"""
CLI command for the markitect helper.
"""

import os
import sys

import click

from markitect.helper.knowledge import collect_knowledge

DEFAULT_PROVIDER = "openrouter"
DEFAULT_MODEL = "openrouter/aurora-alpha"
MODEL_ENV_VAR = "MARKITECT_HELPER_MODEL"

SYSTEM_PROMPT_TEMPLATE = (
    "You are a MarkiTect expert assistant. Answer the user's question "
    "based on the following MarkiTect documentation. Be concise and "
    "accurate. If the documentation does not cover the question, say so.\n\n"
    "{knowledge}"
)


@click.command("helper")
@click.argument("question", nargs=-1, required=True)
@click.option(
    "--provider", "-p",
    default=DEFAULT_PROVIDER,
    type=click.Choice(["openrouter", "claude-code", "gemini", "openai"]),
    show_default=True,
    help="LLM provider to use.",
)
@click.option(
    "--model", "-m",
    default=None,
    help=(
        f"Model name. Overrides {MODEL_ENV_VAR} env var and the default "
        f"({DEFAULT_MODEL})."
    ),
)
def helper_command(question, provider, model):
    """Ask a question about MarkiTect and get an answer from the docs.

    \b
    Examples:
        markitect helper "What is markitect?"
        markitect helper How do schemas work
        markitect helper -m anthropic/claude-sonnet-4 "Explain templates"
    """
    from markitect.llm import create_adapter
    from markitect.llm.exceptions import LLMConfigurationError, LLMError
    from markitect.prompts.execution.models import RunConfig

    # Join multi-word question into a single string.
    question_text = " ".join(question)
    if not question_text.strip():
        click.echo("Error: empty question.", err=True)
        sys.exit(1)

    # Resolve model: --model flag > env var > default.
    resolved_model = model or os.environ.get(MODEL_ENV_VAR) or DEFAULT_MODEL

    # Build knowledge context.
    click.echo("Loading markitect knowledge base...", err=True)
    knowledge = collect_knowledge()
    if not knowledge:
        click.echo("Warning: no documentation files found.", err=True)

    system_prompt = SYSTEM_PROMPT_TEMPLATE.format(knowledge=knowledge)

    # Create adapter.
    try:
        adapter = create_adapter(
            provider=provider,
            model=resolved_model,
            system_prompt=system_prompt,
        )
    except LLMConfigurationError as exc:
        click.echo(f"Configuration error: {exc}", err=True)
        if "api" in str(exc).lower() or "key" in str(exc).lower():
            click.echo(
                "Hint: set OPENROUTER_API_KEY (or the relevant provider key) "
                "in your environment.",
                err=True,
            )
        sys.exit(1)

    # Execute the question.
    click.echo(f"Asking {provider} ({resolved_model})...", err=True)
    try:
        config = RunConfig(
            model_name=resolved_model,
            max_tokens=4000,
            temperature=0.3,
        )
        response = adapter.execute_prompt(question_text, config)
    except LLMError as exc:
        click.echo(f"LLM error: {exc}", err=True)
        sys.exit(1)

    click.echo(response.content)