from __future__ import annotations

from dataclasses import dataclass, field
from typing import Any, Protocol


@dataclass(slots=True)
class FieldEvidence:
    field_name: str
    method: str
    confidence: float
    evidence: str = ""


@dataclass(slots=True)
class ExtractedJob:
    url: str
    title: str
    employer_name: str = ""
    external_id: str = ""
    location_text: str = ""
    region: str = ""
    postal_code: str = ""
    country: str = ""
    description_html: str = ""
    description_text: str = ""
    language: str = ""
    date_posted: str = ""
    valid_through: str = ""
    employment_types: list[str] = field(default_factory=list)
    workplace_type: str = ""
    compensation: dict[str, Any] = field(default_factory=dict)
    skills_required: list[str] = field(default_factory=list)
    skills_preferred: list[str] = field(default_factory=list)
    raw: dict[str, Any] = field(default_factory=dict)
    evidence: list[FieldEvidence] = field(default_factory=list)


@dataclass(slots=True)
class ExtractionResult:
    jobs: list[ExtractedJob]
    parser_key: str
    parser_version: str
    confidence: float
    warnings: list[str] = field(default_factory=list)


class SourceAdapter(Protocol):
    parser_key: str
    parser_version: str

    def extract(self, content: str, *, url: str) -> ExtractionResult: ...