#!/usr/bin/env bash
# ---------------------------------------------------------------------------
# Compare tracked configuration against the live installation.
#
# Run this before every deploy, and after every migration, to prove that the
# repository and the host agree.
#
# Usage:
#   scripts/pi-diff.sh                # runtime + every scenario
#   scripts/pi-diff.sh runtime
#   scripts/pi-diff.sh <scenario>
#
# Exit status: 0 when everything matches, 1 when anything differs.
# ---------------------------------------------------------------------------
# shellcheck source=lib/common.sh
. "$(dirname "${BASH_SOURCE[0]}")/lib/common.sh"

DIFFS=0

diff_runtime() {
  head1 "runtime  (~/.pi/agent)"
  local live="$HOME/.pi/agent"
  local tracked="$REPO_ROOT/runtime/agent"

  diff_file "$tracked/settings.json" "$live/settings.json" "settings.json" || DIFFS=$((DIFFS + 1))

  # models.json is rendered from a template, so compare the redacted forms.
  if [ -f "$live/models.json" ]; then
    local a b
    a="$(mktemp)"; b="$(mktemp)"
    python3 - "$tracked/models.json.template" >"$a" <<'PY'
import json, re, sys
print(re.sub(r'"apiKey":\s*".*?"', '"apiKey": "<X>"',
             json.dumps(json.load(open(sys.argv[1])), ensure_ascii=False, indent=2, sort_keys=True)))
PY
    python3 - "$live/models.json" >"$b" <<'PY'
import json, re, sys
print(re.sub(r'"apiKey":\s*".*?"', '"apiKey": "<X>"',
             json.dumps(json.load(open(sys.argv[1])), ensure_ascii=False, indent=2, sort_keys=True)))
PY
    if cmp -s "$a" "$b"; then
      ok "models.json (key-redacted comparison)"
    else
      printf '%s  models.json (key-redacted comparison)\n' "${C_YELLOW}DIFF${C_OFF}"
      diff -u --label repo/models.json.template "$a" --label live/models.json "$b" | sed 's/^/      /'
      DIFFS=$((DIFFS + 1))
    fi
    rm -f "$a" "$b"
  else
    warn "live ~/.pi/agent/models.json is absent"
    DIFFS=$((DIFFS + 1))
  fi

  local rel
  while IFS= read -r rel; do
    diff_file "$tracked/$rel" "$live/$rel" "$rel" || DIFFS=$((DIFFS + 1))
  done < <(cd "$tracked" && find extensions prompts -type f 2>/dev/null | sort)
}

diff_scenario() {
  local name="$1" dir
  dir="$(require_scenario "$name")"
  local profile="$dir/profile.toml"
  [ -f "$profile" ] || die "scenario '$name' has no profile.toml"

  local workspace
  workspace="$(toml_get "$profile" scenario workspace)"
  [ -n "$workspace" ] || die "scenario '$name': [scenario].workspace is not set"

  head1 "$name  ($workspace)"

  if [ ! -d "$dir/workspace" ]; then
    warn "no tracked workspace/ for '$name'; nothing to compare"
    return
  fi
  if [ ! -d "$workspace" ]; then
    warn "live workspace $workspace does not exist yet"
    DIFFS=$((DIFFS + 1))
    return
  fi

  local rel
  while IFS= read -r rel; do
    diff_file "$dir/workspace/$rel" "$workspace/$rel" "$rel" || DIFFS=$((DIFFS + 1))
  done < <(cd "$dir/workspace" && find . -type f -printf '%P\n' | sort)

  # Report live files that the repository does not track, so drift is visible in
  # both directions. Runtime state and toolchains are expected and are skipped.
  local untracked=()
  while IFS= read -r rel; do
    case "$rel" in
      .ccgram-uploads/*|*/__pycache__/*|*/.venv/*|.venv/*|*.pyc|*.bak-*|\
      telegram-gateway/*|download.html|.pi/launch.json|*.log) continue ;;
    esac
    # Vendored shared modules are installed by deploy-scenario.sh and are not in
    # the scenario's workspace/, so compare them against shared/extensions/
    # instead of reporting them as untracked -- otherwise the one file most
    # likely to drift is the one the diff stays silent about.
    case "$rel" in
      .pi/extensions/_shared/*)
        mod="${rel#.pi/extensions/_shared/}"
        src="$REPO_ROOT/shared/extensions/$mod"
        if [ ! -f "$src" ]; then
          untracked+=("$rel (no longer in shared/extensions)")
        elif ! diff_file "$src" "$workspace/$rel" "$rel (vendored from shared/extensions)"; then
          DIFFS=$((DIFFS + 1))
        fi
        continue
        ;;
    esac
    [ -f "$dir/workspace/$rel" ] || untracked+=("$rel")
  done < <(cd "$workspace" && find . -type f -printf '%P\n' | sort)

  if [ "${#untracked[@]}" -gt 0 ]; then
    printf '%sUNTRACKED in live workspace:%s\n' "$C_DIM" "$C_OFF"
    printf '      %s\n' "${untracked[@]}"
  fi
}

TARGET="${1:-}"
if [ -z "$TARGET" ]; then
  diff_runtime
  while IFS= read -r s; do diff_scenario "$s"; done < <(list_scenarios)
elif [ "$TARGET" = "runtime" ]; then
  diff_runtime
else
  diff_scenario "$TARGET"
fi

printf '\n'
if [ "$DIFFS" -eq 0 ]; then
  ok "repository and live installation agree"
else
  warn "$DIFFS difference(s) found"
fi
exit $((DIFFS > 0))