from __future__ import annotations

import os
import subprocess
from dataclasses import dataclass
from pathlib import Path
from typing import Any

from mcp.server.fastmcp import FastMCP
import psycopg
from psycopg.rows import dict_row


REPO_ROOT = Path(__file__).resolve().parents[1]
SCRIPTS_ROOT = REPO_ROOT / "scripts" / "auto-organized"
VPS_ROOT = REPO_ROOT / "vps"
CONTAINERS_ROOT = REPO_ROOT / "containers"
DATABASES_ROOT = REPO_ROOT / "databases"
K3S_ROOT = REPO_ROOT / "k3s"
POSTGRES_DSN_ENV = "INFRA_MCP_POSTGRES_DSN"
DOC_ALLOWLIST = (
    REPO_ROOT / "README.md",
    VPS_ROOT,
    CONTAINERS_ROOT,
    DATABASES_ROOT,
    K3S_ROOT,
)

READ_ONLY_SCRIPT_PREFIXES = (
    "check_",
    "fetch_",
    "get_",
    "inspect_",
    "verify_",
    "final_status",
    "watch_",
)
MUTATING_SCRIPT_PREFIXES = (
    "approve_",
    "complete_",
    "fix_",
    "merge_",
    "retrigger_",
    "revert_",
)

mcp = FastMCP(
    "infracloud-sustentacao",
    instructions=(
        "Use the real infracloud repository as the source of truth. "
        "Prefer inventory markdown, container unit files, and existing scripts. "
        "Do not assume paths like dev-scripts or docs/openproject if they do not exist. "
        "If Postgres is configured, prefer the MCP Postgres helpers for server-side persistence and diagnostics."
    ),
)


@dataclass(frozen=True)
class ScriptInfo:
    path: Path
    relative_path: str
    is_read_only: bool
    kind: str


def _postgres_dsn() -> str | None:
    value = os.getenv(POSTGRES_DSN_ENV, "").strip()
    return value or None


def _postgres_enabled() -> bool:
    return _postgres_dsn() is not None


def _get_pg_connection():
    dsn = _postgres_dsn()
    if not dsn:
        raise ValueError(f"{POSTGRES_DSN_ENV} is not configured")
    return psycopg.connect(dsn, row_factory=dict_row)


def _ensure_mcp_tables() -> None:
    if not _postgres_enabled():
        return

    with _get_pg_connection() as conn:
        with conn.cursor() as cur:
            cur.execute(
                """
                CREATE TABLE IF NOT EXISTS infra_mcp_notes (
                    id BIGSERIAL PRIMARY KEY,
                    scope TEXT NOT NULL,
                    title TEXT NOT NULL,
                    body TEXT NOT NULL,
                    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
                )
                """
            )
        conn.commit()


def _ensure_in_repo(path: Path) -> Path:
    resolved = path.resolve()
    if REPO_ROOT not in resolved.parents and resolved != REPO_ROOT:
        raise ValueError(f"path escapes repository root: {path}")
    return resolved


def _script_kind(name: str) -> str:
    lower = name.lower()
    if lower.endswith(".ps1"):
        return "powershell"
    if lower.endswith(".sh"):
        return "shell"
    return "other"


def _is_read_only_script(name: str) -> bool:
    lower = name.lower()
    if lower.endswith((".json", ".yaml", ".yml", ".txt", ".pem")):
        return False
    if lower.startswith(MUTATING_SCRIPT_PREFIXES):
        return False
    return lower.startswith(READ_ONLY_SCRIPT_PREFIXES)


def _list_scripts() -> list[ScriptInfo]:
    if not SCRIPTS_ROOT.exists():
        return []

    results: list[ScriptInfo] = []
    for path in sorted(SCRIPTS_ROOT.rglob("*")):
        if not path.is_file():
            continue
        relative = path.relative_to(REPO_ROOT).as_posix()
        results.append(
            ScriptInfo(
                path=path,
                relative_path=relative,
                is_read_only=_is_read_only_script(path.name),
                kind=_script_kind(path.name),
            )
        )
    return results


def _resolve_script(script_name: str) -> ScriptInfo:
    script_name = script_name.replace("\\", "/").strip()
    candidates = _list_scripts()

    exact = [item for item in candidates if item.relative_path == script_name or item.path.name == script_name]
    if len(exact) == 1:
        return exact[0]
    if len(exact) > 1:
        raise ValueError(f"multiple scripts matched '{script_name}', use a repo-relative path")

    fuzzy = [item for item in candidates if script_name.lower() in item.relative_path.lower()]
    if len(fuzzy) == 1:
        return fuzzy[0]
    if len(fuzzy) > 1:
        names = ", ".join(item.relative_path for item in fuzzy[:10])
        raise ValueError(f"multiple scripts matched '{script_name}': {names}")

    raise ValueError(f"script not found: {script_name}")


def _read_text(path: Path, max_chars: int = 20000) -> str:
    resolved = _ensure_in_repo(path)
    text = resolved.read_text(encoding="utf-8", errors="replace")
    if len(text) > max_chars:
        return text[:max_chars] + "\n... [truncated]"
    return text


def _parse_markdown_table(lines: list[str], start_index: int) -> tuple[list[dict[str, str]], int]:
    header_line = lines[start_index].strip()
    separator_index = start_index + 1
    if separator_index >= len(lines):
        return [], start_index + 1

    separator_line = lines[separator_index].strip()
    if "|" not in header_line or "|" not in separator_line:
        return [], start_index + 1

    headers = [part.strip(" `") for part in header_line.strip("|").split("|")]
    rows: list[dict[str, str]] = []
    index = start_index + 2
    while index < len(lines):
        line = lines[index].rstrip()
        if "|" not in line or not line.strip().startswith("|"):
            break
        values = [part.strip() for part in line.strip().strip("|").split("|")]
        if len(values) == len(headers):
            rows.append(dict(zip(headers, values)))
        index += 1

    return rows, index


def _parse_inventory_file(path: Path) -> dict[str, Any]:
    lines = _read_text(path, max_chars=120000).splitlines()
    parsed: dict[str, Any] = {"file": path.relative_to(REPO_ROOT).as_posix(), "sections": {}}
    current_section = "root"
    parsed["sections"][current_section] = {"tables": [], "paragraphs": []}

    index = 0
    while index < len(lines):
        line = lines[index].rstrip()
        if line.startswith("#"):
            current_section = line.lstrip("#").strip()
            parsed["sections"].setdefault(current_section, {"tables": [], "paragraphs": []})
            index += 1
            continue

        if line.strip().startswith("|"):
            rows, next_index = _parse_markdown_table(lines, index)
            if rows:
                parsed["sections"][current_section]["tables"].append(rows)
                index = next_index
                continue

        if line.strip():
            parsed["sections"][current_section]["paragraphs"].append(line.strip())
        index += 1

    return parsed


def _iter_inventory_files() -> list[Path]:
    return sorted(VPS_ROOT.rglob("services_inventory.md")) + sorted(K3S_ROOT.rglob("services_inventory.md"))


def _match_service(query: str, row: dict[str, str]) -> bool:
    haystack = " ".join(str(value) for value in row.values()).lower()
    return query.lower() in haystack


def _safe_doc_path(relative_path: str) -> Path:
    relative = Path(relative_path)
    candidate = _ensure_in_repo(REPO_ROOT / relative)
    for allowed in DOC_ALLOWLIST:
        allowed_resolved = allowed.resolve()
        if candidate == allowed_resolved or allowed_resolved in candidate.parents:
            return candidate
    raise ValueError(f"path not allowed: {relative_path}")


def _ensure_read_only_sql(sql: str) -> str:
    normalized = sql.strip().lstrip("(").strip().lower()
    if not normalized.startswith("select"):
        raise ValueError("only SELECT queries are allowed")
    forbidden = ("insert ", "update ", "delete ", "drop ", "alter ", "truncate ", "create ", "grant ", "revoke ")
    if any(token in normalized for token in forbidden):
        raise ValueError("query contains non-read-only statements")
    return sql


@mcp.tool(
    description="List scripts available in scripts/auto-organized, including whether each one is safe for read-only execution.",
)
def list_repo_scripts(name_filter: str | None = None) -> list[dict[str, Any]]:
    scripts = _list_scripts()
    if name_filter:
        scripts = [item for item in scripts if name_filter.lower() in item.relative_path.lower()]

    return [
        {
            "name": item.path.name,
            "relative_path": item.relative_path,
            "kind": item.kind,
            "read_only": item.is_read_only,
        }
        for item in scripts
    ]


@mcp.tool(
    description="Run an existing repo script from scripts/auto-organized. Only read-only diagnostic scripts are executable.",
)
def run_repo_script(script_name: str, args: list[str] | None = None, timeout_seconds: int = 60) -> dict[str, Any]:
    script = _resolve_script(script_name)
    if not script.is_read_only:
        raise ValueError(
            f"script '{script.relative_path}' is not classified as read-only and cannot be executed by this tool"
        )

    args = args or []
    if script.kind == "powershell":
        command = [
            "powershell",
            "-NoProfile",
            "-ExecutionPolicy",
            "Bypass",
            "-File",
            str(script.path),
            *args,
        ]
    elif script.kind == "shell":
        command = ["bash", str(script.path), *args]
    else:
        raise ValueError(f"unsupported script type: {script.kind}")

    completed = subprocess.run(
        command,
        cwd=REPO_ROOT,
        capture_output=True,
        text=True,
        timeout=timeout_seconds,
        check=False,
    )
    return {
        "script": script.relative_path,
        "exit_code": completed.returncode,
        "stdout": completed.stdout[-12000:],
        "stderr": completed.stderr[-12000:],
    }


@mcp.tool(
    description="Parse one services_inventory.md file into structured JSON. Server examples: redbull, vim, nc1, k3s.",
)
def read_services_inventory(server: str) -> dict[str, Any]:
    inventory_files = {path.parent.name.lower(): path for path in _iter_inventory_files()}
    server_key = server.lower().strip()
    if server_key not in inventory_files:
        raise ValueError(f"inventory not found for '{server}'. Available: {', '.join(sorted(inventory_files))}")
    return _parse_inventory_file(inventory_files[server_key])


@mcp.tool(
    description="Search all inventory files for an app, UUID, domain, server, or other service text.",
)
def find_service(query: str) -> list[dict[str, Any]]:
    matches: list[dict[str, Any]] = []
    for inventory_path in _iter_inventory_files():
        parsed = _parse_inventory_file(inventory_path)
        for section_name, section in parsed["sections"].items():
            for table in section["tables"]:
                for row in table:
                    if _match_service(query, row):
                        matches.append(
                            {
                                "inventory": parsed["file"],
                                "section": section_name,
                                "row": row,
                            }
                        )
    return matches


@mcp.tool(
    description="List Podman/Systemd unit files under containers/ and optionally filter by app name.",
)
def list_container_units(name_filter: str | None = None) -> list[dict[str, str]]:
    results: list[dict[str, str]] = []
    for path in sorted(CONTAINERS_ROOT.iterdir()):
        if not path.is_file():
            continue
        if path.suffix not in {".container", ".service"}:
            continue
        relative = path.relative_to(REPO_ROOT).as_posix()
        if name_filter and name_filter.lower() not in relative.lower():
            continue
        results.append({"name": path.name, "relative_path": relative, "kind": path.suffix.lstrip(".")})
    return results


@mcp.tool(
    description="Read a container unit file from containers/ for Podman/Systemd runtime analysis.",
)
def read_container_unit(name: str) -> dict[str, str]:
    candidates = [
        path
        for path in CONTAINERS_ROOT.iterdir()
        if path.is_file() and path.suffix in {".container", ".service"} and (path.name == name or name.lower() in path.name.lower())
    ]
    if not candidates:
        raise ValueError(f"container unit not found: {name}")
    if len(candidates) > 1:
        names = ", ".join(path.name for path in candidates)
        raise ValueError(f"multiple container units matched '{name}': {names}")

    path = candidates[0]
    return {
        "relative_path": path.relative_to(REPO_ROOT).as_posix(),
        "content": _read_text(path, max_chars=16000),
    }


@mcp.tool(
    description="Read a repo document from README, vps, databases, k3s, or containers paths.",
)
def read_repo_document(relative_path: str, max_chars: int = 12000) -> dict[str, str]:
    path = _safe_doc_path(relative_path)
    return {
        "relative_path": path.relative_to(REPO_ROOT).as_posix(),
        "content": _read_text(path, max_chars=max_chars),
    }


@mcp.tool(
    description="Search the repo for infrastructure terms such as app names, domains, env keys, or container names.",
)
def grep_repo(query: str, glob: str | None = None) -> dict[str, Any]:
    command = ["rg", "-n", query, str(REPO_ROOT)]
    if glob:
        command.extend(["-g", glob])

    completed = subprocess.run(
        command,
        cwd=REPO_ROOT,
        capture_output=True,
        text=True,
        timeout=30,
        check=False,
    )
    results = completed.stdout.splitlines()
    return {
        "exit_code": completed.returncode,
        "matches": results[:200],
        "truncated": len(results) > 200,
        "stderr": completed.stderr[-4000:],
    }


@mcp.tool(
    description="Return a compact summary of the actual infracloud repo layout so agents do not assume missing folders like dev-scripts or docs/openproject.",
)
def repo_layout_summary() -> dict[str, Any]:
    return {
        "repo_root": str(REPO_ROOT),
        "present_top_level_dirs": sorted(path.name for path in REPO_ROOT.iterdir() if path.is_dir()),
        "scripts_root": SCRIPTS_ROOT.relative_to(REPO_ROOT).as_posix() if SCRIPTS_ROOT.exists() else None,
        "inventory_files": [path.relative_to(REPO_ROOT).as_posix() for path in _iter_inventory_files()],
        "container_units": [path.name for path in CONTAINERS_ROOT.iterdir() if path.is_file() and path.suffix in {".container", ".service"}],
        "notes": [
            "The repo uses scripts/auto-organized instead of dev-scripts.",
            "The repo does not currently include docs/openproject.",
            "AGENT.md contains secrets and should not be used as a runtime configuration source.",
            f"Optional Postgres integration is enabled through {POSTGRES_DSN_ENV}.",
        ],
    }


@mcp.tool(
    description="Return the configured Postgres status for the MCP server and basic connectivity details.",
)
def postgres_healthcheck() -> dict[str, Any]:
    dsn = _postgres_dsn()
    if not dsn:
        return {"configured": False, "env_var": POSTGRES_DSN_ENV}

    with _get_pg_connection() as conn:
        with conn.cursor() as cur:
            cur.execute("SELECT current_database() AS database, current_user AS user, version() AS version")
            row = cur.fetchone()
    return {
        "configured": True,
        "env_var": POSTGRES_DSN_ENV,
        "database": row["database"],
        "user": row["user"],
        "version": row["version"],
    }


@mcp.tool(
    description="Execute a read-only SELECT query against the MCP Postgres database.",
)
def postgres_query(sql: str, limit: int = 100) -> dict[str, Any]:
    if limit < 1 or limit > 500:
        raise ValueError("limit must be between 1 and 500")

    safe_sql = _ensure_read_only_sql(sql)
    wrapped = f"SELECT * FROM ({safe_sql.rstrip().rstrip(';')}) AS q LIMIT {limit}"

    with _get_pg_connection() as conn:
        with conn.cursor() as cur:
            cur.execute(wrapped)
            rows = cur.fetchall()
    return {
        "row_count": len(rows),
        "rows": rows,
    }


@mcp.tool(
    description="Store a short operational note in the MCP Postgres database for future support sessions.",
)
def add_operational_note(scope: str, title: str, body: str) -> dict[str, Any]:
    if not scope.strip() or not title.strip() or not body.strip():
        raise ValueError("scope, title, and body are required")

    _ensure_mcp_tables()
    with _get_pg_connection() as conn:
        with conn.cursor() as cur:
            cur.execute(
                """
                INSERT INTO infra_mcp_notes (scope, title, body)
                VALUES (%s, %s, %s)
                RETURNING id, scope, title, body, created_at
                """,
                (scope.strip(), title.strip(), body.strip()),
            )
            row = cur.fetchone()
        conn.commit()
    return row


@mcp.tool(
    description="List recent operational notes stored in the MCP Postgres database.",
)
def list_operational_notes(scope: str | None = None, limit: int = 20) -> list[dict[str, Any]]:
    if limit < 1 or limit > 200:
        raise ValueError("limit must be between 1 and 200")

    _ensure_mcp_tables()
    query = """
        SELECT id, scope, title, body, created_at
        FROM infra_mcp_notes
    """
    params: list[Any] = []
    if scope and scope.strip():
        query += " WHERE scope = %s"
        params.append(scope.strip())
    query += " ORDER BY created_at DESC LIMIT %s"
    params.append(limit)

    with _get_pg_connection() as conn:
        with conn.cursor() as cur:
            cur.execute(query, params)
            return cur.fetchall()


if __name__ == "__main__":
    _ensure_mcp_tables()
    mcp.run()