from pydantic import BaseModel, Field, field_validator
from typing import List, Optional, Union, Dict, Any, Tuple
import os


# ==================== Request Models ====================
class GeneralRequest(BaseModel):
    text: Optional[str] = None
    texts: Optional[List[str]] = None
    entities: List[str]
    prompt: Optional[str] = None
    threshold: Optional[float] = Field(default=0.5, ge=0.0, le=1.0)

    @field_validator('entities')
    @classmethod
    def validate_entities(cls, v):
        if not v or len(v) == 0:
            raise ValueError("entities list cannot be empty")
        return v

    @field_validator('text', 'texts')
    @classmethod
    def validate_text_length(cls, v):
        max_length = int(os.getenv("MAX_TEXT_LENGTH", "10000"))
        if isinstance(v, str) and len(v) > max_length:
            raise ValueError(f"text exceeds maximum length of {max_length}")
        if isinstance(v, list):
            for text in v:
                if len(text) > max_length:
                    raise ValueError(f"text exceeds maximum length of {max_length}")
        return v


class RelationRule(BaseModel):
    relation: str
    pairs_filter: List[Tuple[str, str]]
    distance: int


class RelationExtractionRequest(BaseModel):
    text: Optional[str] = None
    texts: Optional[List[str]] = None
    relations: List[str]
    entities: Optional[List[str]] = None
    rules: Optional[List[RelationRule]] = None
    prompt: Optional[str] = None
    threshold: Optional[float] = Field(default=0.5, ge=0.0, le=1.0)

    @field_validator('relations')
    @classmethod
    def validate_relations(cls, v):
        if not v or len(v) == 0:
            raise ValueError("relations list cannot be empty")
        return v

    @field_validator('text', 'texts')
    @classmethod
    def validate_text_length(cls, v):
        max_length = int(os.getenv("MAX_TEXT_LENGTH", "10000"))
        if isinstance(v, str) and len(v) > max_length:
            raise ValueError(f"text exceeds maximum length of {max_length}")
        if isinstance(v, list):
            for text in v:
                if len(text) > max_length:
                    raise ValueError(f"text exceeds maximum length of {max_length}")
        return v


class SummarizationRequest(BaseModel):
    text: Optional[str] = None
    texts: Optional[List[str]] = None
    prompt: Optional[str] = None
    threshold: Optional[float] = Field(default=0.5, ge=0.0, le=1.0)

    @field_validator('text', 'texts')
    @classmethod
    def validate_text_length(cls, v):
        max_length = int(os.getenv("MAX_TEXT_LENGTH", "10000"))
        if isinstance(v, str) and len(v) > max_length:
            raise ValueError(f"text exceeds maximum length of {max_length}")
        if isinstance(v, list):
            for text in v:
                if len(text) > max_length:
                    raise ValueError(f"text exceeds maximum length of {max_length}")
        return v


# ==================== Response Models ====================
class EntityOutput(BaseModel):
    entity: str
    span: str
    start: int
    end: int
    score: float


class RelationOutput(BaseModel):
    source: EntityOutput
    relation: str
    target: EntityOutput
    score: float


class SummaryOutput(BaseModel):
    text: str
    start: int
    end: int
    score: float

# ==================== Error Response Model ====================
class ErrorDetail(BaseModel):
    code: str
    message: str
    details: Dict[str, Any] = Field(default_factory=dict)


class ErrorResponse(BaseModel):
    error: ErrorDetail