#!/usr/bin/env bash
# Scribe — record that this session OPENED a rule, not merely saw it named (#4100).
#
# WHAT THIS CLOSES
#
# The rule arms keep a ledger of every id they have NAMED, and the injected
# line used to tell the reader "You saw it earlier this session". That claim
# was never checked. The line those arms emit is a TEASER — title, trigger,
# `get_rule(N)` — so a session can be named a rule twenty times and never read
# one word of it, and after a compaction the teaser is summarised away leaving
# nothing at all. The server was asserting something about the reader's
# context that it had no way to know.
#
# This is the observable half. PostToolUse fires for MCP tools (the event's own
# output schema carries `updatedMCPToolOutput`, which would be meaningless
# otherwise), so the `get_rule` CALL can be watched directly.
#
# WHY THIS IS NOT THE SELF-REPORT MILESTONE 386 REJECTED
#
# 386 ruled out asking the session whether it holds a rule, because a model
# asked "do you still hold rule 156?" will say yes and the answer is
# unverifiable self-report. That objection is about ASKING. This asks nobody:
# a tool call happened or it did not, and the harness reports it either way.
# Recording what a session DID is a different kind of evidence from believing
# what it says about itself.
#
# WHAT IT DELIBERATELY DOES NOT DO
#
# It does not prove the rule is still in context — nothing can, and a
# compaction can drop it moments later. That is why `.opened.ids` ages exactly
# like `.rules.ids` and is cleared on the same events (#3749): both ledgers
# describe a context that no longer exists once the context is destroyed. The
# claim it supports is only ever "you opened this, pull it again if you no
# longer hold it", which stays true in every case and carries its own remedy.
#
# SINCE MILESTONE 458 STEP 7 it also reports the open, with the calls that
# came just before it, so the server can learn which moments a rule belongs
# on (below). Silent on outage, like every arm that fires per call.
#
# EXIT 0, ALWAYS. This decorates a ledger; a bookkeeping failure must never
# turn a successful tool call into a hook error. Worst case the id is missed
# and the reader is offered a rule it already read — the cost of a wrong guess
# here is one extra line, in the direction that shows more rather than less.
set -uo pipefail

# shellcheck source=plugin/hooks/scribe_defs.sh
. "$(dirname "${BASH_SOURCE[0]}")/scribe_defs.sh"

event=$(cat 2>/dev/null || true)
[ -n "$event" ] || exit 0

event_flat=$(printf '%s' "$event" | scribe_json_flat)
session_id=$(scribe_json_pick "$event_flat" '.session_id')
[ -n "$session_id" ] || exit 0

# The matcher in hooks.json already narrows to the get_rule tools, but the
# server segment of an MCP tool name varies with how the plugin was installed,
# so the id is read from whichever field is actually present rather than from
# an assumed tool name. An event that carries none simply records nothing.
rule_id=$(scribe_json_pick "$event_flat" '.tool_input.rule_id')
rule_id=$(printf '%s' "$rule_id" | tr -cd '0-9')
[ -n "$rule_id" ] || exit 0

# The same directory the naming ledger uses. One session keeps its state in one
# place, and the prior-art name is kept for the reason scribe_tool_rules.sh
# gives: renaming it would orphan every live session's state for a cosmetic
# gain.
state_dir="${TMPDIR:-/tmp}/scribe-priorart"
mkdir -p "$state_dir" 2>/dev/null || true
safe_sid=$(printf '%s' "$session_id" | tr -c 'A-Za-z0-9._-' '_')

# Stamped and append-only, exactly like the naming ledger — so the same reader
# (`scribe_rules_live`) ages both, and the last entry for an id wins.
printf '%s\n' "$rule_id" | scribe_rules_append "$state_dir/${safe_sid}.opened.ids"

# ── What came just before the open (milestone 458 step 7) ─────────────────
#
# scribe_moment.sh writes every call to `scribe-moment/<sid>.acts`. The ones
# from the last three minutes go to the server with this rule's id: a rule
# opened just after a moment fired is evidence it belongs on that moment, and
# once that repeats across sessions the server answers with one line asking
# the reader to offer the operator the mount. Nothing is mounted by this.
command -v curl >/dev/null 2>&1 || exit 0
scribe_config || exit 0
acts_file="${TMPDIR:-/tmp}/scribe-moment/${safe_sid}.acts"
[ -f "$acts_file" ] || exit 0
now=$(date +%s 2>/dev/null) || exit 0
acts=$(awk -F '\t' -v since=$((now - 180)) \
  '$1 + 0 >= since { sub(/^[^\t]*\t/, ""); print }' "$acts_file" 2>/dev/null \
  | tail -n 30 | paste -sd ',' - 2>/dev/null)
[ -n "$acts" ] || exit 0

sid_esc=$(printf '%s' "$session_id" | scribe_json_escape) || exit 0
event_cwd=$(scribe_json_pick "$event_flat" '.cwd')
scope=$(scribe_scope_query "${event_cwd:-${CLAUDE_PROJECT_DIR:-$PWD}}")
body=$(printf '{"rule_id":%s,"session_id":"%s","acts":[%s]}' "$rule_id" "$sid_esc" "$acts" \
  | curl -fsS --max-time 3 \
    -H "Authorization: Bearer ${token}" \
    -H "Content-Type: application/json" \
    --data-binary @- \
    "${url%/}/api/plugin/rule-opened${scope:+?$scope}" 2>/dev/null) || exit 0

context=$(scribe_json_pick "$(printf '%s' "$body" | scribe_json_flat)" '.context')
[ -n "$context" ] || exit 0
scribe_json_out PostToolUse "$context"
exit 0