"""Doctor command implementation for MindRoom CLI."""

from __future__ import annotations

import ipaddress
import os
import tempfile
from pathlib import Path
from typing import TYPE_CHECKING
from urllib.parse import urlparse

import httpx
import typer
import yaml
from agno.models.vertexai.claude import Claude as VertexAIClaude
from anthropic import APIStatusError
from google.auth.exceptions import DefaultCredentialsError, RefreshError
from pydantic import ValidationError

from mindroom.constants import (
    CONFIG_PATH,
    MATRIX_HOMESERVER,
    MATRIX_SSL_VERIFY,
    STORAGE_PATH,
    env_key_for_provider,
)
from mindroom.matrix.health import matrix_versions_url, response_has_matrix_versions

from .config import _load_config_quiet, console

if TYPE_CHECKING:
    from collections.abc import Callable

    from mindroom.config.main import Config
    from mindroom.config.models import ModelConfig


def doctor() -> None:
    """Check your environment for common issues.

    Runs connectivity, configuration, and credential checks in a single pass
    so you can fix everything before running `mindroom run`.
    """
    console.print("[bold]MindRoom Doctor[/bold]\n")

    passed = 0
    failed = 0
    warnings = 0

    config_path = Path(CONFIG_PATH)

    # 1. Config file exists
    p, f, w = _run_doctor_step("Checking config file...", lambda: _check_config_exists(config_path))
    passed += p
    failed += f
    warnings += w

    # 2+. Config validity + provider API key validation (skip if file missing)
    if config_path.exists():
        config, p, f, w = _run_doctor_step(
            "Validating configuration...",
            lambda: _check_config_valid(config_path),
        )
        passed += p
        failed += f
        warnings += w
        if config is not None:
            p, f, w = _run_doctor_step("Checking providers...", lambda: _check_providers(config))
            passed += p
            failed += f
            warnings += w

            # 4. Memory LLM & embedder
            p, f, w = _run_doctor_step(
                "Checking memory config...",
                lambda: _check_memory_config(config),
            )
            passed += p
            failed += f
            warnings += w

    # 5. Matrix homeserver reachable
    p, f, w = _run_doctor_step("Checking Matrix homeserver...", _check_matrix_homeserver)
    passed += p
    failed += f
    warnings += w

    # 6. Storage directory writable
    p, f, w = _run_doctor_step("Checking storage...", _check_storage_writable)
    passed += p
    failed += f
    warnings += w

    # Summary
    console.print(f"\n{passed} passed, {failed} failed, {warnings} warning{'s' if warnings != 1 else ''}")

    if failed > 0:
        raise typer.Exit(1)


def _run_doctor_step[T](message: str, check: Callable[[], T]) -> T:
    """Run one doctor step with a minimal terminal spinner."""
    with console.status(f"[dim]{message}[/dim]", spinner="dots"):
        return check()


def _check_config_exists(config_path: Path) -> tuple[int, int, int]:
    """Check config file exists. Returns (passed, failed, warnings)."""
    if config_path.exists():
        console.print(f"[green]✓[/green] Config file: {config_path}")
        return 1, 0, 0
    console.print(f"[red]✗[/red] Config file not found: {config_path}")
    return 0, 1, 0


def _check_config_valid(config_path: Path) -> tuple[Config | None, int, int, int]:
    """Validate config file. Returns (config_or_none, passed, failed, warnings)."""
    try:
        config = _load_config_quiet(config_path)
    except ValidationError as exc:
        n = len(exc.errors())
        console.print(f"[red]✗[/red] Config invalid ({n} validation error{'s' if n != 1 else ''})")
        return None, 0, 1, 0
    except (yaml.YAMLError, OSError) as exc:
        console.print(f"[red]✗[/red] Config invalid: {exc}")
        return None, 0, 1, 0
    agents = len(config.agents)
    teams = len(config.teams)
    models = len(config.models)
    rooms = len(config.get_all_configured_rooms())
    console.print(
        f"[green]✓[/green] Config valid"
        f" ({agents} agent{'s' if agents != 1 else ''},"
        f" {teams} team{'s' if teams != 1 else ''},"
        f" {models} model{'s' if models != 1 else ''},"
        f" {rooms} room{'s' if rooms != 1 else ''})",
    )
    return config, 1, 0, 0


_PROVIDER_VALIDATE_URLS: dict[str, str] = {
    "anthropic": "https://api.anthropic.com/v1/models",
    "openai": "https://api.openai.com/v1/models",
    "google": "https://generativelanguage.googleapis.com/v1beta/models",
    "openrouter": "https://openrouter.ai/api/v1/models",
    "deepseek": "https://api.deepseek.com/v1/models",
    "cerebras": "https://api.cerebras.ai/v1/models",
    "groq": "https://api.groq.com/openai/v1/models",
}


def _get_custom_base_url(config: Config, provider: str) -> str | None:
    """Get custom base_url for a provider from model extra_kwargs, if any."""
    for model in config.models.values():
        if model.provider == provider and model.extra_kwargs:
            base_url = model.extra_kwargs.get("base_url")
            if base_url:
                return base_url
    return None


def _http_check(
    url: str,
    headers: dict[str, str] | None = None,
    *,
    verify: bool = True,
) -> tuple[bool | None, str]:
    """Make a lightweight GET request and return (True, ""), (False, reason), or (None, reason)."""
    try:
        resp = httpx.get(url, headers=headers or {}, timeout=5, verify=verify)
    except httpx.HTTPError as exc:
        return None, str(exc)
    if resp.is_success:
        return True, ""
    return False, f"HTTP {resp.status_code}"


def _is_local_network_host(host: str) -> bool:
    """Return True for .local, loopback, and private-link hosts."""
    normalized_host = host.strip().strip("[]").lower()
    if normalized_host in {"localhost", "127.0.0.1", "::1"} or normalized_host.endswith(".local"):
        return True
    try:
        ip = ipaddress.ip_address(normalized_host)
    except ValueError:
        return False
    return ip.is_private or ip.is_loopback or ip.is_link_local


def _with_local_network_hint(detail: str, base_url: str | None) -> str:
    """Append a targeted hint for local host routing failures."""
    if not detail or not base_url:
        return detail

    parsed = urlparse(base_url)
    host = parsed.hostname
    if host is None or not _is_local_network_host(host):
        return detail

    lowered = detail.lower()
    route_signals = (
        "no route to host",
        "connection refused",
        "name or service not known",
        "nodename nor servname provided",
    )
    if not any(signal in lowered for signal in route_signals):
        return detail

    return (
        f"{detail}; local host '{host}' may be unreachable from this Python runtime"
        " (try a reachable LAN IP instead of .local)"
    )


def _validate_openai_embeddings_endpoint(
    api_key: str,
    base_url: str,
    model: str,
) -> tuple[bool | None, str]:
    """Validate a custom OpenAI-compatible embeddings endpoint with a tiny request."""
    url = f"{base_url.rstrip('/')}/embeddings"
    headers = {"Authorization": f"Bearer {api_key}"} if api_key else {}
    payload = {"model": model, "input": "mindroom doctor embedder check"}

    try:
        resp = httpx.post(url, headers=headers, json=payload, timeout=10)
    except httpx.HTTPError as exc:
        return None, str(exc)

    if not resp.is_success:
        return False, f"HTTP {resp.status_code}"

    error_detail: str | None = None
    try:
        body = resp.json()
    except ValueError:
        error_detail = "invalid JSON response"
    else:
        data = body.get("data") if isinstance(body, dict) else None
        if not isinstance(data, list) or not data:
            error_detail = "missing embeddings data"
        else:
            first_item = data[0]
            if not isinstance(first_item, dict):
                error_detail = "invalid embeddings payload"
            else:
                embedding = first_item.get("embedding")
                if not isinstance(embedding, list) or not embedding:
                    error_detail = "empty embedding vector"

    if error_detail is not None:
        return False, error_detail

    return True, ""


def _validate_provider_key(
    provider: str,
    api_key: str,
    base_url: str | None = None,
) -> tuple[bool | None, str]:
    """Validate an API key with a lightweight models-list request.

    Returns (True, "") if valid, (False, reason) if invalid,
    (None, reason) if inconclusive (e.g. connection error).
    """
    # Normalize aliases so we look up a single URL and auth style
    canonical = "google" if provider == "gemini" else provider

    if base_url:
        url = base_url.rstrip("/") + "/models"
    elif canonical in _PROVIDER_VALIDATE_URLS:
        url = _PROVIDER_VALIDATE_URLS[canonical]
    else:
        return None, "unknown provider"

    headers: dict[str, str] = {}
    if canonical == "anthropic":
        headers = {"x-api-key": api_key, "anthropic-version": "2023-06-01"}
    elif canonical == "google":
        url = f"{url}?key={api_key}"
    else:
        headers = {"Authorization": f"Bearer {api_key}"}

    return _http_check(url, headers)


def _validate_vertexai_claude_connection(model_config: ModelConfig) -> tuple[bool | None, str]:
    """Validate the configured Vertex AI Claude model with the runtime request path."""
    extra_kwargs = dict(model_config.extra_kwargs or {})
    project_id = extra_kwargs.get("project_id") or os.getenv("ANTHROPIC_VERTEX_PROJECT_ID")
    region = extra_kwargs.get("region") or os.getenv("CLOUD_ML_REGION")
    missing = []
    if not project_id:
        missing.append("ANTHROPIC_VERTEX_PROJECT_ID")
    if not region:
        missing.append("CLOUD_ML_REGION")
    if missing:
        return None, f"missing {', '.join(missing)}"

    extra_kwargs.setdefault("project_id", project_id)
    extra_kwargs.setdefault("region", region)
    extra_kwargs.setdefault("timeout", 10)

    try:
        model = VertexAIClaude(id=model_config.id, **extra_kwargs)
        request_kwargs = model.get_request_params().copy()
        request_kwargs["model"] = model_config.id
        request_kwargs["messages"] = [{"role": "user", "content": "Reply with OK."}]
        request_kwargs.setdefault("max_tokens", 1)
        request_kwargs["timeout"] = request_kwargs.get("timeout", 10)
        client = model.get_client()
        client.messages.create(
            **request_kwargs,
        )
    except APIStatusError as exc:
        return False, f"HTTP {exc.status_code}"
    except DefaultCredentialsError as exc:
        return None, str(exc)
    except RefreshError as exc:
        return False, str(exc)
    except (RuntimeError, TypeError, ValueError, httpx.HTTPError) as exc:
        return None, str(exc)

    return True, ""


def _get_ollama_host(config: Config) -> str:
    """Get the Ollama host from config or environment."""
    for model in config.models.values():
        if model.provider == "ollama" and model.host:
            return model.host
    return os.getenv("OLLAMA_HOST", "http://localhost:11434")


def _check_providers(config: Config) -> tuple[int, int, int]:
    """Print provider summary and validate API keys. Returns (passed, failed, warnings)."""
    provider_models: dict[str, list[str]] = {}
    for name, model in config.models.items():
        provider_models.setdefault(model.provider, []).append(name)

    if not provider_models:
        return 0, 0, 0

    # Print provider summary
    parts = []
    for provider in sorted(provider_models):
        n = len(provider_models[provider])
        parts.append(f"{provider} ({n} model{'s' if n != 1 else ''})")
    console.print(f"  Providers: {', '.join(parts)}")

    passed = 0
    failed = 0
    warnings = 0
    validated_keys: set[str] = set()

    for provider in sorted(provider_models):
        p, f, w = _check_single_provider(provider, config, validated_keys)
        passed += p
        failed += f
        warnings += w

    return passed, failed, warnings


def _print_validation(
    valid: bool | None,
    detail: str,
    pass_msg: str,
    fail_msg: str,
    warn_msg: str,
) -> tuple[int, int, int]:
    """Print a tri-state validation result. Returns (passed, failed, warnings)."""
    if valid is True:
        console.print(f"[green]✓[/green] {pass_msg}")
        return 1, 0, 0
    if valid is False:
        console.print(f"[red]✗[/red] {fail_msg} ({detail})")
        return 0, 1, 0
    console.print(f"[yellow]![/yellow] {warn_msg} ({detail})")
    return 0, 0, 1


def _check_single_provider(
    provider: str,
    config: Config,
    validated_keys: set[str],
) -> tuple[int, int, int]:
    """Validate a single provider. Returns (passed, failed, warnings)."""
    if provider == "vertexai_claude":
        passed = 0
        failed = 0
        warnings = 0
        for model_config in config.models.values():
            if model_config.provider != provider:
                continue
            valid, detail = _validate_vertexai_claude_connection(model_config)
            p, f, w = _print_validation(
                valid,
                detail,
                f"{provider} connection valid for {model_config.id}",
                f"{provider} connection failed for {model_config.id}",
                f"{provider}: could not validate connection for {model_config.id}",
            )
            passed += p
            failed += f
            warnings += w
        return passed, failed, warnings

    if provider == "ollama":
        host = _get_ollama_host(config)
        url = f"{host.rstrip('/')}/api/tags"
        valid, detail = _http_check(url)
        return _print_validation(
            valid,
            detail,
            f"{provider} reachable ({host})",
            f"{provider} unreachable: {host}",
            f"{provider}: could not reach {host}",
        )

    env_key = env_key_for_provider(provider)
    if not env_key:
        return 0, 0, 0

    # google and gemini share GOOGLE_API_KEY — validate once
    if env_key in validated_keys:
        return 0, 0, 0
    validated_keys.add(env_key)

    api_key = os.getenv(env_key)
    if not api_key:
        console.print(f"[yellow]![/yellow] {provider}: {env_key} not set")
        return 0, 0, 1

    base_url = _get_custom_base_url(config, provider)
    valid, detail = _validate_provider_key(provider, api_key, base_url)
    return _print_validation(
        valid,
        detail,
        f"{provider} API key valid",
        f"{provider} API key invalid",
        f"{provider}: could not validate key",
    )


def _check_memory_config(config: Config) -> tuple[int, int, int]:
    """Check memory LLM and embedder configuration. Returns (passed, failed, warnings)."""
    if not config.uses_mem0_memory():
        console.print("[green]✓[/green] Memory backend: file (markdown)")
        return 1, 0, 0

    if config.uses_file_memory():
        console.print("[green]✓[/green] Memory backend: mixed (per-agent mem0/file)")

    p1, f1, w1 = _check_memory_llm(config)
    p2, f2, w2 = _check_memory_embedder(config)
    return p1 + p2, f1 + f2, w1 + w2


def _check_memory_llm(config: Config) -> tuple[int, int, int]:
    """Check memory LLM configuration. Returns (passed, failed, warnings)."""
    if config.memory.llm is None:
        ollama_host = _get_ollama_host(config)
        console.print(
            "[yellow]![/yellow] Memory LLM not configured"
            f" (defaults to ollama at {ollama_host};"
            " see memory/config.py fallback)",
        )
        # Check if default Ollama is reachable
        valid, detail = _http_check(f"{ollama_host.rstrip('/')}/api/tags")
        if valid is not True:
            console.print(
                f"[red]✗[/red] Default Ollama for memory LLM unreachable ({ollama_host}: {detail})",
            )
            return 0, 1, 0
        return 0, 0, 1

    llm_provider = config.memory.llm.provider
    llm_host = config.memory.llm.config.get("host")
    if llm_provider == "ollama":
        host = llm_host or _get_ollama_host(config)
        valid, detail = _http_check(f"{host.rstrip('/')}/api/tags")
        return _print_validation(
            valid,
            detail,
            f"Memory LLM: ollama reachable ({host})",
            f"Memory LLM: ollama unreachable ({host})",
            f"Memory LLM: could not reach ollama ({host})",
        )

    llm_model = config.memory.llm.config.get("model", "default")
    env_key = env_key_for_provider(llm_provider)
    api_key = os.getenv(env_key) if env_key else None
    if env_key and not api_key:
        console.print(
            f"[yellow]![/yellow] Memory LLM ({llm_provider}): {env_key} not set",
        )
        return 0, 0, 1
    base_url = llm_host
    valid, detail = _validate_provider_key(llm_provider, api_key or "", base_url)
    return _print_validation(
        valid,
        detail,
        f"Memory LLM: {llm_provider}/{llm_model} API key valid",
        f"Memory LLM: {llm_provider}/{llm_model} API key invalid",
        f"Memory LLM: {llm_provider}/{llm_model} could not validate",
    )


def _check_memory_embedder(config: Config) -> tuple[int, int, int]:
    """Check memory embedder configuration. Returns (passed, failed, warnings)."""
    emb = config.memory.embedder
    if emb.provider == "ollama":
        host = emb.config.host or _get_ollama_host(config)
        valid, detail = _http_check(f"{host.rstrip('/')}/api/tags")
        return _print_validation(
            valid,
            detail,
            f"Memory embedder: ollama reachable ({host})",
            f"Memory embedder: ollama unreachable ({host})",
            f"Memory embedder: could not reach ollama ({host})",
        )

    env_key = env_key_for_provider(emb.provider)
    api_key = os.getenv(env_key) if env_key else None
    if env_key and not api_key:
        console.print(
            f"[yellow]![/yellow] Memory embedder ({emb.provider}): {env_key} not set",
        )
        return 0, 0, 1

    if emb.provider == "openai" and emb.config.host:
        valid, detail = _validate_openai_embeddings_endpoint(api_key or "", emb.config.host, emb.config.model)
        return _print_validation(
            valid,
            _with_local_network_hint(detail, emb.config.host),
            f"Memory embedder: openai/{emb.config.model} embeddings endpoint reachable ({emb.config.host})",
            f"Memory embedder: openai/{emb.config.model} embeddings endpoint failed ({emb.config.host})",
            f"Memory embedder: openai/{emb.config.model} could not reach embeddings endpoint ({emb.config.host})",
        )

    base_url = emb.config.host
    valid, detail = _validate_provider_key(emb.provider, api_key or "", base_url)
    return _print_validation(
        valid,
        detail,
        f"Memory embedder: {emb.provider}/{emb.config.model} API key valid",
        f"Memory embedder: {emb.provider}/{emb.config.model} API key invalid",
        f"Memory embedder: {emb.provider}/{emb.config.model} could not validate",
    )


def _check_matrix_homeserver() -> tuple[int, int, int]:
    """Check Matrix homeserver reachability. Returns (passed, failed, warnings)."""
    url = matrix_versions_url(MATRIX_HOMESERVER)
    try:
        response = httpx.get(url, timeout=5, verify=MATRIX_SSL_VERIFY)
    except httpx.TransportError as exc:
        console.print(f"[red]✗[/red] Matrix homeserver unreachable: {MATRIX_HOMESERVER} ({exc})")
        return 0, 1, 0
    if response_has_matrix_versions(response):
        console.print(f"[green]✓[/green] Matrix homeserver: {MATRIX_HOMESERVER}")
        return 1, 0, 0
    detail = f"HTTP {response.status_code}" if not response.is_success else "returned invalid /versions payload"
    console.print(f"[red]✗[/red] Matrix homeserver {detail}: {MATRIX_HOMESERVER}")
    return 0, 1, 0


def _check_storage_writable() -> tuple[int, int, int]:
    """Check storage directory is writable. Returns (passed, failed, warnings)."""
    storage = Path(STORAGE_PATH)
    try:
        storage.mkdir(parents=True, exist_ok=True)
        fd, tmp = tempfile.mkstemp(dir=storage)
        os.close(fd)
        Path(tmp).unlink()
    except OSError as exc:
        console.print(f"[red]✗[/red] Storage not writable: {storage} ({exc})")
        return 0, 1, 0
    console.print(f"[green]✓[/green] Storage writable: {storage}/")
    return 1, 0, 0
