brackt/app/routes/admin.sports-seasons.$id.events.$eventId.bracket.server.ts

import type { Route } from "./+types/admin.sports-seasons.$id.events.$eventId.bracket";
import { redirect } from "react-router";
import { findSportsSeasonById } from "~/models/sports-season";
import { findParticipantsBySportsSeasonId } from "~/models/participant";
import { getScoringEventById, updateScoringEvent } from "~/models/scoring-event";
import {
  findPlayoffMatchesByEventId,
  generateBracketFromTemplate,
  setMatchWinner,
  advanceWinnerTemplate,
  findPlayoffMatchById,
} from "~/models/playoff-match";
import { processPlayoffEvent } from "~/models/scoring-calculator";
import { getBracketTemplate } from "~/lib/bracket-templates";
import { database } from "~/database/context";
import * as schema from "~/database/schema";
import { eq } from "drizzle-orm";

export async function loader({ params }: Route.LoaderArgs) {
  const sportsSeason = await findSportsSeasonById(params.id);

  if (!sportsSeason) {
    throw new Response("Sports season not found", { status: 404 });
  }

  const event = await getScoringEventById(params.eventId);

  if (!event) {
    throw new Response("Event not found", { status: 404 });
  }

  if (event.eventType !== "playoff_game") {
    throw new Response("This event is not a playoff event", { status: 400 });
  }

  const participants = await findParticipantsBySportsSeasonId(params.id);
  const matches = await findPlayoffMatchesByEventId(params.eventId);

  // The matches already include participant relations from the model query
  return {
    sportsSeason: sportsSeason as typeof sportsSeason & {
      sport: { id: string; name: string; type: string; slug: string };
    },
    event,
    participants,
    matches: matches as Array<typeof matches[0] & {
      participant1: { id: string; name: string } | null;
      participant2: { id: string; name: string } | null;
      winner: { id: string; name: string } | null;
      loser: { id: string; name: string } | null;
    }>,
  };
}

export async function action({ request, params }: Route.ActionArgs) {
  const formData = await request.formData();
  const intent = formData.get("intent");

  if (intent === "generate-bracket") {
    const templateId = formData.get("templateId");

    if (typeof templateId !== "string" || !templateId) {
      return { error: "Template ID is required" };
    }

    const template = getBracketTemplate(templateId);
    if (!template) {
      return { error: "Invalid bracket template" };
    }

    const participantIds: string[] = [];

    for (let i = 0; i < template.totalTeams; i++) {
      const participantId = formData.get(`participant${i}`);
      if (typeof participantId !== "string" || !participantId) {
        return { error: `Participant ${i + 1} is required` };
      }
      participantIds.push(participantId);
    }

    // Check for duplicates
    const uniqueParticipants = new Set(participantIds);
    if (uniqueParticipants.size !== participantIds.length) {
      return { error: "Each participant can only be selected once" };
    }

    try {
      await generateBracketFromTemplate(params.eventId, templateId, participantIds);

      // Update the event to store the template ID and scoring start round
      await updateScoringEvent(params.eventId, {
        bracketTemplateId: templateId,
        scoringStartsAtRound: template.scoringStartsAtRound,
      });

      return { success: "Bracket generated successfully" };
    } catch (error) {
      console.error("Error generating bracket:", error);
      return {
        error:
          error instanceof Error
            ? error.message
            : "Failed to generate bracket",
      };
    }
  }

  if (intent === "set-winner") {
    const matchId = formData.get("matchId");
    const winnerId = formData.get("winnerId");

    if (typeof matchId !== "string" || !matchId) {
      return { error: "Match ID is required" };
    }

    if (typeof winnerId !== "string" || !winnerId) {
      return { error: "Winner ID is required" };
    }

    try {
      const match = await findPlayoffMatchById(matchId);
      if (!match) {
        return { error: "Match not found" };
      }

      // Get the event to determine the template
      const event = await getScoringEventById(match.scoringEventId);
      if (!event) {
        return { error: "Event not found" };
      }

      // Determine loser
      const loserId =
        match.participant1Id === winnerId
          ? match.participant2Id
          : match.participant1Id;

      if (!loserId) {
        return { error: "Could not determine loser" };
      }

      // Set the winner
      await setMatchWinner(matchId, winnerId, loserId);

      // Try to advance the winner to the next round using template
      if (event.bracketTemplateId) {
        const template = getBracketTemplate(event.bracketTemplateId);
        if (template) {
          try {
            await advanceWinnerTemplate(matchId, winnerId, template);
          } catch (error) {
            // Only ignore "already filled" errors, re-throw unexpected errors
            if (
              error instanceof Error &&
              error.message.includes("already filled")
            ) {
              console.warn("Match already filled, skipping advancement");
            } else {
              throw error; // Re-throw unexpected errors
            }
          }
        }
      }

      return { success: "Winner set successfully" };
    } catch (error) {
      console.error("Error setting winner:", error);
      return {
        error:
          error instanceof Error ? error.message : "Failed to set winner",
      };
    }
  }

  if (intent === "set-round-winners") {
    const round = formData.get("round");

    if (typeof round !== "string" || !round) {
      return { error: "Round is required" };
    }

    try {
      // Get all winner assignments from form data
      const winnerAssignments: Array<{ matchId: string; winnerId: string }> = [];

      for (const [key, value] of formData.entries()) {
        if (key.startsWith("winner-") && typeof value === "string") {
          const matchId = key.replace("winner-", "");
          winnerAssignments.push({ matchId, winnerId: value });
        }
      }

      if (winnerAssignments.length === 0) {
        return { error: "No winners selected" };
      }

      // Get the event to determine the template
      const event = await getScoringEventById(params.eventId);
      if (!event) {
        return { error: "Event not found" };
      }

      const template = event.bracketTemplateId ? getBracketTemplate(event.bracketTemplateId) : null;

      // Process each winner assignment
      let successCount = 0;
      const errors: string[] = [];

      for (const { matchId, winnerId } of winnerAssignments) {
        try {
          const match = await findPlayoffMatchById(matchId);
          if (!match) {
            errors.push(`Match ${matchId} not found`);
            continue;
          }

          // Determine loser
          const loserId =
            match.participant1Id === winnerId
              ? match.participant2Id
              : match.participant1Id;

          if (!loserId) {
            errors.push(`Could not determine loser for match ${match.matchNumber}`);
            continue;
          }

          // Set the winner
          await setMatchWinner(matchId, winnerId, loserId);

          // Try to advance the winner to the next round using template
          if (template) {
            try {
              await advanceWinnerTemplate(matchId, winnerId, template);
            } catch (error) {
              // Only ignore "already filled" errors
              if (
                error instanceof Error &&
                error.message.includes("already filled")
              ) {
                console.warn("Match already filled, skipping advancement");
              } else {
                throw error;
              }
            }
          }

          successCount++;
        } catch (error) {
          console.error(`Error setting winner for match ${matchId}:`, error);
          errors.push(
            `Match ${matchId}: ${error instanceof Error ? error.message : "Unknown error"}`
          );
        }
      }

      if (errors.length > 0 && successCount === 0) {
        return { error: `Failed to set winners: ${errors.join(", ")}` };
      }

      if (errors.length > 0) {
        return {
          success: `Set ${successCount} winner(s) successfully`,
          error: `Some errors occurred: ${errors.join(", ")}`,
        };
      }

      return { success: `Successfully set ${successCount} winner(s) for ${round}` };
    } catch (error) {
      console.error("Error setting round winners:", error);
      return {
        error:
          error instanceof Error ? error.message : "Failed to set winners",
      };
    }
  }

  if (intent === "complete-round") {
    const round = formData.get("round");

    if (typeof round !== "string" || !round) {
      return { error: "Round is required" };
    }

    try {
      // Get the event and update playoffRound to the completed round
      const event = await getScoringEventById(params.eventId);
      if (!event) {
        return { error: "Event not found" };
      }

      // Verify all matches in this round are complete
      const matches = await findPlayoffMatchesByEventId(params.eventId);

      // Validate that the round exists in this event's matches
      const roundMatches = matches.filter((m) => m.round === round);
      if (roundMatches.length === 0) {
        return { error: `Round "${round}" not found in this bracket` };
      }

      const allComplete = roundMatches.every((m) => m.isComplete);
      if (!allComplete) {
        return { error: `Not all matches in ${round} are complete` };
      }

      // Validate round order: ensure previous rounds are complete
      const { findParticipantResultsBySportsSeasonId } = await import(
        "~/models/participant-result"
      );
      const existingResults = await findParticipantResultsBySportsSeasonId(
        params.id
      );

      if (round === "Finals") {
        // Finals requires Semifinals to be complete (3rd/4th place results exist)
        const hasSemifinalResults = existingResults.some(
          (r) => r.finalPosition === 3 || r.finalPosition === 4
        );
        if (!hasSemifinalResults) {
          return {
            error:
              "Semifinals must be completed before Finals (no 3rd/4th place results found)",
          };
        }
      } else if (round === "Semifinals") {
        // Semifinals requires Quarterfinals to be complete if QF matches exist
        const hasQuarterfinals = matches.some((m) => m.round === "Quarterfinals");
        if (hasQuarterfinals) {
          const hasQuarterfinalsResults = existingResults.some(
            (r) =>
              r.finalPosition === 5 ||
              r.finalPosition === 6 ||
              r.finalPosition === 7 ||
              r.finalPosition === 8
          );
          if (!hasQuarterfinalsResults) {
            return {
              error:
                "Quarterfinals must be completed before Semifinals (no 5th-8th place results found)",
            };
          }
        }
      }

      // Get the sports season to find a fantasy season for scoring rules
      const sportsSeason = await findSportsSeasonById(params.id);
      if (!sportsSeason) {
        return { error: "Sports season not found" };
      }

      // Process the playoff event to calculate placements
      // TODO Phase 2.7: Refactor processPlayoffEvent to use template system
      // For now, we still need to set playoffRound for the old scoring logic
      // even though we removed it from the create event UI
      const db = database();
      await db
        .update(schema.scoringEvents)
        .set({ playoffRound: round, updatedAt: new Date() })
        .where(eq(schema.scoringEvents.id, params.eventId));

      // Get a fantasy season ID for scoring calculation
      const { findSeasonSportsBySportsSeasonId } = await import(
        "~/models/season-sport"
      );
      const seasonSports = await findSeasonSportsBySportsSeasonId(params.id);
      if (seasonSports.length === 0) {
        return {
          error: "No fantasy seasons found for this sports season",
        };
      }

      // Process playoff event to update participant results
      await processPlayoffEvent(params.eventId);

      return {
        success: `${round} completed and placements calculated successfully`,
      };
    } catch (error) {
      console.error("Error completing round:", error);
      return {
        error:
          error instanceof Error ? error.message : "Failed to complete round",
      };
    }
  }

  return { error: "Invalid action" };
}