#!/usr/bin/env bash
# Usage: scripts/check-progression.sh <js|scala|fsharp>
# Progression checkpoint: for each module N (that has tests in the track), build a temp copy where src/ holds the
# reference solutions of modules <= N and the untouched student stubs for the rest, then run the tests of modules
# M01..MN. All must pass: this proves a student who has finished module N has a green suite up to N, and that
# no earlier solution secretly depends on a later one. The optional module 07b sits between 07 and 08.
set -uo pipefail
track="${1:?usage: check-progression.sh <js|scala|fsharp>}"
repo="$(cd "$(dirname "$0")/.." && pwd)"
export PATH="$HOME/.dotnet:$HOME/.local/bin:$PATH"

# Module -> files (relative to src/ and solutions/) that the module introduces. A directory entry copies it whole.
files_for() {
  case "$track:$1" in
    js:01)     echo "util.js todo.js" ;;
    js:02)     echo "model.js" ;;
    js:03)     echo "rules.js" ;;
    js:04)     echo "random.js spawn.js state.js" ;;
    js:05)     echo "game.js" ;;
    js:06)     echo "view.js" ;;
    js:07)     echo "io.js" ;;
    js:07b)    echo "safeio.js" ;;  # optional module 7b
    js:08)     echo "stream.js" ;;
    js:09)     echo "input.js app.js runtime.js browser.js main.js" ;;
    js:10)     echo "replay.js" ;;  # also edits game/input/stream/app/io/runtime/browser, already included by m05-m09
    js:11)     echo "pong" ;;
    js:12)     echo "check.js" ;;
    js:13)     echo "life" ;;
    scala:01)  echo "Util.scala" ;;
    scala:02)  echo "Model.scala" ;;
    scala:03)  echo "Rules.scala" ;;
    scala:04)  echo "Random.scala Spawn.scala State.scala" ;;
    scala:05)  echo "Game.scala" ;;
    scala:06)  echo "View.scala" ;;
    scala:07)  echo "IO.scala" ;;
    scala:07b) echo "SafeIO.scala" ;;
    scala:08)  echo "Stream.scala" ;;
    scala:09)  echo "Input.scala App.scala Runtime.scala" ;;
    scala:10)  echo "Replay.scala" ;;
    scala:11)  echo "pong" ;;
    scala:12)  echo "Check.scala" ;;
    scala:13)  echo "life" ;;
    fsharp:01) echo "Util.fs" ;;  # Snake.fsproj lists every file from the start and is identical in both trees
    fsharp:02) echo "Model.fs" ;;
    fsharp:03) echo "Rules.fs" ;;
    fsharp:04) echo "Random.fs Spawn.fs State.fs" ;;
    fsharp:05) echo "Game.fs" ;;
    fsharp:06) echo "View.fs" ;;
    fsharp:07) echo "IO.fs" ;;
    fsharp:07b) echo "SafeIO.fs" ;;
    fsharp:08) echo "Stream.fs" ;;
    fsharp:09) echo "Input.fs App.fs Runtime.fs" ;;
    fsharp:10) echo "Replay.fs" ;;
    fsharp:11) echo "Pong" ;;
    fsharp:12) echo "Check.fs" ;;
    fsharp:13) echo "Life" ;;
    *) echo "" ;;
  esac
}

case "$track" in
  js)     has() { compgen -G "$repo/js/test/m$1-*.test.js" >/dev/null; } ;;
  scala)  has() { compgen -G "$repo/scala/test/M$1*.test.scala" >/dev/null; } ;;
  fsharp) has() { compgen -G "$repo/fsharp/tests/M$1*.fs" >/dev/null; } ;;
  *) echo "unknown track: $track" >&2; exit 2 ;;
esac

# Modules in course order. "07b" (optional) comes after 07: order is position in this list, not numeric value.
modules="01 02 03 04 05 06 07 07b 08 09 10 11 12 13"

# Scala's `./test.sh M07` (munit glob "*M07*") and F#'s (Expecto --filter-test-list, a substring) also select the
# M07b tests, unlike JS's "m07-*" glob. Before module 07b is reached its tests must not run, so delete them from
# the temp copy (and, for F#, their line in tests/Snake.Tests.fsproj; Expecto finds test lists by attribute).
drop_tests() {
  case "$track" in
    scala)  rm -f "$tmp"/scala/test/M"$1"*.test.scala ;;
    fsharp) for f in "$tmp"/fsharp/tests/M"$1"*.fs; do
              [ -e "$f" ] || continue
              rm -f "$f"; sed -i "/Include=\"$(basename "$f")\"/d" "$tmp/fsharp/tests/Snake.Tests.fsproj"
            done ;;
  esac
}

status=0
for n in $modules; do
  has "$n" || continue
  tmp="$(mktemp -d)"
  tar -C "$repo" --exclude=.git --exclude=node_modules --exclude=bin --exclude=obj \
      --exclude=.scala-build --exclude=.bsp --exclude=.superpowers -cf - . | tar -C "$tmp" -xf -
  reached=""; past=0
  for m in $modules; do
    if [ $past -eq 1 ]; then   # a later module: drop its tests if a reached module's tag is a prefix of its tag
      for r in $reached; do [[ "$m" == "$r"?* ]] && drop_tests "$m"; done
      continue
    fi
    for f in $(files_for "$m"); do
      [ -e "$tmp/$track/solutions/$f" ] || continue   # module not (yet) present in this track
      rm -rf "$tmp/$track/src/$f"
      cp -r "$tmp/$track/solutions/$f" "$tmp/$track/src/$f"
    done
    reached="$reached $m"
    [ "$m" = "$n" ] && past=1
  done
  ok=1
  for m in $reached; do
    has "$m" || continue
    if ! out="$(cd "$tmp/$track" && ./test.sh "M$m" 2>&1)"; then
      echo "checkpoint M$n: FAIL (M$m tests fail with solutions up to M$n)"
      echo "$out" | tail -40
      ok=0; status=1; break
    fi
  done
  [ $ok -eq 1 ] && echo "checkpoint M$n: ok (M01..M$n pass)"
  rm -rf "$tmp"
done
exit $status