"""
CLI commands for markitect LLM operations:
llm-helper, llm-catalog, llm-check, llm-default, llm-preference.
"""

import json
import os
import subprocess
import sys
import time

import click
from tabulate import tabulate

from markitect.helper.knowledge import collect_knowledge
from markitect.llm.config import find_project_root, resolve_api_key
from markitect.llm.toml_config import (
    HARDCODED_MODEL,
    HARDCODED_PROVIDER,
    MODEL_ENV_VAR,
    USER_CONFIG_PATH,
    DIR_CONFIG_NAME,
    LLMLayer,
    get_default_layers,
    get_preference_layers,
    resolve_llm,
    _dir_config_path,
    _write_llm_section,
    _clear_llm_section,
)

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}"
)

_PROVIDER_INFO = {
    "openrouter": {
        "default_model": "anthropic/claude-sonnet-4",
        "env_var": "OPENROUTER_API_KEY",
        "key_file": "apikey-openrouter.txt",
        "models": [
            "anthropic/claude-sonnet-4",
            "openrouter/aurora-alpha",
            "qwen/qwen3-coder-next",
        ],
    },
    "claude-code": {
        "default_model": None,
        "env_var": None,
        "key_file": None,
        "models": [],
    },
    "gemini": {
        "default_model": "gemini-2.5-flash",
        "env_var": "GEMINI_API_KEY",
        "key_file": "apikey-geminifree.txt",
        "models": ["gemini-2.5-flash"],
    },
    "openai": {
        "default_model": "gpt-4.1-mini",
        "env_var": "OPENAI_API_KEY",
        "key_file": "apikey-chatgpt.txt",
        "models": ["gpt-4.1-mini"],
    },
}


def _probe_key_status(provider: str, info: dict) -> str:
    """Return a human-readable key status string for a provider."""
    if provider == "claude-code":
        try:
            subprocess.run(
                ["claude", "--version"],
                capture_output=True,
                timeout=5,
            )
            return "ok (claude --version)"
        except (FileNotFoundError, subprocess.TimeoutExpired):
            return "not found (claude CLI)"

    env_var = info["env_var"]
    key_file = info["key_file"]
    root = find_project_root()

    # Check env var first.
    if env_var and os.environ.get(env_var, "").strip():
        return "found (env)"

    # Check key file.
    if key_file and root:
        key_path = root / key_file
        try:
            if key_path.read_text().strip():
                return "found (file)"
        except OSError:
            pass

    return "not found"


# ---------------------------------------------------------------------------
# llm-helper (renamed from helper)
# ---------------------------------------------------------------------------

@click.command("llm-helper")
@click.argument("question", nargs=-1, required=True)
@click.option(
    "--provider", "-p",
    default=None,
    type=click.Choice(["openrouter", "claude-code", "gemini", "openai"]),
    help="LLM provider to use.",
)
@click.option(
    "--model", "-m",
    default=None,
    help="Model name (overrides config chain).",
)
def helper_command(question, provider, model):
    """Ask a question about MarkiTect and get an answer from the docs.

    \b
    Examples:
        markitect llm-helper "What is markitect?"
        markitect llm-helper How do schemas work
        markitect llm-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 provider/model via full config chain.
    resolved = resolve_llm(cli_provider=provider, cli_model=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=resolved.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 {resolved.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)


# ---------------------------------------------------------------------------
# llm-catalog
# ---------------------------------------------------------------------------

@click.command("llm-catalog")
@click.option(
    "--format", "output_format",
    type=click.Choice(["table", "json"]),
    default="table",
    show_default=True,
    help="Output format.",
)
def llm_catalog(output_format):
    """Show all known LLM providers with their default model and key status."""
    rows = []
    for prov, info in _PROVIDER_INFO.items():
        key_status = _probe_key_status(prov, info)
        models = info.get("models", [])
        rows.append({
            "provider": prov,
            "default_model": info["default_model"] or "(none, uses CLI)",
            "models": ", ".join(models) if models else "\u2014",
            "env_var": info["env_var"] or "\u2014",
            "key_file": info["key_file"] or "\u2014",
            "key_status": key_status,
        })

    if output_format == "json":
        click.echo(json.dumps(rows, indent=2))
    else:
        headers = {
            "provider": "Provider",
            "default_model": "Default Model",
            "models": "Known Models",
            "env_var": "API Key Env Var",
            "key_file": "Key File",
            "key_status": "Key Status",
        }
        click.echo(tabulate(rows, headers=headers, tablefmt="simple"))


# ---------------------------------------------------------------------------
# llm-check
# ---------------------------------------------------------------------------

@click.command("llm-check")
@click.option(
    "--provider", "-p",
    default=None,
    type=click.Choice(["openrouter", "claude-code", "gemini", "openai"]),
    help="LLM provider to use.",
)
@click.option(
    "--model", "-m",
    default=None,
    help="Model name (overrides config chain).",
)
def llm_check(provider, model):
    """Send a minimal prompt to verify a provider is reachable and responding."""
    import os

    from markitect.llm import create_adapter
    from markitect.llm.exceptions import (
        LLMAPIError,
        LLMConfigurationError,
        LLMError,
    )
    from markitect.prompts.execution.models import RunConfig

    resolved = resolve_llm(cli_provider=provider, cli_model=model)

    click.echo(
        f"Checking {resolved.provider} ({resolved.model})\n"
        f"  provider from: {resolved.provider_source}\n"
        f"  model from:    {resolved.model_source}"
    )

    # Advisory: OPENROUTER_API_KEY is set but this call won't use it. Common
    # source of "works for me, fails for agents" when the env var holds a
    # stale key that overrides a clean config entry.
    if resolved.provider != "openrouter" and os.environ.get("OPENROUTER_API_KEY"):
        click.echo(
            "  note: OPENROUTER_API_KEY is set but won't be used for this "
            "provider. If OpenRouter calls fail elsewhere with 401, the env "
            "var may be stale — unset or update it.",
            err=True,
        )

    try:
        adapter = create_adapter(
            provider=resolved.provider,
            model=resolved.model,
        )
    except LLMConfigurationError as exc:
        click.echo(f"ERROR \u2014 Configuration: {exc}", err=True)
        sys.exit(1)

    config = RunConfig(
        model_name=resolved.model,
        max_tokens=16,
        temperature=0.0,
    )

    start = time.monotonic()
    try:
        response = adapter.execute_prompt("Reply with only the word OK.", config)
    except LLMError as exc:
        elapsed = time.monotonic() - start
        click.echo(f"ERROR \u2014 LLM error after {elapsed:.1f}s: {exc}", err=True)
        # Targeted hint: 401 on openrouter almost always means a stale key.
        if (
            resolved.provider == "openrouter"
            and isinstance(exc, LLMAPIError)
            and exc.status_code == 401
        ):
            click.echo(
                "  hint: OpenRouter returned 401 (unauthorized). Check whether "
                "OPENROUTER_API_KEY is stale (`unset OPENROUTER_API_KEY` to "
                "fall back to the key in ~/.config/markitect/config.toml, or "
                "update the env var).",
                err=True,
            )
        sys.exit(1)
    except Exception as exc:
        elapsed = time.monotonic() - start
        click.echo(f"ERROR \u2014 Unexpected error after {elapsed:.1f}s: {exc}", err=True)
        sys.exit(1)

    elapsed = time.monotonic() - start
    resp_model = response.metadata.get("model", resolved.model)
    total_tokens = sum(response.usage.values()) if response.usage else "?"

    click.echo(
        f"OK \u2014 response in {elapsed:.1f}s, model: {resp_model}, "
        f"tokens: {total_tokens}"
    )


# ---------------------------------------------------------------------------
# llm-default / llm-preference — shared helpers
# ---------------------------------------------------------------------------

def _handle_set(section, section_label, user, provider, model):
    """Set a config section value."""
    if not provider and not model:
        click.echo(
            "Error: --set requires at least one of --provider/-p or --model/-m.",
            err=True,
        )
        sys.exit(1)

    if user:
        path = USER_CONFIG_PATH
        location = f"user {section_label}"
    else:
        path = _dir_config_path()
        if path is None:
            click.echo(
                "Error: No directory root found (no pyproject.toml). "
                "Use --user for user-level config.",
                err=True,
            )
            sys.exit(1)
        location = f"directory {section_label}"

    layer = LLMLayer(provider=provider, model=model)
    _write_llm_section(path, section, layer)

    parts = []
    if provider:
        parts.append(f"provider={provider}")
    if model:
        parts.append(f"model={model}")
    click.echo(f"Set {location}: {', '.join(parts)}")


def _handle_clear(section, section_label, user):
    """Clear a config section."""
    if user:
        path = USER_CONFIG_PATH
        location = f"user {section_label}"
    else:
        path = _dir_config_path()
        if path is None:
            click.echo(
                "Error: No directory root found (no pyproject.toml). "
                "Use --user for user-level config.",
                err=True,
            )
            sys.exit(1)
        location = f"directory {section_label}"

    if _clear_llm_section(path, section):
        click.echo(f"Cleared {location}.")
    else:
        click.echo(f"Nothing to clear ({location} was not set).")


def _show_layers(layers):
    """Render a list of (name, LLMLayer) as a table."""
    rows = []
    for name, layer in layers:
        rows.append({
            "layer": name,
            "provider": layer.provider or "\u2014",
            "model": layer.model or "\u2014",
        })
    headers = {"layer": "Layer", "provider": "Provider", "model": "Model"}
    click.echo(tabulate(rows, headers=headers, tablefmt="simple"))


# ---------------------------------------------------------------------------
# llm-default command
# ---------------------------------------------------------------------------

@click.command("llm-default")
@click.option(
    "--set", "action",
    flag_value="set",
    help="Set default provider/model.",
)
@click.option(
    "--clear", "action",
    flag_value="clear",
    help="Clear default config.",
)
@click.option(
    "--user",
    is_flag=True,
    default=False,
    help="Target user config instead of directory config.",
)
@click.option(
    "--provider", "-p",
    default=None,
    type=click.Choice(["openrouter", "claude-code", "gemini", "openai"]),
    help="LLM provider.",
)
@click.option(
    "--model", "-m",
    default=None,
    help="Model name.",
)
def llm_default_command(action, user, provider, model):
    """View or set the default LLM provider/model.

    \b
    Without flags, shows the default layers (directory and user defaults,
    plus the hardcoded fallback).

    \b
    Examples:
        markitect llm-default
        markitect llm-default --set -p openrouter -m qwen/qwen3-coder-next
        markitect llm-default --set --user -m anthropic/claude-sonnet-4
        markitect llm-default --clear
    """
    if action == "set":
        _handle_set("default", "default", user, provider, model)
    elif action == "clear":
        _handle_clear("default", "default", user)
    else:
        _show_layers(get_default_layers())


# ---------------------------------------------------------------------------
# llm-preference command
# ---------------------------------------------------------------------------

@click.command("llm-preference")
@click.option(
    "--set", "action",
    flag_value="set",
    help="Set preference provider/model.",
)
@click.option(
    "--clear", "action",
    flag_value="clear",
    help="Clear preference config.",
)
@click.option(
    "--user",
    is_flag=True,
    default=False,
    help="Target user config instead of directory config.",
)
@click.option(
    "--provider", "-p",
    default=None,
    type=click.Choice(["openrouter", "claude-code", "gemini", "openai"]),
    help="LLM provider.",
)
@click.option(
    "--model", "-m",
    default=None,
    help="Model name.",
)
def llm_preference_command(action, user, provider, model):
    """View or set the preferred LLM provider/model.

    \b
    Preferences override defaults. Without flags, shows the preference
    layers (user and directory preferences).

    \b
    Examples:
        markitect llm-preference
        markitect llm-preference --set -p openrouter -m anthropic/claude-sonnet-4
        markitect llm-preference --set --user -m anthropic/claude-sonnet-4
        markitect llm-preference --clear --user
    """
    if action == "set":
        _handle_set("preference", "preference", user, provider, model)
    elif action == "clear":
        _handle_clear("preference", "preference", user)
    else:
        _show_layers(get_preference_layers())