from datetime import datetime
from typing import Literal

from pydantic import field_serializer

from fields.base import ResponseModel
from libs.helper import to_timestamp

# Mirrors models.enums.SegmentStatus / SegmentType; response schemas do not import models.
SegmentStatus = Literal["waiting", "indexing", "completed", "error", "paused", "re_segment"]
SegmentType = Literal["automatic", "customized"]


class SegmentAttachmentResponse(ResponseModel):
    id: str
    name: str
    size: int
    extension: str
    mime_type: str | None
    source_url: str


class ChildChunkResponse(ResponseModel):
    id: str
    segment_id: str
    content: str
    position: int
    word_count: int
    type: SegmentType
    created_at: datetime | int
    updated_at: datetime | int

    @field_serializer("created_at", "updated_at")
    def serialize_timestamp(self, value: datetime | int) -> int:
        return to_timestamp(value)


class SegmentResponse(ResponseModel):
    id: str
    position: int
    document_id: str
    content: str
    sign_content: str
    answer: str | None
    word_count: int
    tokens: int
    keywords: list[str] | None
    index_node_id: str | None
    index_node_hash: str | None
    hit_count: int
    enabled: bool
    disabled_at: datetime | int | None
    disabled_by: str | None
    status: SegmentStatus
    created_by: str
    created_at: datetime | int
    updated_at: datetime | int
    updated_by: str | None
    indexing_at: datetime | int | None
    completed_at: datetime | int | None
    error: str | None
    stopped_at: datetime | int | None
    child_chunks: list[ChildChunkResponse]
    attachments: list[SegmentAttachmentResponse]
    summary: str | None

    @field_serializer("created_at", "updated_at")
    def serialize_required_timestamp(self, value: datetime | int) -> int:
        return to_timestamp(value)

    @field_serializer("disabled_at", "indexing_at", "completed_at", "stopped_at")
    def serialize_optional_timestamp(self, value: datetime | int | None) -> int | None:
        return to_timestamp(value)


class SegmentDetailResponse(ResponseModel):
    data: SegmentResponse
    doc_form: str


class ChildChunkDetailResponse(ResponseModel):
    data: ChildChunkResponse


class ChildChunkListResponse(ResponseModel):
    data: list[ChildChunkResponse]
    total: int
    total_pages: int
    page: int
    limit: int