import logging
import time
import uuid

from fastapi import APIRouter, Depends, HTTPException, Query, Request, Response
from pydantic import BaseModel, Field

from app.bars.models import Timeframe
from app.analysis.levels import Side
from app.analysis.manual_lines import ManualLine
from app.api.deps import require_token

# Everything here needs the token when CHART_AUTH_TOKEN is set. /health and
# /version live in app.api.meta and stay open on purpose.
logger = logging.getLogger(__name__)

router = APIRouter(prefix="/api", dependencies=[Depends(require_token)])


class LineCreate(BaseModel):
    tf: Timeframe
    side: Side
    anchor_t: int
    anchor_p: float
    end_t: int
    end_p: float
    note: str = ""
    hidden: bool = False
    color: str = Field("#65b7cf", pattern=r"^#[0-9a-fA-F]{6}$")
    line_width: int = Field(2, ge=1, le=4)
    cutoff_t: int | None = None
    armed: bool = True


class PriceAlertCreate(BaseModel):
    """A horizontal level typed in rather than drawn.

    Structurally just a manual line with zero slope, so it inherits persistence,
    editing, clustering and — importantly — the rule that a hand-placed level
    alerts regardless of confluence score.
    """

    price: float = Field(gt=0)
    note: str = ""
    tf: Timeframe = Timeframe.D1
    color: str = Field("#e0a34a", pattern=r"^#[0-9a-fA-F]{6}$")
    line_width: int = Field(2, ge=1, le=4)


class LinePatch(BaseModel):
    side: Side | None = None
    note: str | None = None
    hidden: bool | None = None
    color: str | None = Field(None, pattern=r"^#[0-9a-fA-F]{6}$")
    line_width: int | None = Field(None, ge=1, le=4)
    anchor_t: int | None = None
    anchor_p: float | None = None
    slope: float | None = None
    last_t: int | None = None
    cutoff_t: int | None = None
    armed: bool | None = None
    pinned: bool | None = None
    x: float | None = Field(None, ge=0.0, le=1.0)
    y: float | None = Field(None, ge=0.0, le=1.0)
    collapsed: bool | None = None


@router.get("/status")
def status(request: Request):
    runtime = request.app.state.runtime
    return {
        "stream": runtime.stream.status,
        "source": runtime.stream.source.name,
        "delay_minutes": runtime.stream.source.delay_minutes,
        "symbol": runtime.stream.symbol,
        "last_bar_t": runtime.stream.last_bar_t,
        "bars_held": runtime.store.counts(),
        "warm": {tf.value: bool(runtime.store.get(tf)) for tf in Timeframe},
    }


@router.get("/bars")
def bars(request: Request, tf: str = "1m", limit: int = Query(500, ge=1, le=5000)):
    try:
        timeframe = Timeframe(tf)
    except ValueError as exc:
        raise HTTPException(400, "Unknown timeframe") from exc
    values = request.app.state.runtime.store.get(timeframe, limit)
    return {"tf": timeframe.value, "bars": [bar.to_dict() for bar in values]}


@router.get("/levels")
def levels(request: Request, tf: str = "all"):
    values = request.app.state.runtime.levels
    if tf != "all":
        try:
            timeframe = Timeframe(tf)
        except ValueError as exc:
            raise HTTPException(400, "Unknown timeframe") from exc
        values = [level for level in values if level.tf is timeframe]
    return {"levels": [level.to_dict() for level in values]}


@router.get("/confluence")
def confluence(request: Request):
    runtime = request.app.state.runtime
    return {
        "price": runtime.price,
        "clusters": [cluster.to_dict() for cluster in runtime.clusters],
    }


@router.post("/lines", status_code=201)
def create_line(request: Request, payload: LineCreate):
    if payload.end_t == payload.anchor_t:
        raise HTTPException(400, "Line endpoints must have different times")
    line = ManualLine(
        id=f"ml_{uuid.uuid4().hex}",
        tf=payload.tf,
        side=payload.side,
        anchor_t=payload.anchor_t,
        anchor_p=payload.anchor_p,
        slope=(payload.end_p - payload.anchor_p) / (payload.end_t - payload.anchor_t),
        last_t=payload.end_t,
        created_at=int(time.time()),
        note=payload.note,
        hidden=payload.hidden,
        color=payload.color,
        line_width=payload.line_width,
        cutoff_t=payload.cutoff_t,
        armed=payload.armed,
    )
    runtime = request.app.state.runtime
    line = runtime.manual_lines.add(line)
    runtime.rebuild_levels()
    return line.to_level().to_dict()


@router.post("/lines/price", status_code=201)
def create_price_alert(request: Request, payload: PriceAlertCreate):
    runtime = request.app.state.runtime
    now = int(time.time())
    # Side is only used for the label; clustering derives it positionally.
    reference = runtime.price if runtime.price is not None else payload.price
    line = ManualLine(
        id=f"ml_{uuid.uuid4().hex}",
        tf=payload.tf,
        side=Side.RESISTANCE if payload.price >= reference else Side.SUPPORT,
        anchor_t=now,
        anchor_p=payload.price,
        slope=0.0,
        # A horizontal level has no natural end. The span only matters to the
        # fallback geometry; price_at() is constant either way.
        last_t=now + 3600,
        created_at=now,
        note=payload.note,
        color=payload.color,
        line_width=payload.line_width,
    )
    line = runtime.manual_lines.add(line)
    runtime.rebuild_levels()
    return line.to_level().to_dict()


class CommentCreate(BaseModel):
    text: str = Field(min_length=1, max_length=2000)
    # Pinned to a moment on the chart, or floating and always on screen.
    pinned: bool = True
    anchor_t: int | None = None
    anchor_p: float | None = None
    x: float = Field(0.72, ge=0.0, le=1.0)
    y: float = Field(0.12, ge=0.0, le=1.0)
    color: str = Field("#c8992f", pattern=r"^#[0-9a-fA-F]{6}$")
    tf: Timeframe = Timeframe.M1


@router.post("/comments", status_code=201)
def create_comment(request: Request, payload: CommentCreate):
    """A note on the chart. Stored with the lines so it shares their numbering,
    filtering and deletion, but it is never a level — see ManualLineStore.levels.
    """
    runtime = request.app.state.runtime
    now = int(time.time())
    anchored = payload.anchor_t if payload.anchor_t is not None else now
    line = ManualLine(
        id=f"ml_{uuid.uuid4().hex}",
        tf=payload.tf,
        # Side is meaningless for a comment; clustering never sees it.
        side=Side.SUPPORT,
        anchor_t=anchored,
        anchor_p=payload.anchor_p if payload.anchor_p is not None else (runtime.price or 0.0),
        slope=0.0,
        last_t=anchored,
        created_at=now,
        note=payload.text,
        color=payload.color,
        kind="comment",
        pinned=payload.pinned,
        x=payload.x,
        y=payload.y,
        # A comment must never alert, whatever else changes around it.
        armed=False,
    )
    line = runtime.manual_lines.add(line)
    return line.to_dict()


class SnapReport(BaseModel):
    """What the browser computed for one snap, for diagnosing chart geometry."""
    cursor_t: int | None = None
    cursor_p: float | None = None
    cursor_x: float | None = None
    snapped_t: int | None = None
    snapped_p: float | None = None
    bars_held: int | None = None
    first_bar_t: int | None = None
    last_bar_t: int | None = None
    tf: str | None = None
    chart_w: float | None = None
    chart_h: float | None = None
    cursor_y: float | None = None
    # Where the indicator actually landed versus where the price says it should
    # — the only way to tell a wrong answer from a correctly-computed one drawn
    # in the wrong place.
    dot_y: float | None = None
    expected_y: float | None = None
    bar_low_y: float | None = None
    bar_high_y: float | None = None
    note: str | None = None


@router.post("/debug/snap", status_code=204)
def debug_snap(payload: SnapReport):
    """Record one snap sample from a browser running diagnostic mode.

    Chart geometry bugs live in the client, and the browser is usually on a
    different machine from whoever is debugging it — so its own numbers cannot
    be read any other way. Off unless the page is opened with ?diag=1; see
    AGENTS.md. Logged at warning level so it appears without reconfiguring
    uvicorn's log levels.
    """
    logger.warning("SNAPDBG %s", payload.model_dump())
    return Response(status_code=204)


@router.get("/drawings")
def drawings(request: Request):
    """Every drawing, comments included, for the sidebar list."""
    store = request.app.state.runtime.manual_lines
    return {"drawings": [
        {**line.to_dict(), "kind": line.drawing_kind} for line in store.drawings()
    ]}


@router.patch("/lines/{line_id}")
def patch_line(request: Request, line_id: str, payload: LinePatch):
    changes = payload.model_dump(exclude_none=True)
    if changes.get("anchor_t") == changes.get("last_t") and "anchor_t" in changes:
        raise HTTPException(400, "Line endpoints must have different times")
    try:
        line = request.app.state.runtime.manual_lines.update(line_id, changes)
    except KeyError as exc:
        raise HTTPException(404, "Line not found") from exc
    request.app.state.runtime.rebuild_levels()
    # A comment has no level form — returning one would hand the caller a shape
    # that looks like something the confluence engine tracks.
    return line.to_dict() if line.is_comment else line.to_level().to_dict()


@router.delete("/lines/{line_id}", status_code=204)
def delete_line(request: Request, line_id: str):
    try:
        request.app.state.runtime.manual_lines.delete(line_id)
    except KeyError as exc:
        raise HTTPException(404, "Line not found") from exc
    request.app.state.runtime.rebuild_levels()
    return Response(status_code=204)