import os
from typing import List, Optional

import cohere

from semantic_router.encoders import BaseEncoder


class CohereEncoder(BaseEncoder):
    client: Optional[cohere.Client] = None
    type: str = "cohere"
    input_type: Optional[str] = "search_query"

    def __init__(
        self,
        name: Optional[str] = None,
        cohere_api_key: Optional[str] = None,
        score_threshold: float = 0.3,
        input_type: Optional[str] = "search_query",
    ):
        if name is None:
            name = os.getenv("COHERE_MODEL_NAME", "embed-english-v3.0")
        super().__init__(
            name=name,
            score_threshold=score_threshold,
            input_type=input_type,  # type: ignore
        )
        self.input_type = input_type
        cohere_api_key = cohere_api_key or os.getenv("COHERE_API_KEY")
        if cohere_api_key is None:
            raise ValueError("Cohere API key cannot be 'None'.")
        try:
            self.client = cohere.Client(cohere_api_key)
        except Exception as e:
            raise ValueError(
                f"Cohere API client failed to initialize. Error: {e}"
            ) from e

    def __call__(self, docs: List[str]) -> List[List[float]]:
        if self.client is None:
            raise ValueError("Cohere client is not initialized.")
        try:
            embeds = self.client.embed(
                docs, input_type=self.input_type, model=self.name
            )
            return embeds.embeddings
        except Exception as e:
            raise ValueError(f"Cohere API call failed. Error: {e}") from e
