDataPoint]


class HealthResponse(BaseModel):
    status: str
    timestamp: str
    services: dict[str, str]


# --- Utility functions ---

def calculate_grade(score: int) -> str:
    """Calculate letter grade from numeric score."""
    if score >= 90:
        return "A+"
    if score >= 80:
        return "A"
    if score >= 70:
        return "B"
    if score >= 60:
        return "C"
    if score >= 50:
        return "D"
    return "F"


def calculate_overall_score(categories: dict[str, CategoryResult]) -> int:
    """Calculate overall score as simple average of category scores."""
    scores = [cat.score for cat in categories.values()]
    if not scores:
        return 0
    return round(sum(scores) / len(scores))