from typing import List, Literal, Union
from pydantic import BaseModel, Field


# --- Schemas for Weekly Trends ---
class AnalysisResultSchema(BaseModel):
    """
    Represents the aggregated analysis counts for an entity.
    """

    total_comments: int = 0
    positive_count: int = 0
    neutral_count: int = 0
    negative_count: int = 0


class WeeklyTrendResponseSchema(BaseModel):
    """
    Represents a single trending entity in the weekly results API response.
    """

    entity_id: str = Field(..., alias="_id")
    keyword: str
    thumbnail_url: str | None = None
    analysis: AnalysisResultSchema


class WeeklyTrendListResponse(BaseModel):
    """
    Represents the top-level API response for the weekly trends endpoint.
    """

    data: List[WeeklyTrendResponseSchema]


# --- Schemas for Trend Detail ---
class InterestOverTimePoint(BaseModel):
    """
    Represents a single data point in the interest over time chart.
    """

    date: str
    value: int


class CommentSchema(BaseModel):
    """
    Represents a single representative comment.
    """

    publish_date: str
    text: str
    author: str


class RepresentativeCommentsSchema(BaseModel):
    """
    Holds lists of representative comments for each sentiment.
    """

    positive: List[CommentSchema]
    neutral: List[CommentSchema]
    negative: List[CommentSchema]


class TrendDetailResponseSchema(WeeklyTrendResponseSchema):
    """
    Represents the full detailed response for a single entity,
    inheriting basic fields from WeeklyTrendResponseSchema.
    """

    representative_video_url: str | None = None
    interest_over_time: List[InterestOverTimePoint]
    representative_comments: RepresentativeCommentsSchema


# --- Schemas for On-Demand Analysis ---
class OnDemandRequestSchema(BaseModel):
    """
    Defines the request body for an on-demand analysis request from a user.
    """

    keyword: str


# Define two distinct response schemas
class QueuedResponseSchema(BaseModel):
    """
    Response when a new job is successfully queued.
    """

    status: Literal["queued"]
    job_id: str


class FoundResponseSchema(BaseModel):
    """
    Response when an existing analysis is found.
    """

    status: Literal["found"]
    entity_id: str


# The final response model is a Union of the two possibilities
OnDemandResponseSchema = Union[QueuedResponseSchema, FoundResponseSchema]


class JobStatusResponseSchema(BaseModel):
    """
    Represents the status of an on-demand job.
    """

    job_id: str = Field(..., alias="_id")
    status: str
    keyword: str
    result: TrendDetailResponseSchema | None = None
    error_message: str | None = None  # To send error messages to the frontend