import { useState, useEffect, useRef } from "react";
import { Check, Info, ChevronDown } from "lucide-react";
import { toast } from "sonner";
import { Label } from "~/components/ui/label";
import { Popover, PopoverContent, PopoverTrigger } from "~/components/ui/popover";

type AutodraftMode = "next_pick" | "while_on";

// 4 visible states map to isEnabled + mode + queueOnly:
//   "off"         → isEnabled: false
//   "next_queue"  → isEnabled: true,  mode: "next_pick", queueOnly: true
//   "all_queue"   → isEnabled: true,  mode: "while_on",  queueOnly: true
//   "all_picks"   → isEnabled: true,  mode: "while_on",  queueOnly: false
type AutodraftState = "off" | "next_queue" | "all_queue" | "all_picks";

type OptionConfig = {
  label: string;
  desc: string;
  isEnabled: boolean;
  mode: AutodraftMode;
  queueOnly: boolean;
};

// Record ensures all AutodraftState values are covered — no runtime find() needed
const OPTIONS: Record<AutodraftState, OptionConfig> = {
  off: {
    label: "Off",
    desc: "You pick manually every round.",
    isEnabled: false,
    mode: "next_pick",
    queueOnly: false,
  },
  next_queue: {
    label: "Next in Queue",
    desc: "Autodrafts your next pick from your queue, then turns off.",
    isEnabled: true,
    mode: "next_pick",
    queueOnly: true,
  },
  all_queue: {
    label: "All in Queue",
    desc: "Keeps autodrafting from your queue until it runs out, then turns off automatically.",
    isEnabled: true,
    mode: "while_on",
    queueOnly: true,
  },
  all_picks: {
    label: "All Picks",
    desc: "Keeps autodrafting all your picks. Uses your queue first, then falls back to the highest-ranked undrafted player.",
    isEnabled: true,
    mode: "while_on",
    queueOnly: false,
  },
};

const OPTION_ORDER: AutodraftState[] = ["off", "next_queue", "all_queue", "all_picks"];

// border-l-[3px] is applied to ALL options (transparent when inactive) so the
// content never shifts when the active border color is applied.
function getButtonClassName(state: AutodraftState, isActive: boolean): string {
  if (!isActive) {
    return "border-l-[3px] border-l-transparent text-muted-foreground hover:bg-muted/40";
  }
  if (state === "off") {
    return "border-l-[3px] border-l-muted-foreground/50 text-foreground";
  }
  return "border-l-[3px] border-l-electric bg-electric text-background";
}

function getCheckClassName(state: AutodraftState): string {
  if (state === "off") return "text-muted-foreground";
  return "text-background";
}

function toAutodraftState(
  isEnabled: boolean,
  mode: AutodraftMode,
  queueOnly: boolean
): AutodraftState {
  if (!isEnabled) return "off";
  if (mode === "next_pick") return "next_queue";
  return queueOnly ? "all_queue" : "all_picks";
}

export function getAutodraftLabel(
  isEnabled: boolean,
  mode: AutodraftMode,
  queueOnly: boolean
): string {
  return OPTIONS[toAutodraftState(isEnabled, mode, queueOnly)].label;
}

interface CompactAutodraftBadgeProps {
  isEnabled: boolean;
  mode: AutodraftMode;
  queueOnly: boolean;
  isMyTurn: boolean;
  showChevron?: boolean;
}

export function CompactAutodraftBadge({
  isEnabled,
  mode,
  queueOnly,
  isMyTurn,
  showChevron = false,
}: CompactAutodraftBadgeProps) {
  const state = toAutodraftState(isEnabled, mode, queueOnly);
  const { label } = OPTIONS[state];
  const isOff = state === "off";

  return (
    <div className="flex items-center gap-2">
      <span className="text-xs text-muted-foreground">Autodraft:</span>
      <span
        className={`text-xs font-medium px-2 py-1 rounded flex items-center gap-1 ${
          isOff
            ? "bg-muted text-muted-foreground border border-border"
            : "bg-electric/20 text-electric border border-electric/30"
        }`}
      >
        {label}
        {showChevron && <ChevronDown className="h-3 w-3" />}
      </span>
      {isMyTurn && (
        <span className="text-xs text-amber-accent font-medium">Your turn!</span>
      )}
    </div>
  );
}

interface AutodraftBadgeWithPopoverProps {
  seasonId: string;
  teamId: string;
  isEnabled: boolean;
  mode: AutodraftMode;
  queueOnly: boolean;
  isMyTurn: boolean;
  onUpdate: (isEnabled: boolean, mode: AutodraftMode, queueOnly: boolean) => void;
}

function AutodraftOptions({
  seasonId,
  teamId,
  isEnabled,
  mode,
  queueOnly,
  isMyTurn,
  onUpdate,
}: Omit<AutodraftBadgeWithPopoverProps, "seasonId" | "teamId"> & {
  seasonId: string;
  teamId: string;
}) {
  const [localState, setLocalState] = useState<AutodraftState>(
    toAutodraftState(isEnabled, mode, queueOnly)
  );
  const abortRef = useRef<AbortController | null>(null);

  useEffect(() => {
    setLocalState(toAutodraftState(isEnabled, mode, queueOnly));
  }, [isEnabled, mode, queueOnly]);

  const sendUpdate = async (newState: AutodraftState) => {
    abortRef.current?.abort();
    abortRef.current = new AbortController();

    const option = OPTIONS[newState];

    try {
      const formData = new FormData();
      formData.append("seasonId", seasonId);
      formData.append("teamId", teamId);
      formData.append("isEnabled", option.isEnabled.toString());
      formData.append("mode", option.mode);
      formData.append("queueOnly", option.queueOnly.toString());

      const response = await fetch("/api/autodraft/update", {
        method: "POST",
        body: formData,
        signal: abortRef.current.signal,
      });

      if (response.ok) {
        onUpdate(option.isEnabled, option.mode, option.queueOnly);
        toast.success(
          option.isEnabled ? `Autodraft set to "${option.label}"` : "Autodraft turned off"
        );
      } else {
        setLocalState(toAutodraftState(isEnabled, mode, queueOnly));
        toast.error("Failed to save autodraft settings");
      }
    } catch (error) {
      if (error instanceof Error && error.name === "AbortError") return;
      setLocalState(toAutodraftState(isEnabled, mode, queueOnly));
      toast.error("Failed to save autodraft settings");
    }
  };

  const handleStateChange = (newState: AutodraftState) => {
    if (newState === localState || isMyTurn) return;
    setLocalState(newState);
    sendUpdate(newState);
  };

  const isDisabled = isMyTurn;

  return (
    <div className="flex flex-col rounded-lg border overflow-hidden">
      {OPTION_ORDER.map((state) => {
        const { label } = OPTIONS[state];
        const isActive = localState === state;
        return (
          <button
            key={state}
            type="button"
            disabled={isDisabled}
            onClick={() => handleStateChange(state)}
            className={`w-full py-2.5 px-3 text-left transition-colors border-b last:border-b-0 flex items-center justify-between gap-2 ${getButtonClassName(state, isActive)} ${
              isDisabled ? "opacity-50 cursor-not-allowed" : "cursor-pointer"
            }`}
          >
            <span className="text-xs font-medium">{label}</span>
            {isActive && (
              <Check className={`h-3.5 w-3.5 shrink-0 ${getCheckClassName(state)}`} />
            )}
          </button>
        );
      })}
      {isMyTurn && (
        <p className="text-xs text-muted-foreground mt-2 text-center px-3 py-2">
          You're on the clock!
        </p>
      )}
    </div>
  );
}

export function AutodraftBadgeWithPopover({
  seasonId,
  teamId,
  isEnabled,
  mode,
  queueOnly,
  isMyTurn,
  onUpdate,
}: AutodraftBadgeWithPopoverProps) {
  const [open, setOpen] = useState(false);

  return (
    <div className="flex items-center gap-2">
      <Popover open={open} onOpenChange={setOpen}>
        <PopoverTrigger asChild>
          <button
            type="button"
            className="hover:bg-muted/40 rounded px-2 py-1 -mx-2 -my-1 transition-colors"
          >
            <CompactAutodraftBadge
              isEnabled={isEnabled}
              mode={mode}
              queueOnly={queueOnly}
              isMyTurn={isMyTurn}
              showChevron
            />
          </button>
        </PopoverTrigger>
        <PopoverContent className="w-72 p-0" align="end">
          <AutodraftOptions
            seasonId={seasonId}
            teamId={teamId}
            isEnabled={isEnabled}
            mode={mode}
            queueOnly={queueOnly}
            isMyTurn={isMyTurn}
            onUpdate={onUpdate}
          />
        </PopoverContent>
      </Popover>

      <Popover>
        <PopoverTrigger asChild>
          <button
            type="button"
            className="text-muted-foreground hover:text-foreground transition-colors"
            aria-label="Autodraft options explained"
          >
            <Info className="h-3.5 w-3.5" />
          </button>
        </PopoverTrigger>
        <PopoverContent className="w-72" align="end">
          <p className="text-sm font-semibold mb-2.5">Autodraft Options</p>
          <div className="space-y-2.5">
            {OPTION_ORDER.map((state) => {
              const { label, desc } = OPTIONS[state];
              return (
                <div key={state}>
                  <p className="text-xs font-medium">{label}</p>
                  <p className="text-xs text-muted-foreground">{desc}</p>
                </div>
              );
            })}
          </div>
        </PopoverContent>
      </Popover>
    </div>
  );
}

interface AutodraftSettingsProps {
  seasonId: string;
  teamId: string;
  isEnabled: boolean;
  mode: AutodraftMode;
  queueOnly: boolean;
  isMyTurn: boolean;
  onUpdate: (isEnabled: boolean, mode: AutodraftMode, queueOnly: boolean) => void;
}

export function AutodraftSettings({
  seasonId,
  teamId,
  isEnabled,
  mode,
  queueOnly,
  isMyTurn,
  onUpdate,
}: AutodraftSettingsProps) {
  const [localState, setLocalState] = useState<AutodraftState>(
    toAutodraftState(isEnabled, mode, queueOnly)
  );
  // Holds the abort controller for any in-flight save so rapid selections
  // cancel the previous request rather than racing to update the server.
  const abortRef = useRef<AbortController | null>(null);

  // Sync local state with props when they change (from socket events)
  useEffect(() => {
    setLocalState(toAutodraftState(isEnabled, mode, queueOnly));
  }, [isEnabled, mode, queueOnly]);

  const sendUpdate = async (newState: AutodraftState) => {
    // Cancel any in-flight request before starting a new one
    abortRef.current?.abort();
    abortRef.current = new AbortController();

    const option = OPTIONS[newState];

    try {
      const formData = new FormData();
      formData.append("seasonId", seasonId);
      formData.append("teamId", teamId);
      formData.append("isEnabled", option.isEnabled.toString());
      formData.append("mode", option.mode);
      formData.append("queueOnly", option.queueOnly.toString());

      const response = await fetch("/api/autodraft/update", {
        method: "POST",
        body: formData,
        signal: abortRef.current.signal,
      });

      if (response.ok) {
        onUpdate(option.isEnabled, option.mode, option.queueOnly);
        toast.success(
          option.isEnabled ? `Autodraft set to "${option.label}"` : "Autodraft turned off"
        );
      } else {
        setLocalState(toAutodraftState(isEnabled, mode, queueOnly));
        toast.error("Failed to save autodraft settings");
      }
    } catch (error) {
      // Ignore cancellations — a newer selection has already taken over
      if (error instanceof Error && error.name === "AbortError") return;
      setLocalState(toAutodraftState(isEnabled, mode, queueOnly));
      toast.error("Failed to save autodraft settings");
    }
  };

  const handleStateChange = (newState: AutodraftState) => {
    if (newState === localState || isMyTurn) return;
    setLocalState(newState);
    sendUpdate(newState);
  };

  const isDisabled = isMyTurn;

  return (
    <div className="border-t pt-4 mt-4">
      {/* Header with info icon inline */}
      <div className="flex items-center gap-1.5 mb-3">
        <Label className="text-sm font-semibold">Autodraft</Label>
        <Popover>
          <PopoverTrigger asChild>
            <button
              type="button"
              className="text-muted-foreground hover:text-foreground transition-colors"
              aria-label="Autodraft options explained"
            >
              <Info className="h-3.5 w-3.5" />
            </button>
          </PopoverTrigger>
          <PopoverContent className="w-72" align="start">
            <p className="text-sm font-semibold mb-2.5">Autodraft Options</p>
            <div className="space-y-2.5">
              {OPTION_ORDER.map((state) => {
                const { label, desc } = OPTIONS[state];
                return (
                  <div key={state}>
                    <p className="text-xs font-medium">{label}</p>
                    <p className="text-xs text-muted-foreground">{desc}</p>
                  </div>
                );
              })}
            </div>
          </PopoverContent>
        </Popover>
      </div>

      <div className="flex flex-col rounded-lg border overflow-hidden">
        {OPTION_ORDER.map((state) => {
          const { label } = OPTIONS[state];
          const isActive = localState === state;
          return (
            <button
              key={state}
              type="button"
              disabled={isDisabled}
              onClick={() => handleStateChange(state)}
              className={`w-full py-2.5 px-3 text-left transition-colors border-b last:border-b-0 flex items-center justify-between gap-2 ${getButtonClassName(state, isActive)} ${
                isDisabled ? "opacity-50 cursor-not-allowed" : "cursor-pointer"
              }`}
            >
              <span className="text-xs font-medium">{label}</span>
              {isActive && (
                <Check className={`h-3.5 w-3.5 shrink-0 ${getCheckClassName(state)}`} />
              )}
            </button>
          );
        })}
      </div>

      {isMyTurn && (
        <p className="text-xs text-muted-foreground mt-2">You're on the clock!</p>
      )}
    </div>
  );
}