"""Agent Dashboards — a tiny agent-updatable dashboard service.

Agents create/update dashboards and push data over a bearer-authed REST API. Each dashboard is
served at its own URL as rendered HTML (and JSON). Mutations update an in-memory store immediately;
the store is synced to durable backups (GitHub primary + HF Dataset fallback) once a day at a fixed
hour, on graceful shutdown, or on demand via POST /api/sync.
"""
import os
import io
import json
import html
import time
import base64
import threading
from datetime import datetime
from zoneinfo import ZoneInfo

import requests
from fastapi import FastAPI, Header, HTTPException, Request
from fastapi.responses import HTMLResponse

# ---- config -----------------------------------------------------------------
AGENT_KEY = os.environ.get("AGENT_KEY", "")
STORE_FILE = os.environ.get("STORE_FILE", "store.json")
# primary backup: GitHub repo (Contents API)
GITHUB_TOKEN = os.environ.get("GITHUB_TOKEN", "")
GITHUB_REPO = os.environ.get("GITHUB_REPO", "JsonLord/dashboard-backups")
GITHUB_BRANCH = os.environ.get("GITHUB_BRANCH", "main")
GH_API = f"https://api.github.com/repos/{GITHUB_REPO}/contents/{STORE_FILE}"
# fallback backup: HF Dataset repo
HF_TOKEN = os.environ.get("HF_TOKEN", "")
DATASET_REPO = os.environ.get("DATASET_REPO", "")
# scheduled sync: once a day at SYNC_HOUR in SYNC_TZ
SYNC_HOUR = int(os.environ.get("SYNC_HOUR", "20"))
try:
    SYNC_TZ = ZoneInfo(os.environ.get("SYNC_TZ", "UTC"))
except Exception:
    SYNC_TZ = ZoneInfo("UTC")

app = FastAPI(title="Agent Dashboards", docs_url="/docs")

_lock = threading.Lock()
_store = {"dashboards": {}}   # id -> dashboard dict
_sha = None                   # GitHub blob sha for in-place updates
_dirty = False                # unsynced in-memory changes?
_last_sync = None             # iso timestamp of last successful remote sync


def _payload():
    return json.dumps(_store, ensure_ascii=False, indent=2).encode("utf-8")


def _valid(data):
    return isinstance(data, dict) and isinstance(data.get("dashboards"), dict)


# ---- backup target: GitHub --------------------------------------------------
def _gh_headers():
    return {"Authorization": f"Bearer {GITHUB_TOKEN}",
            "Accept": "application/vnd.github+json",
            "X-GitHub-Api-Version": "2022-11-28"}


def _gh_load():
    global _sha
    if not GITHUB_TOKEN:
        return None
    r = requests.get(GH_API, headers=_gh_headers(), params={"ref": GITHUB_BRANCH}, timeout=15)
    if r.status_code == 404:
        return None
    r.raise_for_status()
    j = r.json()
    _sha = j.get("sha")
    return json.loads(base64.b64decode(j["content"]))


def _gh_save(payload):
    global _sha
    body = {"message": "sync dashboards", "branch": GITHUB_BRANCH,
            "content": base64.b64encode(payload).decode("ascii")}
    if _sha:
        body["sha"] = _sha
    r = requests.put(GH_API, headers=_gh_headers(), json=body, timeout=20)
    if r.status_code in (409, 422) and _sha:  # stale sha -> refetch + retry once
        g = requests.get(GH_API, headers=_gh_headers(), params={"ref": GITHUB_BRANCH}, timeout=15)
        if g.ok:
            _sha = g.json().get("sha")
            body["sha"] = _sha
            r = requests.put(GH_API, headers=_gh_headers(), json=body, timeout=20)
    r.raise_for_status()
    _sha = r.json().get("content", {}).get("sha", _sha)


# ---- backup target: HF Dataset (fallback) -----------------------------------
def _hf_load():
    if not (HF_TOKEN and DATASET_REPO):
        return None
    from huggingface_hub import HfApi
    path = HfApi(token=HF_TOKEN).hf_hub_download(
        repo_id=DATASET_REPO, repo_type="dataset", filename=STORE_FILE, force_download=True)
    with open(path, encoding="utf-8") as fh:
        return json.load(fh)


def _hf_save(payload):
    if not (HF_TOKEN and DATASET_REPO):
        return
    from huggingface_hub import HfApi
    HfApi(token=HF_TOKEN).upload_file(
        path_or_fileobj=io.BytesIO(payload), path_in_repo=STORE_FILE,
        repo_id=DATASET_REPO, repo_type="dataset", commit_message="sync dashboards")


# ---- load / sync ------------------------------------------------------------
def _load():
    global _store
    for name, fn in (("github", _gh_load), ("hf-dataset", _hf_load)):
        try:
            data = fn()
            if _valid(data):
                _store = data
                print(f"[store] loaded {len(_store['dashboards'])} dashboard(s) from {name}")
                return
        except Exception as exc:
            print(f"[store] load from {name} failed: {exc}")
    print("[store] starting empty")


def _sync(reason="scheduled"):
    """Push the in-memory store to GitHub (primary) + HF Dataset (fallback)."""
    global _dirty, _last_sync
    payload = _payload()
    ok = []
    for name, fn in (("github", _gh_save), ("hf-dataset", _hf_save)):
        try:
            fn(payload)
            ok.append(name)
        except Exception as exc:
            print(f"[sync] {name} failed: {exc}")
    if ok:
        _dirty = False
        _last_sync = datetime.now(SYNC_TZ).isoformat(timespec="seconds")
        print(f"[sync] {reason}: pushed to {', '.join(ok)}")
    return ok


def _touch():
    global _dirty
    _dirty = True


def _scheduler():
    last_run = None
    while True:
        try:
            now = datetime.now(SYNC_TZ)
            if now.hour == SYNC_HOUR and last_run != now.date():
                with _lock:
                    if _dirty:
                        _sync(f"daily {SYNC_HOUR:02d}:00")
                last_run = now.date()
        except Exception as exc:
            print(f"[scheduler] {exc}")
        time.sleep(30)


@app.on_event("startup")
def _startup():
    _load()
    threading.Thread(target=_scheduler, daemon=True).start()
    print(f"[store] daily sync armed for {SYNC_HOUR:02d}:00 {SYNC_TZ.key}")


@app.on_event("shutdown")
def _shutdown():
    with _lock:
        if _dirty:
            _sync("shutdown flush")


# ---- auth -------------------------------------------------------------------
def _require_key(authorization: str | None):
    if not AGENT_KEY:
        raise HTTPException(500, "AGENT_KEY not configured on the server")
    token = ""
    if authorization and authorization.lower().startswith("bearer "):
        token = authorization[7:].strip()
    if token != AGENT_KEY:
        raise HTTPException(401, "missing or invalid bearer token")


def _now():
    return datetime.now(SYNC_TZ).isoformat(timespec="seconds")


def _norm(dash_id: str, body: dict, existing: dict | None = None) -> dict:
    now = _now()
    base = existing or {"created_at": now}
    return {
        "id": dash_id,
        "title": str(body.get("title") or (existing or {}).get("title") or dash_id),
        "widgets": body.get("widgets", (existing or {}).get("widgets", [])) or [],
        "data": body.get("data", (existing or {}).get("data", {})) or {},
        "created_at": base.get("created_at", now),
        "updated_at": now,
    }


# ---- JSON API ---------------------------------------------------------------
@app.get("/health")
def health():
    return {"status": "ok", "dashboards": len(_store["dashboards"]),
            "dirty": _dirty, "last_sync": _last_sync,
            "next_sync": f"{SYNC_HOUR:02d}:00 {SYNC_TZ.key}"}


@app.post("/api/sync")
def manual_sync(authorization: str | None = Header(default=None)):
    _require_key(authorization)
    with _lock:
        ok = _sync("manual")
    return {"synced_to": ok, "dirty": _dirty, "last_sync": _last_sync}


@app.get("/api/dashboards")
def list_dashboards(authorization: str | None = Header(default=None)):
    _require_key(authorization)
    return {"dashboards": [
        {"id": d["id"], "title": d["title"], "widgets": len(d.get("widgets", [])),
         "updated_at": d.get("updated_at")}
        for d in _store["dashboards"].values()
    ]}


@app.get("/api/dashboards/{dash_id}")
def get_dashboard(dash_id: str, authorization: str | None = Header(default=None)):
    _require_key(authorization)
    d = _store["dashboards"].get(dash_id)
    if not d:
        raise HTTPException(404, "dashboard not found")
    return d


@app.post("/api/dashboards")
async def create_dashboard(request: Request, authorization: str | None = Header(default=None)):
    _require_key(authorization)
    body = await request.json()
    if not isinstance(body, dict) or not body.get("id"):
        raise HTTPException(400, "body must include an 'id'")
    dash_id = str(body["id"])
    with _lock:
        _store["dashboards"][dash_id] = _norm(dash_id, body, _store["dashboards"].get(dash_id))
        _touch()
        return _store["dashboards"][dash_id]


@app.put("/api/dashboards/{dash_id}")
async def update_dashboard(dash_id: str, request: Request,
                           authorization: str | None = Header(default=None)):
    _require_key(authorization)
    body = await request.json()
    with _lock:
        existing = _store["dashboards"].get(dash_id)
        if not existing:
            raise HTTPException(404, "dashboard not found")
        merged = dict(existing)
        if "title" in body:
            merged["title"] = str(body["title"])
        if "widgets" in body:
            merged["widgets"] = body["widgets"] or []
        if "data" in body:
            merged["data"] = body["data"] or {}
        merged["updated_at"] = _now()
        _store["dashboards"][dash_id] = merged
        _touch()
        return merged


@app.put("/api/dashboards/{dash_id}/data")
async def update_data(dash_id: str, request: Request,
                      authorization: str | None = Header(default=None)):
    _require_key(authorization)
    body = await request.json()
    if not isinstance(body, dict):
        raise HTTPException(400, "data body must be a JSON object of {key: value}")
    with _lock:
        d = _store["dashboards"].get(dash_id)
        if not d:
            raise HTTPException(404, "dashboard not found")
        data = dict(d.get("data", {}))
        data.update(body)  # shallow merge
        d["data"] = data
        d["updated_at"] = _now()
        _touch()
        return d


@app.delete("/api/dashboards/{dash_id}")
def delete_dashboard(dash_id: str, authorization: str | None = Header(default=None)):
    _require_key(authorization)
    with _lock:
        if dash_id not in _store["dashboards"]:
            raise HTTPException(404, "dashboard not found")
        del _store["dashboards"][dash_id]
        _touch()
    return {"deleted": dash_id}


# ---- HTML rendering ---------------------------------------------------------
CSS = """
:root{--bg:#f6f7f9;--card:#fff;--ink:#111827;--muted:#6b7280;--line:#e5e7eb;--accent:#4f46e5}
@media (prefers-color-scheme:dark){:root{--bg:#0b0f17;--card:#141a24;--ink:#e5e7eb;--muted:#9aa4b2;--line:#232b36;--accent:#8b8cf9}}
*{box-sizing:border-box}body{margin:0;background:var(--bg);color:var(--ink);
font:15px/1.5 -apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,sans-serif}
.wrap{max-width:1100px;margin:0 auto;padding:28px 20px 60px}
a{color:var(--accent);text-decoration:none}a:hover{text-decoration:underline}
h1{font-size:24px;margin:0 0 4px}.sub{color:var(--muted);margin:0 0 24px;font-size:13px}
.grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(260px,1fr));gap:16px}
.card{background:var(--card);border:1px solid var(--line);border-radius:14px;padding:16px 18px}
.card h3{margin:0 0 10px;font-size:13px;letter-spacing:.02em;text-transform:uppercase;color:var(--muted)}
.metric .val{font-size:34px;font-weight:700;line-height:1.1}
.metric .unit{font-size:18px;color:var(--muted);font-weight:600}
.delta{font-size:13px;margin-top:6px}.delta.up{color:#16a34a}.delta.down{color:#dc2626}
table{width:100%;border-collapse:collapse;font-size:14px}
th,td{text-align:left;padding:7px 8px;border-bottom:1px solid var(--line)}
th{color:var(--muted);font-weight:600;font-size:12px;text-transform:uppercase}
.full{grid-column:1/-1}.idx a{display:block}.idx .card{transition:border-color .15s}
.idx .card:hover{border-color:var(--accent)}
.empty{color:var(--muted);padding:40px;text-align:center;border:1px dashed var(--line);border-radius:14px}
canvas{max-width:100%}.foot{margin-top:28px;color:var(--muted);font-size:12px}
"""


def _esc(x):
    return html.escape("" if x is None else str(x))


def _effective(widget, data):
    eff = dict(widget)
    key = widget.get("dataKey")
    if key and isinstance(data.get(key), dict):
        eff.update(data[key])
    return eff


def _render_widget(widget, data, idx):
    w = _effective(widget, data)
    wtype = (w.get("type") or "metric").lower()
    title = _esc(w.get("title", ""))
    cls = "card full" if wtype in ("chart", "table") else "card"
    head = f"<h3>{title}</h3>" if title else ""

    if wtype == "metric":
        val = w.get("value", "—")
        unit = w.get("unit", "")
        delta = w.get("delta")
        dhtml = ""
        if isinstance(delta, (int, float)):
            arrow = "▲" if delta >= 0 else "▼"
            dhtml = f'<div class="delta {"up" if delta>=0 else "down"}">{arrow} {abs(delta)}%</div>'
        return (f'<div class="{cls} metric">{head}<div class="val">{_esc(val)}'
                f'<span class="unit"> {_esc(unit)}</span></div>{dhtml}</div>')

    if wtype == "table":
        cols = w.get("columns", [])
        rows = w.get("rows", [])
        th = "".join(f"<th>{_esc(c)}</th>" for c in cols)
        trs = "".join("<tr>" + "".join(f"<td>{_esc(c)}</td>" for c in r) + "</tr>" for r in rows)
        return f'<div class="{cls}">{head}<table><thead><tr>{th}</tr></thead><tbody>{trs}</tbody></table></div>'

    if wtype == "chart":
        chart = w.get("chart", "line")
        labels = w.get("labels", [])
        series = w.get("series", [])
        palette = ["#4f46e5", "#16a34a", "#ea580c", "#0891b2", "#db2777"]
        ds = [{"label": s.get("name", f"S{i+1}"), "data": s.get("data", []),
               "borderColor": palette[i % len(palette)],
               "backgroundColor": palette[i % len(palette)] + "55",
               "tension": 0.3} for i, s in enumerate(series)]
        cfg = {"type": chart, "data": {"labels": labels, "datasets": ds},
               "options": {"responsive": True,
                           "plugins": {"legend": {"display": len(ds) > 1}}}}
        return (f'<div class="{cls}">{head}<canvas id="c{idx}"></canvas>'
                f'<script>new Chart(document.getElementById("c{idx}"),{json.dumps(cfg)});</script></div>')

    if wtype == "text":
        return f'<div class="{cls}">{head}<div>{_esc(w.get("text",""))}</div></div>'

    return f'<div class="{cls}">{head}<pre>{_esc(json.dumps(w, indent=2))}</pre></div>'


def _page(title, body, with_chartjs=False):
    cdn = ('<script src="https://cdn.jsdelivr.net/npm/chart.js@4.4.1/dist/chart.umd.min.js"></script>'
           if with_chartjs else "")
    return HTMLResponse(
        f'<!doctype html><html lang="en"><head><meta charset="utf-8">'
        f'<meta name="viewport" content="width=device-width,initial-scale=1">'
        f'<title>{_esc(title)}</title>{cdn}<style>{CSS}</style></head>'
        f'<body><div class="wrap">{body}'
        f'<div class="foot">Agent Dashboards · updated live via API</div></div></body></html>')


@app.get("/", response_class=HTMLResponse)
def index():
    ds = list(_store["dashboards"].values())
    if not ds:
        body = ('<h1>Agent Dashboards</h1><p class="sub">No dashboards yet.</p>'
                '<div class="empty">Create one with <code>POST /api/dashboards</code></div>')
        return _page("Agent Dashboards", body)
    cards = "".join(
        f'<a href="/d/{_esc(d["id"])}"><div class="card"><h3>{_esc(d["id"])}</h3>'
        f'<div style="font-size:18px;font-weight:600">{_esc(d["title"])}</div>'
        f'<div class="sub" style="margin:6px 0 0">{len(d.get("widgets",[]))} widgets · '
        f'{_esc((d.get("updated_at") or "")[:19])}</div></div></a>'
        for d in sorted(ds, key=lambda x: x["id"]))
    body = (f'<h1>Agent Dashboards</h1><p class="sub">{len(ds)} dashboard(s)</p>'
            f'<div class="grid idx">{cards}</div>')
    return _page("Agent Dashboards", body)


@app.get("/d/{dash_id}", response_class=HTMLResponse)
def render_dashboard(dash_id: str):
    d = _store["dashboards"].get(dash_id)
    if not d:
        return _page("Not found", f'<h1>404</h1><p class="sub">No dashboard "{_esc(dash_id)}".</p>'
                     '<p><a href="/">← all dashboards</a></p>')
    data = d.get("data", {})
    widgets = d.get("widgets", [])
    has_chart = any((_effective(w, data).get("type") or "") == "chart" for w in widgets)
    cards = "".join(_render_widget(w, data, i) for i, w in enumerate(widgets)) \
        or '<div class="empty">No widgets yet.</div>'
    body = (f'<p class="sub" style="margin-bottom:2px"><a href="/">← all dashboards</a></p>'
            f'<h1>{_esc(d["title"])}</h1>'
            f'<p class="sub">updated {_esc((d.get("updated_at") or "")[:19])}</p>'
            f'<div class="grid">{cards}</div>')
    return _page(d["title"], body, with_chartjs=has_chart)