"""
Tool settings router.

Routes:
  GET  /settings/tools  → tool risk policy page
  POST /settings/tools  → save max_risk + per-tool overrides
"""

import html as _html
import json
import logging
from pathlib import Path

import jwt
from fastapi import APIRouter, Form, Request
from fastapi.responses import HTMLResponse, RedirectResponse

from auth_utils import COOKIE_NAME, decode_token, get_tool_policy, save_tool_policy
from persona import list_user_personas
from tools import TOOL_CATEGORIES, TOOL_RISK

logger = logging.getLogger(__name__)
router = APIRouter()

_STATIC = Path(__file__).parent.parent / "static"
_LAST_PERSONA_COOKIE = "cx_last_persona"


def _get_session_user(request: Request) -> str | None:
    token = request.cookies.get(COOKIE_NAME)
    if not token:
        return None
    try:
        return decode_token(token)
    except jwt.InvalidTokenError:
        return None


def _preferred_persona(request: Request, username: str) -> str:
    names = list_user_personas(username)
    if not names:
        return ""
    cookie_val = request.cookies.get(_LAST_PERSONA_COOKIE, "")
    return cookie_val if cookie_val in names else (names[0] if names else "")


def _build_tool_table(policy: dict) -> str:
    """Generate the per-tool override table rows grouped by category."""
    whitelist = set(policy.get("whitelist") or [])
    blacklist = set(policy.get("blacklist") or [])

    rows: list[str] = []
    for category, tools in TOOL_CATEGORIES.items():
        # Category header spanning all columns
        escaped_cat = _html.escape(category)
        rows.append(
            f'<tr><td colspan="4" style="padding:0.75rem 0.9rem 0.3rem;'
            f'font-size:0.72rem;font-weight:700;letter-spacing:0.07em;'
            f'text-transform:uppercase;color:var(--pg-dimmer);'
            f'border-bottom:1px solid var(--pg-border);">'
            f'{escaped_cat}</td></tr>'
        )
        for tool in tools:
            risk      = TOOL_RISK.get(tool, "medium")
            risk_cls  = f"risk-{risk}"
            risk_html = f'<span class="risk {risk_cls}">{_html.escape(risk)}</span>'

            # Override select value
            if tool in whitelist:
                override_val = "whitelist"
            elif tool in blacklist:
                override_val = "blacklist"
            else:
                override_val = "default"

            def _opt(val: str, label: str) -> str:
                sel = 'selected' if override_val == val else ''
                return f'<option value="{val}" {sel}>{label}</option>'

            override_sel = (
                f'<select name="override_{_html.escape(tool)}" '
                f'class="override-sel" data-tool="{_html.escape(tool)}">'
                + _opt("default",   "Default (auto)")
                + _opt("whitelist", "Force include")
                + _opt("blacklist", "Force exclude")
                + '</select>'
            )

            rows.append(
                f'<tr data-tool-risk="{_html.escape(risk)}">'
                f'<td class="tool-name">{_html.escape(tool)}</td>'
                f'<td>{risk_html}</td>'
                f'<td><span class="auto-pill"></span></td>'
                f'<td>{override_sel}</td>'
                f'</tr>'
            )

    table_body = "\n".join(rows)
    return (
        '<table class="tool-table">'
        '<thead><tr>'
        '<th>Tool</th><th>Risk</th><th>Auto status</th><th>Override</th>'
        '</tr></thead>'
        f'<tbody>{table_body}</tbody>'
        '</table>'
    )


def _tools_page(
    username: str,
    back_persona: str = "",
    success: str = "",
    error: str = "",
) -> str:
    html = (_STATIC / "tools_settings.html").read_text()
    policy  = get_tool_policy(username)
    max_risk = policy.get("max_risk") or ""

    # Max risk select options
    html = html.replace("{{ sel_none }}",   "selected" if max_risk == ""       else "")
    html = html.replace("{{ sel_low }}",    "selected" if max_risk == "low"    else "")
    html = html.replace("{{ sel_medium }}", "selected" if max_risk == "medium" else "")
    html = html.replace("{{ sel_high }}",   "selected" if max_risk == "high"   else "")

    html = html.replace("{{ tool_table_html }}", _build_tool_table(policy))
    html = html.replace("{{ tool_risk_json }}", json.dumps(TOOL_RISK))
    html = html.replace("{{ back_href }}", f"/{username}/{back_persona}" if back_persona else "/")
    html = html.replace("{{ help_href }}", f"/help?persona={back_persona}" if back_persona else "/help")

    if success:
        html = html.replace("<!-- SUCCESS -->", f'<p class="success">{success}</p>')
    if error:
        html = html.replace("<!-- ERROR -->", f'<p class="error">{error}</p>')
    return html


@router.get("/settings/tools", include_in_schema=False)
async def tools_page(request: Request):
    username = _get_session_user(request)
    if not username:
        return RedirectResponse("/login", status_code=302)
    back_persona = _preferred_persona(request, username)
    return HTMLResponse(_tools_page(username, back_persona))


@router.post("/settings/tools", include_in_schema=False)
async def save_tools(request: Request):
    username = _get_session_user(request)
    if not username:
        return RedirectResponse("/login", status_code=302)

    back_persona = _preferred_persona(request, username)
    form = await request.form()

    max_risk = (form.get("max_risk") or "").strip()
    if max_risk not in ("", "low", "medium", "high"):
        max_risk = ""

    whitelist: list[str] = []
    blacklist: list[str] = []

    all_tools = [t for tools in TOOL_CATEGORIES.values() for t in tools]
    for tool in all_tools:
        val = (form.get(f"override_{tool}") or "").strip()
        if val == "whitelist":
            whitelist.append(tool)
        elif val == "blacklist":
            blacklist.append(tool)

    # Merge into existing policy (preserve allow/deny confirmation-gate fields)
    policy = get_tool_policy(username)
    if max_risk:
        policy["max_risk"] = max_risk
    else:
        policy.pop("max_risk", None)

    policy["whitelist"] = whitelist
    policy["blacklist"] = blacklist

    save_tool_policy(username, policy)
    logger.info(
        "tool policy saved for %s: max_risk=%s whitelist=%d blacklist=%d",
        username, max_risk or "none", len(whitelist), len(blacklist),
    )
    return HTMLResponse(_tools_page(
        username, back_persona,
        success=f"Tool policy saved — max risk: {max_risk or 'none'}, "
                f"{len(whitelist)} whitelisted, {len(blacklist)} blacklisted.",
    ))