#!/usr/bin/env bash
# Route agent + prepare branch.
# Reads the event context from env (set by the calling step), writes the agent registry to
# /tmp/agents.json, picks which agent to run, emits step outputs (name/model/vision/mode/branch/new)
# to $GITHUB_OUTPUT, configures git identity, and prepares/publishes the working branch.
#
# Required env (all provided by the workflow step): BODY IBODY CID IS_PR NUM GT
#   TOKEN_PM TOKEN_SENIOR TOKEN_JUNIOR TOKEN_LEAD TOKEN_QA
#   GITHUB_SERVER_URL GITHUB_REPOSITORY GITHUB_OUTPUT
set -eu

# --- agent registry: model + capabilities + mode + role + skills ---
# The registry is the SINGLE SOURCE OF TRUTH, kept in agents.json next to this
# script. install-opencode.sh derives its ollama-cloud provider `models:` map
# from the same file, so an agent's model can never be missing from the provider
# config — drift is impossible by construction. See issue #31.
# `skills` is the allow-list of opencode Skills each agent may load. It scopes the
# `permission.skill` block written into opencode.json (see install-opencode.sh) so an agent only
# ever sees (and can load) the skills relevant to its role. Skills NOT listed here are hidden from
# that agent entirely — not even the one-line summary appears in its <available_skills>, so the
# full API/how-to detail never reaches an agent that shouldn't act on it. A teammate can still learn
# *that* another agent has a capability from the roster and ask them to use it.
AGENTS_JSON="${SCRIPTS:-$(dirname -- "$0")}/agents.json"
cp "$AGENTS_JSON" /tmp/agents.json
# On a new issue, @pm auto-assesses. On a comment, route by the @mention.
# A comment event has a comment id (CID); an issue-opened event does not. (event_name is unreliable
# here — see agent.yml: this reusable workflow sees it as 'workflow_call'.)
if [ -n "$CID" ]; then scan="$BODY"; else scan="$IBODY"; fi
name=""
for a in pm junior senior lead qa; do
  case "$scan" in *"@$a"*) name=$a; break;; esac
done
if [ -z "$name" ]; then
  if [ -z "$CID" ]; then name=pm; else echo "no known agent mentioned"; exit 1; fi
fi
model=$(jq -r --arg a "$name" '.[$a].model'  /tmp/agents.json)
vision=$(jq -r --arg a "$name" '.[$a].vision' /tmp/agents.json)
mode=$(jq -r --arg a "$name" '.[$a].mode'   /tmp/agents.json)
# Compact JSON array of the skills this agent may load (scopes permission.skill in install-opencode.sh).
skills=$(jq -c --arg a "$name" '.[$a].skills // []' /tmp/agents.json)
echo "Routing to @$name (model=$model vision=$vision mode=$mode skills=$skills)"
{ echo "name=$name"; echo "model=$model"; echo "vision=$vision"; echo "mode=$mode"; echo "skills=$skills"; } >> "$GITHUB_OUTPUT"

# Act as the agent's own Gitea user when its token is set; else the built-in bot.
case "$name" in
  pm) TOK="$TOKEN_PM";; senior) TOK="$TOKEN_SENIOR";; junior) TOK="$TOKEN_JUNIOR";;
  lead) TOK="$TOKEN_LEAD";; qa) TOK="$TOKEN_QA";; *) TOK="";;
esac
[ -z "$TOK" ] && TOK="$GT"
git config user.name "$name"
git config user.email "$name@ffaerber.duckdns.org"
API="${GITHUB_SERVER_URL}/api/v1/repos/${GITHUB_REPOSITORY}"
hdr=(-H "Authorization: token $TOK" -H "Content-Type: application/json")
if [ -n "$IS_PR" ]; then                     # comment on a PR -> resume its branch
  ref=$(curl -s -H "Authorization: token $GT" "$API/pulls/$NUM" | jq -r .head.ref)
  git fetch origin "$ref" && git checkout "$ref"
  { echo "branch=$ref"; echo "new=false"; } >> "$GITHUB_OUTPUT"
elif git ls-remote --exit-code --heads origin "ai/issue-$NUM" >/dev/null 2>&1; then
  # comment on an issue whose branch ALREADY exists (a prior run / open PR) -> RESUME it, so new
  # commits fast-forward onto the same branch and update its PR. Branching fresh from main here would
  # be rejected on push as non-fast-forward and the new work would be silently lost (see issue #17).
  git fetch origin "ai/issue-$NUM" && git checkout "ai/issue-$NUM"
  { echo "branch=ai/issue-$NUM"; echo "new=false"; } >> "$GITHUB_OUTPUT"
else                                         # comment on an issue, no branch yet -> new branch
  git checkout -b "ai/issue-$NUM"
  { echo "branch=ai/issue-$NUM"; echo "new=true"; } >> "$GITHUB_OUTPUT"
  # For dev agents, publish the branch immediately and tell the maintainer where to watch.
  if [ "$mode" = "pr" ]; then
    git push -u origin "HEAD:ai/issue-$NUM" || true
    url="${GITHUB_SERVER_URL}/${GITHUB_REPOSITORY}/src/branch/ai/issue-$NUM"
    curl -sS -X POST "${hdr[@]}" "$API/issues/$NUM/comments" \
      -d "$(jq -nc --arg b "🔨 **@$name** is on it — building on branch [\`ai/issue-$NUM\`]($url). I'll open a PR when it's ready." '{body:$b}')" >/dev/null || true
  fi
fi