from __future__ import annotations

import logging

logger = logging.getLogger(__name__)


class ILinkStreaming:
    streaming_mode = "block"
    ENABLED = True
    MIN_CHARS = 200
    MAX_CHARS = 1200
    COALESCE_MIN_CHARS = 80
    COALESCE_MAX_CHARS = 400
    COALESCE_IDLE_MS = 500
    MAX_BLOCKS = 5
    FINISH_MARK = "[↓]"

    @classmethod
    def create_block_chunker(cls) -> dict:
        return {
            "mode": "length",
            "min_chars": cls.MIN_CHARS,
            "max_chars": cls.MAX_CHARS,
            "coalesce_min_chars": cls.COALESCE_MIN_CHARS,
            "coalesce_max_chars": cls.COALESCE_MAX_CHARS,
            "coalesce_idle_ms": cls.COALESCE_IDLE_MS,
        }

    @classmethod
    def should_stream(cls, estimated_length: int) -> bool:
        return estimated_length > cls.MIN_CHARS

    @classmethod
    def build_chunk(cls, text: str, is_final: bool) -> str:
        if is_final:
            return text
        return f"{text}\n{cls.FINISH_MARK}"