#!/usr/bin/env bash
# Row 56 deliberate deltas. Outside the seeded data root of byte-check.sh,
# list and show change on purpose where a record links out of the data
# root, a document isn't a JSON object, a run is a regular file, or the
# runs directory can't be read. This prints the baseline and candidate
# output for each such case (first stderr line only) so the change is on
# record. It asserts nothing; the package tests assert the new behaviour.
# Usage: delta-check.sh BASE_TREE CAND_TREE WORK_DIR   (WORK_DIR must not exist)
set -euo pipefail
BASE="$(cd "$1" && pwd)"; CAND="$(cd "$2" && pwd)"; W="$3"
[ ! -e "$W" ] || { echo "delta-check: $W exists" >&2; exit 4; }
mkdir -p "$W"; W="$(cd "$W" && pwd)"
A=r-20260101T000000Z-aaaaaa
RESULT='{"runVersion":1,"taskId":"t-out","status":"succeeded","request":"r","response":"s","provider":"p","model":"m","startedAt":"a","finishedAt":"b","durationMs":1,"exitCode":0,"signal":null}'

root() { # name -> creates W/name/{data,outside}, writes config, echoes data root
  mkdir -p "$W/$1/data" "$W/$1/outside"
  printf '{"configVersion":1,"environment":"development","dataRoot":"%s","execution":{"backend":"docker","provider":"zai","model":"m"}}\n' "$W/$1/data" > "$W/$1/config.json"
  echo "$W/$1/data"
}
run_case() { # name op [arg]
  local name="$1"; shift
  for tree in base cand; do
    local dir="$BASE"; [ "$tree" = cand ] && dir="$CAND"
    local rc=0 out err
    out="$(cd "$dir" && env MOSAIC_CONFIG="$W/$name/config.json" node scripts/mosaic-task.mjs "$@" 2>"$W/$name/$tree.err")" || rc=$?
    err="$(head -1 "$W/$name/$tree.err")"
    printf '  %s: exit %s\n' "$tree" "$rc"
    [ -z "$out" ] || printf '%s\n' "$out" | sed 's/^/    out| /'
    [ -z "$err" ] || printf '    err| %s\n' "$err"
  done
}
hdr() { printf '\n== %s\n' "$*"; }

D="$(root run-link)"; mkdir -p "$D/runs"; printf '%s\n' "$RESULT" > "$W/run-link/outside/result.json"; ln -s "$W/run-link/outside" "$D/runs/$A"
hdr "run directory linked out of the data root: list"; run_case run-link list
hdr "run directory linked out of the data root: show"; run_case run-link show "$A"

D="$(root doc-link)"; mkdir -p "$D/runs/$A"; printf '%s\n' "$RESULT" > "$W/doc-link/outside/result.json"; ln -s "$W/doc-link/outside/result.json" "$D/runs/$A/result.json"
hdr "result.json linked out of the data root: list"; run_case doc-link list
hdr "result.json linked out of the data root: show"; run_case doc-link show "$A"

D="$(root runs-link)"; mkdir -p "$W/runs-link/outside/$A"; printf '%s\n' "$RESULT" > "$W/runs-link/outside/$A/result.json"; ln -s "$W/runs-link/outside" "$D/runs"
hdr "runs directory linked out of the data root: list"; run_case runs-link list
hdr "runs directory linked out of the data root: show"; run_case runs-link show "$A"

D="$(root non-object)"; mkdir -p "$D/runs/$A"; printf '5\n' > "$D/runs/$A/result.json"; printf '[]\n' > "$D/runs/$A/task.json"
hdr "result.json is 5 and task.json is []: list"; run_case non-object list
hdr "result.json is 5 and task.json is []: show"; run_case non-object show "$A"

D="$(root run-file)"; mkdir -p "$D/runs"; printf 'x\n' > "$D/runs/$A"
hdr "run is a regular file: show"; run_case run-file show "$A"

D="$(root loop)"; mkdir -p "$D/runs"; ln -s r-b "$D/runs/$A"; ln -s "$A" "$D/runs/r-b"
hdr "run is a link loop: show"; run_case loop show "$A"

if [ "$(id -u)" != 0 ]; then
  D="$(root unreadable)"; mkdir -p "$D/runs/$A"; chmod 000 "$D/runs"
  hdr "runs directory unreadable: list"; run_case unreadable list
  hdr "runs directory unreadable: show"; run_case unreadable show "$A"
  chmod 755 "$D/runs"
  D="$(root run-unreadable)"; mkdir -p "$D/runs/$A"; printf '%s\n' "$RESULT" > "$D/runs/$A/result.json"; chmod 000 "$D/runs/$A"
  hdr "run directory unreadable: show"; run_case run-unreadable show "$A"
  chmod 755 "$D/runs/$A"
fi