#!/usr/bin/env bash
# The spill-over router of tools/build-remote.sh (lib.sh bs_route_spill; the founder, 7 October 2026, 15:02 UK: build-1 at load 139 with a
# queue of 1 h 40 min while build-2 sat at 4.5 with free slots). The class is a preference: a job goes to its class's box unless
# that box has no free slot or its 1-minute load is above 80 (was 64), in which case it goes to the other box when that one qualifies, else
# it queues on its own box. This check feeds the router fixed box states through BS_ROUTE_STATE_<n> (no ssh) and host files in a
# scratch directory, and compares the chosen box and the spilled flag for the known cases: a held build-1 selects build-2, a free
# build-1 selects build-1, an overloaded build-1 spills, a held build-2 sends a suite to build-1, two full boxes queue on the
# class's own box, a box without a host file is never chosen, a build-1 that is down spills.
#
#   tools/ci/route-spill-check.sh              # exit 1 with the case that resolved wrongly (the check IS its self-test)
set -euo pipefail
cd "$(dirname "$0")/../.."
t=$(mktemp -d); trap 'rm -rf "$t"' EXIT
printf 'build@10.0.0.1\n' > "$t/hosts"; printf 'build@10.0.0.2\n' > "$t/hosts-2"   # box 3 absent on purpose
export IGNEUM_BUILD_HOST_FILE="$t/hosts"
fail=0
expect() {   # <case> <class> <want box> <want spilled> ; the states come from the environment
  local name="$1" class="$2" wbox="$3" wsp="$4" out
  out=$(bash -c '. infra/build-server/lib.sh; bs_route_spill "$1" >/dev/null 2>&1; printf "%s %s" "$BS_ROUTE_BOX" "$BS_ROUTE_SPILLED"' _ "$class" 2>/dev/null)
  if [ "$out" = "$wbox $wsp" ]; then echo "route-spill: $name: $class -> box $wbox spilled=$wsp"
  else echo "route-spill: $name: $class resolved to '$out', expected 'box $wbox spilled=$wsp'" >&2; fail=1; fi
}
BS_ROUTE_STATE_1="free=0 slots=2 load1=30" BS_ROUTE_STATE_2="free=3 slots=3 load1=5"  expect "a held build-1 selects build-2"            build 2 1
BS_ROUTE_STATE_1="free=1 slots=2 load1=20" BS_ROUTE_STATE_2="free=3 slots=3 load1=5"  expect "a free build-1 selects build-1"            build 1 0
BS_ROUTE_STATE_1="free=2 slots=2 load1=95" BS_ROUTE_STATE_2="free=3 slots=3 load1=5"  expect "an overloaded build-1 spills"              build 2 1
BS_ROUTE_STATE_1="free=0 slots=2 load1=30" BS_ROUTE_STATE_2="free=3 slots=3 load1=5"  expect "a gate spills like a build"                gate 2 1
BS_ROUTE_STATE_1="free=1 slots=2 load1=5"  BS_ROUTE_STATE_2="free=0 slots=3 load1=10" expect "a held build-2 sends a suite to build-1"   suite 1 1
BS_ROUTE_STATE_1="free=1 slots=2 load1=5"  BS_ROUTE_STATE_2="free=1 slots=3 load1=120" expect "an overloaded build-2 sends a bench away"  bench 1 1
BS_ROUTE_STATE_1="free=2 slots=2 load1=5"  BS_ROUTE_STATE_2="free=2 slots=3 load1=10" expect "a free build-2 keeps its suite"            suite 2 0
BS_ROUTE_STATE_1="free=0 slots=2 load1=80" BS_ROUTE_STATE_2="free=0 slots=3 load1=90" expect "two full boxes queue a build on build-1"   build 1 0
BS_ROUTE_STATE_1="free=0 slots=2 load1=80" BS_ROUTE_STATE_2="free=0 slots=3 load1=90" expect "two full boxes queue a suite on build-2"   suite 2 0
BS_ROUTE_STATE_1="down"                    BS_ROUTE_STATE_2="free=3 slots=3 load1=5"  expect "a build-1 that is down spills"             build 2 1
BS_ROUTE_STATE_1="free=1 slots=2 load1=5"  BS_ROUTE_STATE_2="free=3 slots=3 load1=5"  expect "a proving class with no box 3 prefers box 1" prove 1 0
BS_ROUTE_STATE_1="free=0 slots=2 load1=5"  BS_ROUTE_STATE_2="free=3 slots=3 load1=5"  expect "a proving class spills to box 2 when box 1 is held" prove 2 1
BS_ROUTE_STATE_1="free=1 slots=2 load1=80" BS_ROUTE_STATE_2="free=3 slots=3 load1=5"  expect "load exactly 80 is under the line"         build 1 0
BS_ROUTE_STATE_1="free=2 slots=2 load1=70" BS_ROUTE_STATE_2="free=3 slots=3 load1=5"  expect "load 70 stays on build-1 (the line is 80)"   build 1 0
# the ssh path itself under the hook's shell (/bin/bash is 3.2 on the Mac; the pool lane found `BS_SSH_OPTS[@]: unbound variable`
# at the first unpinned route, 7 Oct 2026): a host file pointing at a port nothing answers on must read "down" in a few seconds,
# not die on an unset array
printf 'build@127.0.0.1\n' > "$t/hosts"
out=$(IGNEUM_BUILD_KEY="$t/no-such-key" /bin/bash -c '. infra/build-server/lib.sh; bs_box_state 1' 2>&1 || true)
if [ "$out" = down ]; then echo "route-spill: the ssh probe under /bin/bash $(/bin/bash -c 'echo $BASH_VERSION') reads an unreachable box as down"
else echo "route-spill: the ssh probe under /bin/bash failed: '$out' (expected 'down')" >&2; fail=1; fi
[ "$fail" = 0 ] && echo "route-spill: the class is a preference; a full or overloaded box hands the job to the other one"
exit $fail