import { Form, Link } from "react-router";
import type { Route } from "./+types/admin.sports-seasons.$id.events.$eventId.bracket";
import { loader, action } from "./admin.sports-seasons.$id.events.$eventId.bracket.server";
import { Button } from "~/components/ui/button";
import { Input } from "~/components/ui/input";
import { Label } from "~/components/ui/label";
import {
  Card,
  CardContent,
  CardDescription,
  CardHeader,
  CardTitle,
} from "~/components/ui/card";
import {
  Select,
  SelectContent,
  SelectItem,
  SelectTrigger,
  SelectValue,
} from "~/components/ui/select";
import { ArrowLeft, Plus, Trophy } from "lucide-react";
import {
  Table,
  TableBody,
  TableCell,
  TableHead,
  TableHeader,
  TableRow,
} from "~/components/ui/table";

export { loader, action };

export default function EventBracket({
  loaderData,
  actionData,
}: Route.ComponentProps) {
  const { sportsSeason, event, participants, matches } = loaderData;

  // Group matches by round
  const matchesByRound: Record<string, typeof matches> = {};
  for (const match of matches) {
    if (!matchesByRound[match.round]) {
      matchesByRound[match.round] = [];
    }
    matchesByRound[match.round].push(match);
  }

  const rounds = ["Quarterfinals", "Semifinals", "Finals"];
  const availableRounds = rounds.filter(r => matchesByRound[r]);

  // Get participants not yet in any match
  const participantsInMatches = new Set(
    matches.flatMap(m => [m.participant1Id, m.participant2Id].filter(Boolean))
  );
  const availableParticipants = participants.filter(
    (p: { id: string }) => !participantsInMatches.has(p.id)
  );

  return (
    <div className="p-8">
      <div className="max-w-6xl mx-auto">
        <div className="mb-6">
          <Button variant="ghost" size="sm" asChild className="mb-2">
            <Link to={`/admin/sports-seasons/${sportsSeason.id}/events/${event.id}`}>
              <ArrowLeft className="mr-2 h-4 w-4" />
              Back to Event
            </Link>
          </Button>
          <div className="flex items-center justify-between">
            <div>
              <h1 className="text-3xl font-bold">Playoff Bracket</h1>
              <p className="text-muted-foreground mt-1">
                {event.name} - {sportsSeason.sport.name} {sportsSeason.name}
              </p>
            </div>
          </div>
        </div>

        <div className="space-y-6">
          {actionData?.error && (
            <div className="bg-destructive/15 text-destructive px-4 py-3 rounded-md text-sm">
              {actionData.error}
            </div>
          )}

          {actionData?.success && (
            <div className="bg-green-500/15 text-green-700 dark:text-green-400 px-4 py-3 rounded-md text-sm">
              {actionData.success}
            </div>
          )}

          {/* Generate Bracket Form */}
          {matches.length === 0 && (
            <Card>
              <CardHeader>
                <CardTitle>Generate Bracket</CardTitle>
                <CardDescription>
                  Create the bracket structure for this playoff event
                </CardDescription>
              </CardHeader>
              <CardContent>
                <Form method="post" className="space-y-4">
                  <input type="hidden" name="intent" value="generate-bracket" />

                  <div className="space-y-2">
                    <Label htmlFor="bracketSize">Bracket Size</Label>
                    <Select name="bracketSize" defaultValue="8" required>
                      <SelectTrigger id="bracketSize">
                        <SelectValue />
                      </SelectTrigger>
                      <SelectContent>
                        <SelectItem value="4">4 teams (Semifinals + Finals)</SelectItem>
                        <SelectItem value="8">8 teams (Quarterfinals + Semifinals + Finals)</SelectItem>
                      </SelectContent>
                    </Select>
                  </div>

                  <div className="space-y-2">
                    <Label>Select Participants (in order)</Label>
                    <p className="text-sm text-muted-foreground">
                      Select {8} participants for the bracket
                    </p>
                    {[...Array(8)].map((_, i) => (
                      <Select key={i} name={`participant${i}`} required>
                        <SelectTrigger>
                          <SelectValue placeholder={`Seed ${i + 1}`} />
                        </SelectTrigger>
                        <SelectContent>
                          {participants.map((participant: { id: string; name: string }) => (
                            <SelectItem key={participant.id} value={participant.id}>
                              {participant.name}
                            </SelectItem>
                          ))}
                        </SelectContent>
                      </Select>
                    ))}
                  </div>

                  <Button type="submit" className="w-full">
                    <Plus className="mr-2 h-4 w-4" />
                    Generate Bracket
                  </Button>
                </Form>
              </CardContent>
            </Card>
          )}

          {/* Bracket Display */}
          {availableRounds.map(round => (
            <Card key={round}>
              <CardHeader>
                <CardTitle>{round}</CardTitle>
                <CardDescription>
                  {matchesByRound[round].length} {matchesByRound[round].length === 1 ? "match" : "matches"}
                </CardDescription>
              </CardHeader>
              <CardContent>
                <Table>
                  <TableHeader>
                    <TableRow>
                      <TableHead className="w-16">Match</TableHead>
                      <TableHead>Participant 1</TableHead>
                      <TableHead>Score</TableHead>
                      <TableHead className="w-24 text-center">vs</TableHead>
                      <TableHead>Score</TableHead>
                      <TableHead>Participant 2</TableHead>
                      <TableHead>Winner</TableHead>
                      <TableHead className="w-32">Actions</TableHead>
                    </TableRow>
                  </TableHeader>
                  <TableBody>
                    {matchesByRound[round].map((match) => (
                      <TableRow key={match.id}>
                        <TableCell className="font-semibold">
                          {match.matchNumber}
                        </TableCell>
                        <TableCell>
                          {match.participant1?.name || "TBD"}
                        </TableCell>
                        <TableCell>
                          {match.participant1Score ? parseFloat(match.participant1Score) : "-"}
                        </TableCell>
                        <TableCell className="text-center text-muted-foreground">
                          vs
                        </TableCell>
                        <TableCell>
                          {match.participant2Score ? parseFloat(match.participant2Score) : "-"}
                        </TableCell>
                        <TableCell>
                          {match.participant2?.name || "TBD"}
                        </TableCell>
                        <TableCell>
                          {match.winner?.name ? (
                            <div className="flex items-center gap-1">
                              <Trophy className="h-4 w-4 text-yellow-500" />
                              {match.winner.name}
                            </div>
                          ) : (
                            "-"
                          )}
                        </TableCell>
                        <TableCell>
                          {!match.isComplete && match.participant1Id && match.participant2Id ? (
                            <Form method="post" className="inline">
                              <input type="hidden" name="intent" value="set-winner" />
                              <input type="hidden" name="matchId" value={match.id} />
                              <Select name="winnerId" required>
                                <SelectTrigger className="h-8 w-full">
                                  <SelectValue placeholder="Set winner" />
                                </SelectTrigger>
                                <SelectContent>
                                  <SelectItem value={match.participant1Id}>
                                    {match.participant1?.name}
                                  </SelectItem>
                                  <SelectItem value={match.participant2Id}>
                                    {match.participant2?.name}
                                  </SelectItem>
                                </SelectContent>
                              </Select>
                              <Button type="submit" size="sm" className="ml-2 h-8">
                                Set
                              </Button>
                            </Form>
                          ) : match.isComplete ? (
                            <span className="text-sm text-muted-foreground">Complete</span>
                          ) : (
                            <span className="text-sm text-muted-foreground">Waiting</span>
                          )}
                        </TableCell>
                      </TableRow>
                    ))}
                  </TableBody>
                </Table>
              </CardContent>
            </Card>
          ))}

          {/* Complete Round Button */}
          {availableRounds.length > 0 && (
            <Card>
              <CardHeader>
                <CardTitle>Complete Round</CardTitle>
                <CardDescription>
                  Finalize the current round and calculate placements
                </CardDescription>
              </CardHeader>
              <CardContent>
                <Form method="post">
                  <input type="hidden" name="intent" value="complete-round" />
                  <div className="space-y-4">
                    <div className="space-y-2">
                      <Label htmlFor="round">Round to Complete</Label>
                      <Select name="round" required>
                        <SelectTrigger id="round">
                          <SelectValue placeholder="Select round" />
                        </SelectTrigger>
                        <SelectContent>
                          {availableRounds.map(round => (
                            <SelectItem key={round} value={round}>
                              {round}
                            </SelectItem>
                          ))}
                        </SelectContent>
                      </Select>
                    </div>
                    <Button type="submit">
                      Complete Round & Calculate Placements
                    </Button>
                  </div>
                </Form>
              </CardContent>
            </Card>
          )}
        </div>
      </div>
    </div>
  );
}