#!/usr/bin/env bash
# send-invitations.sh — batch-insert beta invitations from a validated
# cohort CSV, generate unique invite codes, render personalised email
# bodies, optionally dispatch via SMTP.
#
# Wraps the validate-cohort.sh sanity check + a transactional INSERT
# into beta_invites + a per-recipient email render. Splits "generate
# the codes + render the emails" from "actually send" so a dry-run
# produces a flat directory of `.eml` files the operator can review
# before dispatch.
#
# v1.0.10 Cluster 3.4.
#
# Usage :
#   # Step 1 : dry-run (default). Inserts beta_invites rows, emits
#   # eml files but does NOT send anything.
#   DATABASE_URL=postgres://... \
#     bash scripts/soft-launch/send-invitations.sh path/to/cohort.csv
#
#   # Step 2 : after reviewing the eml files, dispatch with msmtp /
#   # sendmail / aws-ses-cli (or whatever SEND_CMD points at).
#   SEND=1 SEND_CMD='msmtp -t' \
#     bash scripts/soft-launch/send-invitations.sh path/to/cohort.csv
#
# Required env :
#   DATABASE_URL    Postgres URL (read+write to beta_invites)
#   FRONTEND_URL    base URL the invite link points at
#                   (e.g. https://staging.veza.fr)
#
# Optional env :
#   SEND=1          actually dispatch ; otherwise dry-run (eml only)
#   SEND_CMD        sendmail-compatible command (default: 'msmtp -t')
#   SENT_BY_EMAIL   operator email for the beta_invites.sent_by FK ;
#                   defaults to the value in the CSV's third column
#   FROM_ADDR       From: header (default: invitations@veza.fr)
#   SUBJECT         email subject (default: 'You're in for the Veza beta')
#   TEMPLATE        path to eml template (default:
#                   templates/email/beta_invite.html.template)
#   FORCE=1         skip validate-cohort.sh failures (use with care)
#
# Exit codes :
#   0  — everything succeeded
#   1  — cohort validation failed (see validate-cohort.sh)
#   2  — DB transaction failed
#   3  — required env missing
#   4  — dispatch failed for at least one recipient (see logs)
set -euo pipefail

REPO_ROOT="$(cd "$(dirname "$0")/.." && pwd)"

CSV=${1:-}
if [ -z "$CSV" ] || [ ! -f "$CSV" ]; then
  echo "usage: bash scripts/soft-launch/send-invitations.sh path/to/cohort.csv" >&2
  exit 3
fi

DATABASE_URL=${DATABASE_URL:-?}
FRONTEND_URL=${FRONTEND_URL:-?}
[ "$DATABASE_URL" = "?" ] && { echo "DATABASE_URL required" >&2; exit 3; }
[ "$FRONTEND_URL" = "?" ] && { echo "FRONTEND_URL required" >&2; exit 3; }

SEND=${SEND:-0}
SEND_CMD=${SEND_CMD:-msmtp -t}
FROM_ADDR=${FROM_ADDR:-invitations@veza.fr}
SUBJECT=${SUBJECT:-Vous êtes admis dans la bêta Veza}
TEMPLATE=${TEMPLATE:-$REPO_ROOT/templates/email/beta_invite.eml.template}
FORCE=${FORCE:-0}
SESSION_DATE="$(date +%Y%m%d-%H%M)"
OUTDIR="$REPO_ROOT/scripts/soft-launch/out-${SESSION_DATE}"

command -v psql    >/dev/null 2>&1 || { echo "psql required" >&2; exit 3; }
command -v openssl >/dev/null 2>&1 || { echo "openssl required" >&2; exit 3; }

# Step 1 — validate the cohort. Bypass with FORCE=1 if needed.
echo "→ validating cohort $CSV"
if ! bash "$(dirname "$0")/validate-cohort.sh" "$CSV"; then
  if [ "$FORCE" != "1" ]; then
    echo "ERROR: cohort validation failed. Re-run with FORCE=1 to bypass (not recommended)." >&2
    exit 1
  fi
  echo "WARN : cohort validation reported issues but FORCE=1 set — proceeding."
fi

mkdir -p "$OUTDIR"
echo "→ output dir $OUTDIR"

# Step 2 — generate codes + insert rows + render emails. Each insert
# is one transaction so a partial failure leaves consistent state.
gen_code() {
  # 16-char base32-ish (no 0/1/I/L) so codes are paste-friendly.
  openssl rand -hex 16 | tr 'a-f0-9' 'a-z2-9' \
    | tr -d 'oilOIL01' | head -c 16
}

if [ ! -f "$TEMPLATE" ]; then
  echo "ERROR: template $TEMPLATE not found." >&2
  exit 3
fi

inserted=0
failed=0
failed_emails=()

while IFS=, read -r email cohort sent_by_email; do
  email=$(echo "$email" | tr -d '\r' | xargs)
  cohort=$(echo "$cohort" | tr -d '\r' | xargs)
  sent_by_email=$(echo "$sent_by_email" | tr -d '\r' | xargs)

  code=$(gen_code)

  # Resolve sent_by user_id (may be NULL if operator email isn't a
  # registered user — e.g. ops shared mailbox).
  sent_by_id=$(psql "$DATABASE_URL" -A -t -c "
    SELECT id::text FROM users WHERE email = '$sent_by_email' LIMIT 1;
  " 2>/dev/null | tr -d ' ' || echo "")

  if [ -z "$sent_by_id" ]; then
    sent_by_clause="NULL"
  else
    sent_by_clause="'$sent_by_id'"
  fi

  if ! psql "$DATABASE_URL" -1 -c "
    INSERT INTO beta_invites (code, email, cohort, sent_by, expires_at)
    VALUES ('$code', '$email', '$cohort', $sent_by_clause, NOW() + INTERVAL '30 days');
  " >/dev/null 2>&1; then
    failed=$(( failed + 1 ))
    failed_emails+=("$email")
    continue
  fi
  inserted=$(( inserted + 1 ))

  # Render the eml — operator-readable, ready for SEND_CMD.
  eml="$OUTDIR/${email//[^a-zA-Z0-9._-]/_}.eml"
  invite_url="$FRONTEND_URL/signup?invite=$code"
  sed \
    -e "s|{{TO_ADDR}}|$email|g" \
    -e "s|{{FROM_ADDR}}|$FROM_ADDR|g" \
    -e "s|{{SUBJECT}}|$SUBJECT|g" \
    -e "s|{{INVITE_URL}}|$invite_url|g" \
    -e "s|{{INVITE_CODE}}|$code|g" \
    -e "s|{{COHORT}}|$cohort|g" \
    -e "s|{{FRONTEND_URL}}|$FRONTEND_URL|g" \
    "$TEMPLATE" > "$eml"
done < <(tail -n +2 "$CSV")

echo "→ inserted $inserted invitations into beta_invites"
echo "→ rendered $inserted emails to $OUTDIR"
[ "$failed" -gt 0 ] && {
  echo "WARN : $failed insert(s) failed — see logs above"
  for e in "${failed_emails[@]}"; do echo "  - $e"; done
}

# Step 3 — optionally dispatch.
if [ "$SEND" != "1" ]; then
  echo ""
  echo "DRY-RUN — review the eml files in $OUTDIR before sending."
  echo "When ready :"
  echo "  SEND=1 SEND_CMD='$SEND_CMD' bash scripts/soft-launch/send-invitations.sh $CSV"
  exit 0
fi

echo "→ dispatching via : $SEND_CMD"
dispatch_failed=0
for eml in "$OUTDIR"/*.eml; do
  if ! $SEND_CMD < "$eml" >>"$OUTDIR/dispatch.log" 2>&1; then
    dispatch_failed=$(( dispatch_failed + 1 ))
    echo "  FAIL : $eml" | tee -a "$OUTDIR/dispatch.log"
  fi
done

echo ""
if [ "$dispatch_failed" -gt 0 ]; then
  echo "WARN : $dispatch_failed dispatch(es) failed — see $OUTDIR/dispatch.log"
  exit 4
fi
echo "PASS : all $inserted invitations dispatched."
echo "Track redemption with :"
echo "  psql \"\$DATABASE_URL\" -c 'SELECT cohort, count(*) FILTER (WHERE used_at IS NOT NULL) AS redeemed, count(*) AS total FROM beta_invites GROUP BY cohort ORDER BY cohort;'"