import logging

from fastapi import APIRouter, Depends, Header, HTTPException, Query, Request
from sqlalchemy import select
from sqlalchemy.ext.asyncio import AsyncSession

from app.database import get_db
from app.models import BotTrade, Subscription, iso_utc
from app.schemas import (
    BotTrade as BotTradeSchema,
    UserResponse,
    UserSettings,
    SetApiKeyRequest,
    SetApiKeyResponse,
    SetSettingsRequest,
)
from app.services.crypto import encrypt_api_key
from app.services.signed_request import verify_signed_request

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

# Action names — must match frontend exactly (used in the signed message)
ACTION_SET_API_KEY = "set_hl_api_key"
ACTION_SET_SETTINGS = "set_settings"
ACTION_VIEW_USER = "view_user"


def _trade_to_schema(trade: BotTrade) -> BotTradeSchema:
    return BotTradeSchema(
        id=trade.id,
        asset=trade.asset,
        side=trade.side,
        entry_price=trade.entry_price,
        exit_price=trade.exit_price or 0.0,
        pnl_usd=trade.pnl_usd or 0.0,
        hold_seconds=trade.hold_seconds or 0,
        trigger_post_id=trade.trigger_post_id or 0,
        opened_at=iso_utc(trade.opened_at) or "",
        closed_at=iso_utc(trade.closed_at) or "",
    )


@router.put("/user/{wallet}/hl-api-key", response_model=SetApiKeyResponse)
async def set_hl_api_key(
    wallet: str,
    body: SetApiKeyRequest,
    db: AsyncSession = Depends(get_db),
):
    wallet = wallet.lower().strip()
    if wallet != body.wallet.lower().strip():
        raise HTTPException(400, "Wallet mismatch between path and body")

    api_key = body.api_key.strip()
    if not api_key.startswith("0x") or len(api_key) != 66:
        raise HTTPException(422, "Invalid API key format — must be a 0x-prefixed 64-char hex string")

    # Signature binds to the full payload (including api_key) so a leaked sig
    # can't be reused to change the key.
    verify_signed_request(
        action=ACTION_SET_API_KEY,
        wallet=wallet,
        timestamp_ms=body.timestamp,
        signature=body.signature,
        body={"api_key": api_key},
    )

    result = await db.execute(select(Subscription).where(Subscription.wallet_address == wallet))
    sub = result.scalar_one_or_none()
    if sub is None:
        raise HTTPException(404, "Wallet not subscribed. Subscribe first.")

    sub.hl_api_key = encrypt_api_key(api_key)
    await db.commit()

    masked = f"...{api_key[-6:]}"
    logger.info("HL API key updated for wallet %s (masked: %s)", wallet, masked)
    return SetApiKeyResponse(status="ok", masked_key=masked)


@router.get("/user/{wallet}/public")
async def get_user_public(wallet: str, db: AsyncSession = Depends(get_db)):
    """No-auth endpoint returning only boolean state. Safe to call on every
    page load to decide whether to show the Subscribe/API-key UI."""
    wallet = wallet.lower().strip()
    result = await db.execute(select(Subscription).where(Subscription.wallet_address == wallet))
    sub = result.scalar_one_or_none()
    if sub is None:
        return {"wallet_address": wallet, "active": False, "hl_api_key_set": False}
    return {
        "wallet_address": wallet,
        "active": sub.active,
        "hl_api_key_set": bool(sub.hl_api_key),
    }


@router.get("/user/{wallet}", response_model=UserResponse)
async def get_user(
    wallet: str,
    ts: int = Query(..., description="Signed timestamp (ms)"),
    sig: str = Query(..., description="EIP-191 signature"),
    db: AsyncSession = Depends(get_db),
):
    wallet = wallet.lower().strip()

    # Require a fresh signed timestamp from the owner — stops wallet-enumeration
    # and trade-history leakage. Frontend re-signs ~every 5 min via sessionStorage.
    verify_signed_request(
        action=ACTION_VIEW_USER,
        wallet=wallet,
        timestamp_ms=ts,
        signature=sig,
        body=None,
        allow_replay=True,  # idempotent GET — allow sessionStorage caching for UX
    )

    result = await db.execute(select(Subscription).where(Subscription.wallet_address == wallet))
    sub = result.scalar_one_or_none()
    if sub is None:
        raise HTTPException(404, "Wallet not found")

    trades_result = await db.execute(
        select(BotTrade)
        .where(BotTrade.wallet_address == wallet)
        .order_by(BotTrade.opened_at.desc())
        .limit(50)
    )
    trades = trades_result.scalars().all()

    hl_api_key_set = bool(sub.hl_api_key)
    # Never return the encrypted blob or any decrypted key. The masked hint
    # shown to the user is derived lazily and only from the last 6 chars of
    # the stored blob's sha-hash, not the plaintext.
    if hl_api_key_set:
        import hashlib
        masked = "..." + hashlib.sha256(sub.hl_api_key.encode()).hexdigest()[-6:]
    else:
        masked = None

    return UserResponse(
        wallet_address=sub.wallet_address,
        active=sub.active,
        subscribed_at=iso_utc(sub.subscribed_at),
        hl_api_key_set=hl_api_key_set,
        hl_api_key_masked=masked,
        trades=[_trade_to_schema(t) for t in trades],
        settings=UserSettings(
            leverage=sub.leverage,
            position_size_usd=sub.position_size_usd,
            take_profit_pct=sub.take_profit_pct,
            stop_loss_pct=sub.stop_loss_pct,
            min_confidence=sub.min_confidence,
            daily_budget_usd=sub.daily_budget_usd,
            active_from=iso_utc(sub.active_from),
            active_until=iso_utc(sub.active_until),
        ),
    )


@router.put("/user/{wallet}/settings", response_model=UserSettings)
async def set_user_settings(
    wallet: str,
    request: Request,
    db: AsyncSession = Depends(get_db),
):
    wallet = wallet.lower().strip()
    # Read raw JSON FIRST — the frontend signs the payload exactly as it's
    # serialized in JSON (e.g. `5` stays `5`, not `5.0`). If we let Pydantic
    # coerce ints→floats first, the server-side hash won't match the client's.
    raw = await request.json()
    raw_settings = raw.get("settings")
    if not isinstance(raw_settings, dict):
        raise HTTPException(422, "Missing settings block")

    # Now validate with Pydantic
    body = SetSettingsRequest(**raw)
    if wallet != body.wallet.lower().strip():
        raise HTTPException(400, "Wallet mismatch")

    s = body.settings
    if not (1 <= s.leverage <= 50):
        raise HTTPException(422, "leverage must be 1–50")
    if not (5 <= s.position_size_usd <= 10000):
        raise HTTPException(422, "position_size_usd must be $5–$10,000")
    # Take-profit, stop-loss and daily budget are now MANDATORY — the bot won't
    # run without them, so we reject null here and force the client to supply values.
    if s.take_profit_pct is None or not (0.1 <= s.take_profit_pct <= 50):
        raise HTTPException(422, "take_profit_pct is required (0.1–50)")
    if s.stop_loss_pct is None or not (0.1 <= s.stop_loss_pct <= 50):
        raise HTTPException(422, "stop_loss_pct is required (0.1–50)")
    if not (0 <= s.min_confidence <= 100):
        raise HTTPException(422, "min_confidence must be 0–100")
    if s.daily_budget_usd is None or not (0 < s.daily_budget_usd <= 100000):
        raise HTTPException(422, "daily_budget_usd is required (>0, ≤100,000)")

    # Parse schedule (ISO strings → naive-UTC datetimes). Either both or neither.
    from datetime import datetime as _dt, timezone as _tz

    def _parse_iso_utc(v):
        if v is None:
            return None
        try:
            # Accept "...Z" or "+00:00" forms
            dt = _dt.fromisoformat(v.replace("Z", "+00:00"))
            if dt.tzinfo is not None:
                dt = dt.astimezone(_tz.utc).replace(tzinfo=None)
            return dt
        except Exception:
            raise HTTPException(422, f"invalid ISO datetime: {v!r}")

    af = _parse_iso_utc(s.active_from)
    au = _parse_iso_utc(s.active_until)
    if (af is None) != (au is None):
        raise HTTPException(422, "active_from and active_until must be set together or both empty")
    if af is not None and au is not None and au <= af:
        raise HTTPException(422, "active_until must be after active_from")

    # Hash the RAW dict (matches what frontend signed)
    verify_signed_request(
        action=ACTION_SET_SETTINGS,
        wallet=wallet,
        timestamp_ms=body.timestamp,
        signature=body.signature,
        body=raw_settings,
    )

    result = await db.execute(select(Subscription).where(Subscription.wallet_address == wallet))
    sub = result.scalar_one_or_none()
    if sub is None:
        raise HTTPException(404, "Wallet not subscribed")

    sub.leverage = s.leverage
    sub.position_size_usd = s.position_size_usd
    sub.take_profit_pct = s.take_profit_pct
    sub.stop_loss_pct = s.stop_loss_pct
    sub.min_confidence = s.min_confidence
    sub.daily_budget_usd = s.daily_budget_usd
    sub.active_from = af
    sub.active_until = au
    await db.commit()
    logger.info("Settings updated for %s: %s", wallet, s.model_dump())
    return s