#!/usr/bin/env bash
# Push the branch, open the pull request, and move the issue to
# `state/needs-human` — the three steps PROTOCOL.md requires, as one command.
#
# Why this exists:
#
#   `push-work` does the first third. GITEA-SETUP.md's own words are "the other
#   two thirds being manual is how they get skipped", and both loop briefs had
#   to carry a warning about it. A rule that depends on remembering three steps
#   is a rule that decays; this makes the sequence structural instead.
#
# It does NOT reimplement push-work's refusals — it CALLS push-work, so `main`,
# shared branches and force-push stay refused in exactly one place. Duplicating
# them would let the two copies drift, and the copy that drifts is the one that
# matters.
#
# PROTOCOL.md §Pull requests:
#   * branch `auto/<agent>/<issue#>-<topic>`, one item per branch
#   * open the PR with `Closes #<issue>` in the body
#   * label the issue `state/needs-human` and say, in one line, what to look at
#
#   propose-work -m "what to look at"            issue number from the branch
#   propose-work -i 12 -m "..." -t "title"       explicit
#   propose-work -m "..." --dry-run              print every call, make none
#
# The token is read from a file and passed to curl through a --config document
# on stdin. It is never an argument, never exported, never logged: arguments are
# world-readable in /proc, and this token can push.
set -euo pipefail

DRY=0; ISSUE=""; TITLE=""; LOOK=""
while [ $# -gt 0 ]; do
  case "$1" in
    -i|--issue) ISSUE="${2:-}"; shift 2 ;;
    -t|--title) TITLE="${2:-}"; shift 2 ;;
    -m|--look)  LOOK="${2:-}";  shift 2 ;;
    --dry-run)  DRY=1; shift ;;
    -h|--help)  sed -n '2,28p' "$0"; exit 0 ;;
    *) echo "propose-work: unknown argument '$1'" >&2; exit 1 ;;
  esac
done

here=$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)
repo_root=$(git rev-parse --show-toplevel) || exit 1
cd "$repo_root"
branch=$(git rev-parse --abbrev-ref HEAD)

# ── the issue number ────────────────────────────────────────────────────────
# PROTOCOL names the branch `auto/<agent>/<issue#>-<topic>`, so the number is
# already there. Deriving it means the PR cannot cite a different issue than the
# branch was cut for -- a mismatch nobody would notice in review.
if [ -z "$ISSUE" ]; then
  ISSUE=$(printf '%s\n' "$branch" | sed -n 's|^auto/[^/]*/\([0-9]\{1,\}\)-.*$|\1|p')
fi
if [ -z "$ISSUE" ]; then
  echo "propose-work: no issue number." >&2
  echo "  Either name the branch auto/<agent>/<issue#>-<topic>, or pass -i <n>." >&2
  exit 1
fi

# ── the "what to look at" line is NOT optional ──────────────────────────────
# PROTOCOL: an issue in `state/needs-human` "must say what to look at and what
# pass and fail look like, so a person can judge it in under a minute". An item
# that arrives without that sentence costs a human a round trip, so refuse here
# rather than let the label carry an empty promise.
if [ -z "$LOOK" ]; then
  echo "propose-work: -m is required." >&2
  echo "  state/needs-human means a person will look. Tell them what at, and" >&2
  echo "  what pass and fail look like, in one line." >&2
  exit 1
fi

# The FIRST commit on the branch, not the last: PROTOCOL is one item per
# branch, so the opening commit names the unit while HEAD may well be "fix
# typo". Falls back to HEAD when the branch has no unique commits.
[ -n "$TITLE" ] || TITLE=$(git log --format=%s --reverse "origin/main..HEAD" 2>/dev/null | head -1)
[ -n "$TITLE" ] || TITLE=$(git log --format=%s -1)

# ── credentials ─────────────────────────────────────────────────────────────
TOKFILE="${GITEA_TOKEN_FILE:-$HOME/.sylph-gitea-token}"
# Only when it will actually be used. `--dry-run` exists so an agent can check
# the command it is about to run; demanding a credential it never sends would
# make the check unavailable exactly where it is cheapest.
if [ "$DRY" = 0 ] && [ ! -s "$TOKFILE" ]; then
  echo "propose-work: no Gitea token at $TOKFILE" >&2
  echo "  The host must start the container with SYLPH_GITEA_TOKEN set." >&2
  exit 1
fi

remote=$(git remote get-url origin)
slug=$(printf '%s\n' "$remote" | sed -E 's|^.*://[^/]*/||; s|\.git$||')
API="https://$(printf '%s\n' "$remote" | sed -E 's|^.*://([^/@]*@)?([^/]*)/.*$|\2|')/api/v1"

# curl with the credential supplied out-of-band. `--config -` reads a document
# from stdin; the token never reaches argv or the environment.
api() { # api <METHOD> <PATH> [JSON]
  local method="$1" path="$2" data="${3:-}"
  { printf 'header = "Authorization: token %s"\n' "$(cat "$TOKFILE")"
    printf 'header = "Content-Type: application/json"\n'
    printf 'silent\nshow-error\nfail-with-body\nrequest = "%s"\n' "$method"
    [ -n "$data" ] && printf 'data = %s\n' "$(printf '%s' "$data" | python3 -c 'import json,sys; print(json.dumps(sys.stdin.read()))')"
    printf 'url = "%s%s"\n' "$API" "$path"
  } | curl --config -
}

echo "propose-work: branch=$branch issue=#$ISSUE repo=$slug"

if [ "$DRY" = 1 ]; then
  echo "  would: push-work"
  echo "  would: POST /repos/$slug/pulls   head=$branch base=main"
  echo "         title: $TITLE"
  echo "         body:  Closes #$ISSUE  +  $LOOK"
  echo "  would: PATCH labels on #$ISSUE -> state/needs-human (dropping other state/*)"
  echo "  would: POST /repos/$slug/issues/$ISSUE/comments  (the look-at line)"
  echo "propose-work: --dry-run, nothing sent"
  exit 0
fi

# ── 1. push (refusals live in push-work, not here) ──────────────────────────
"$here/push-work"

# ── 2. the pull request ─────────────────────────────────────────────────────
body=$(printf '%s\n\nCloses #%s\n\n**What to look at:** %s\n' "$TITLE" "$ISSUE" "$LOOK")
payload=$(python3 - "$TITLE" "$branch" "$body" <<'PY'
import json,sys
print(json.dumps({"title":sys.argv[1],"head":sys.argv[2],"base":"main","body":sys.argv[3]}))
PY
)
if out=$(api POST "/repos/$slug/pulls" "$payload" 2>&1); then
  num=$(printf '%s' "$out" | python3 -c 'import json,sys; print(json.load(sys.stdin)["number"])' 2>/dev/null || echo "?")
  echo "propose-work: opened PR #$num"
else
  # A second run after a fixup should not fail; the branch already has a PR.
  case "$out" in
    *"already exists"*) echo "propose-work: a pull request for $branch already exists — continuing" ;;
    *) echo "propose-work: opening the PR failed:" >&2; echo "$out" >&2; exit 1 ;;
  esac
fi

# ── 3. move the issue to state/needs-human ──────────────────────────────────
# "Move", not "add": leaving state/in-progress on it makes the board lie about
# what is waiting on a person.
labels=$(api GET "/repos/$slug/labels?limit=100")
want=$(printf '%s' "$labels" | python3 -c 'import json,sys; print([l["id"] for l in json.load(sys.stdin) if l["name"]=="state/needs-human"][0])')
cur=$(api GET "/repos/$slug/issues/$ISSUE/labels")
drop=$(printf '%s' "$cur" | python3 -c '
import json,sys
print(" ".join(str(l["id"]) for l in json.load(sys.stdin)
                if l["name"].startswith("state/") and l["name"]!="state/needs-human"))')
for id in $drop; do api DELETE "/repos/$slug/issues/$ISSUE/labels/$id" >/dev/null; done
api POST "/repos/$slug/issues/$ISSUE/labels" "{\"labels\":[$want]}" >/dev/null
echo "propose-work: #$ISSUE -> state/needs-human"

# ── 4. say what to look at, on the issue itself ─────────────────────────────
# The PR body has it too, but a person triaging the board reads issues.
cbody=$(python3 - "$LOOK" "$branch" <<'PY'
import json,sys
print(json.dumps({"body":"**Ready for a look.** %s\n\nBranch `%s`." % (sys.argv[1], sys.argv[2])}))
PY
)
api POST "/repos/$slug/issues/$ISSUE/comments" "$cbody" >/dev/null
echo "propose-work: done"