Derive Final Four paths from game graph

[mateu]

What: Replace hardcoded Final Four and regional-winner game IDs with graph-derived bracket structure data.

Why: Mission focus was issue #18 (reduce hardcoded bracket structure). Pulling paths from game_graph avoids brittle assumptions when bracket IDs or shape change.

How: Added Bracket::Service::BracketStructure to derive championship, semifinal, and regional-final mappings from graph ancestry; wired BracketValidator and Final4 controller to this service; updated validator tests to use derived IDs and added a dedicated structure test.

Testing: script/test-env.sh prove -lv t/bracket_validator.t t/bracket_structure.t and script/test-env.sh prove -lr t.

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Quality Report

Changes: 5 files changed, 199 insertions(+), 43 deletions(-)

Code scan: clean

Tests: failed (FAILED)

Branch hygiene: clean

Generated by Kōan post-mission quality pipeline

[Copilot]

Pull request overview

This PR reduces hardcoded bracket-structure assumptions by deriving Final Four and regional-winner game IDs from game_graph relationships, then wiring that derived structure into validation and Final4 UI flow.

Changes:

• Added Bracket::Service::BracketStructure to compute championship, semifinal, and regional-final mappings from graph ancestry.
• Updated BracketValidator and Final4 controller to use graph-derived Final Four / regional-winner game IDs instead of hardcoded constants.
• Updated validator tests to seed/validate Final Four picks using derived IDs and added a dedicated structure test.

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
lib/Bracket/Service/BracketStructure.pm	New service that derives championship/semifinal/final4 and region-winner games from GameGraph + team regions.
lib/Bracket/Service/BracketValidator.pm	Replaces hardcoded Final Four game allowlist with IDs returned by BracketStructure.
lib/Bracket/Controller/Final4.pm	Replaces hardcoded regional-winner game IDs with graph-derived mapping for stashing region picks.
t/bracket_validator.t	Updates Final Four seeding/validation to rely on derived bracket structure.
t/bracket_structure.t	Adds regression test asserting derived structure matches expected fixture graph.

[Copilot]

%region_for_game is being used both as the recursion cache for _regions_for_game and as the scalar region-id mapping. When _regions_for_game returns 0 or >1 regions for a “regional final” game, the first pass skips setting a scalar, but the cache entry is still an ARRAY ref; the second pass will treat that ARRAY ref as a defined region id and add a bogus key like ARRAY(0x...) to region_winner_games_by_region. Use a separate cache hash from the scalar mapping, or explicitly ignore non-scalar cached values here (e.g., skip if ref $region_id).

Suggested change

	next if !defined $region_id;
	next if !defined $region_id;
	next if ref $region_id;

[Copilot]

In _regions_for_game’s base case, this loops through GameTeamGraph rows and performs a Team->find per slot, which creates an avoidable N+1 query pattern. Consider fetching all needed teams in one query (and prefetching region) or restructuring to avoid per-slot find calls.

Suggested change

	foreach my $slot (@slots) {
	my $team = $schema->resultset('Team')->find({ id => $slot->team });
	next if !$team || !$team->region;
	$regions{$team->region->id} = 1;
	}
	# Avoid N+1 queries: fetch all teams (with regions) for these slots in a single query.
	my @team_ids = map { $_->team } @slots;
	if (@team_ids) {
	my %teams_by_id = map { $_->id => $_ }
	$schema->resultset('Team')->search(
	{ id => { -in => \@team_ids } },
	{ prefetch => 'region' },
	)->all;
	foreach my $slot (@slots) {
	my $team = $teams_by_id{$slot->team};
	next if !$team || !$team->region;
	$regions{$team->region->id} = 1;
	}
	}

[mateu]

Superseded by #29, which has now been squashed and merged. Closing this predecessor PR to keep the active history clean.

[mateu]

Superseded by merged #29.