#!/usr/bin/env bash
#
# Bulk-link IMAP/SMTP accounts in Nextcloud Mail via `occ mail:account:create`.
#
# Usage:
#   OCC_CMD="docker exec -u www-data nc-dev php occ" ./mail-bulk-link.sh accounts.csv
#   OCC_CMD="sudo -u www-data php /var/www/nextcloud/occ" ./mail-bulk-link.sh accounts.csv
#
# CSV format (header required, exact column names):
#   userId,name,email,imapHost,imapPort,imapSsl,imapUser,imapPass,smtpHost,smtpPort,smtpSsl,smtpUser,smtpPass[,authMethod]
#
# - imapSsl/smtpSsl: ssl | tls | none
# - authMethod: optional, defaults to "password" (use "xoauth2" for OAuth)
# - Lines starting with # and empty lines are skipped.
# - Quote fields containing commas with double quotes per RFC 4180.
# - Passwords with shell-special chars are safe — they're passed as argv, not eval'd.

set -euo pipefail

OCC_CMD="${OCC_CMD:-}"
if [[ -z "$OCC_CMD" ]]; then
    echo "ERROR: Set OCC_CMD env var, e.g.:" >&2
    echo "  OCC_CMD=\"docker exec -u www-data nc-dev php occ\" $0 accounts.csv" >&2
    exit 2
fi

if [[ $# -ne 1 ]]; then
    echo "Usage: OCC_CMD=\"...\" $0 <accounts.csv>" >&2
    exit 2
fi

CSV="$1"
if [[ ! -r "$CSV" ]]; then
    echo "ERROR: cannot read $CSV" >&2
    exit 2
fi

# Read header and build column index map
IFS=, read -r -a HEADER < "$CSV"
declare -A COL
for i in "${!HEADER[@]}"; do
    name="${HEADER[$i]//$'\r'/}"   # strip CR if file is CRLF
    name="${name// /}"
    COL["$name"]=$i
done

required=(userId name email imapHost imapPort imapSsl imapUser imapPass smtpHost smtpPort smtpSsl smtpUser smtpPass)
for col in "${required[@]}"; do
    if [[ -z "${COL[$col]:-}" && "${COL[$col]:-x}" != "0" ]]; then
        echo "ERROR: missing required CSV column '$col'" >&2
        exit 2
    fi
done

# Minimal RFC-4180 parser: handles quoted fields and embedded commas.
# Outputs one field per line on FD 3; caller reads with mapfile.
parse_csv_line() {
    local line="$1"
    python3 -c '
import csv, sys
for row in csv.reader([sys.argv[1]]):
    for f in row:
        print(f)
' "$line"
}

ok=0
fail=0
skipped=0
lineno=1   # header already consumed

# Read remaining lines
tail -n +2 "$CSV" | while IFS= read -r line || [[ -n "$line" ]]; do
    lineno=$((lineno + 1))
    # Skip empty / comment lines
    [[ -z "${line//[[:space:]]/}" ]] && continue
    [[ "${line:0:1}" == "#" ]] && continue

    mapfile -t fields < <(parse_csv_line "$line")

    get() { echo "${fields[${COL[$1]}]:-}"; }

    userId=$(get userId)
    name=$(get name)
    email=$(get email)
    imapHost=$(get imapHost); imapPort=$(get imapPort); imapSsl=$(get imapSsl)
    imapUser=$(get imapUser); imapPass=$(get imapPass)
    smtpHost=$(get smtpHost); smtpPort=$(get smtpPort); smtpSsl=$(get smtpSsl)
    smtpUser=$(get smtpUser); smtpPass=$(get smtpPass)
    authMethod=""
    if [[ -n "${COL[authMethod]:-}" ]]; then
        authMethod=$(get authMethod)
    fi
    authMethod="${authMethod:-password}"

    # Basic sanity check
    for v in userId name email imapHost imapPort imapSsl imapUser imapPass smtpHost smtpPort smtpSsl smtpUser smtpPass; do
        if [[ -z "${!v}" ]]; then
            echo "[line $lineno] SKIP: empty field '$v'" >&2
            skipped=$((skipped + 1))
            continue 2
        fi
    done

    echo "[line $lineno] linking $email -> user '$userId' ..."

    # shellcheck disable=SC2086
    if $OCC_CMD mail:account:create \
        "$userId" "$name" "$email" \
        "$imapHost" "$imapPort" "$imapSsl" "$imapUser" "$imapPass" \
        "$smtpHost" "$smtpPort" "$smtpSsl" "$smtpUser" "$smtpPass" \
        "$authMethod"; then
        ok=$((ok + 1))
    else
        echo "[line $lineno] FAILED for user '$userId' ($email)" >&2
        fail=$((fail + 1))
    fi
done

echo "---"
echo "Done. ok=$ok fail=$fail skipped=$skipped"