#!/usr/bin/env bash
# Manually record an incoming Lightning payment to credit a lndhub.go user account.
#
# Mirrors the canonical incoming-settlement path in lib/service/invoicesubscription.go
# (ProcessInvoiceUpdate): inserts a settled `invoices` row plus a `transaction_entries`
# row crediting the user's `current` account and debiting their `incoming` account
# (which is exempt from the non-negative check_balance() trigger, so it may go negative).
#
# Usage:
#   ./gitno/credit-account.sh --env-file <path/to/.env> \
#       --login <login> --sats <N> [--memo "manual credit"]
#
# The --env-file is the lndhub.go .env file (the same one loaded by godotenv in
# cmd/server/main.go). Only DATABASE_URI is read from it; the value from the file
# ALWAYS takes precedence over any DATABASE_URI already present in the environment.
#
# Requires: psql. The whole operation runs in one transaction; ON_ERROR_STOP=1
# aborts on any error so the tx is rolled back and psql exits non-zero.

set -euo pipefail

usage() {
    cat <<'EOF'
Usage: credit-account.sh --env-file <path/to/.env> --login <login> --sats <N> [--memo "..."]

Options:
  --env-file  Path to the lndhub.go .env file (required). Only DATABASE_URI is
              read from it; the file value always wins over the environment.
  --login     User login (required)
  --sats      Amount in satoshis to credit (required, positive integer)
  --memo      Memo for the recorded invoice (default: "manual credit")
  -h, --help
EOF
    exit "${1:-0}"
}

env_file=""
login=""
sats=""
memo="manual credit"

while [[ $# -gt 0 ]]; do
    case "$1" in
        --env-file) env_file="$2"; shift 2 ;;
        --login)    login="$2";    shift 2 ;;
        --sats)     sats="$2";     shift 2 ;;
        --memo)     memo="$2";     shift 2 ;;
        -h|--help)  usage 0 ;;
        *) echo "Unknown argument: $1" >&2; usage 1 ;;
    esac
done

[[ -n "$env_file" ]] || { echo "Error: --env-file is required" >&2; usage 1; }
[[ -n "$login" ]]    || { echo "Error: --login is required" >&2; usage 1; }
[[ -n "$sats"  ]]    || { echo "Error: --sats is required"  >&2; usage 1; }
[[ "$sats" =~ ^[1-9][0-9]*$ ]] || { echo "Error: --sats must be a positive integer" >&2; usage 1; }

# Sanity-check psql is available.
command -v psql >/dev/null || { echo "Error: psql not found in PATH" >&2; exit 1; }

# Extract a single KEY=VALUE entry from a .env file, matching godotenv semantics:
#   - skips blank lines and lines whose first non-whitespace char is '#'
#   - tolerates an optional leading 'export '
#   - case-insensitive key match
#   - strips one pair of surrounding matching quotes (" or ') from the value
# Writes the result to stdout; empty output means "not found".
extract_env_key() {
    local file="$1" key="$2" line k v
    while IFS= read -r line || [[ -n "$line" ]]; do
        # Trim leading whitespace; skip blanks and comments
        line="${line#"${line%%[![:space:]]*}"}"
        [[ -z "$line" || "${line:0:1}" == "#" ]] && continue
        # Strip optional 'export ' prefix
        [[ "$line" == export\ * ]] && line="${line#export }"
        # Split on the first '='
        [[ "$line" != *=* ]] && continue
        k="${line%%=*}"
        v="${line#*=}"
        # Case-insensitive key compare
        if [[ "${k,,}" == "${key,,}" ]]; then
            # Strip one pair of surrounding matching single or double quotes
            if [[ ${#v} -ge 2 ]]; then
                if [[ "${v:0:1}" == '"' && "${v: -1}" == '"' ]]; then v="${v:1:-1}";
                elif [[ "${v:0:1}" == "'" && "${v: -1}" == "'" ]]; then v="${v:1:-1}"; fi
            fi
            printf '%s\n' "$v"
            return 0
        fi
    done < "$file"
    return 1
}

[[ -r "$env_file" ]] || { echo "Error: --env-file not readable: $env_file" >&2; exit 1; }

# DATABASE_URI is sourced exclusively from --env-file; the file value always wins
# over any DATABASE_URI already present in the environment.
if ! DATABASE_URI="$(extract_env_key "$env_file" DATABASE_URI)"; then
    echo "Error: DATABASE_URI not found in $env_file" >&2
    exit 1
fi
[[ -n "$DATABASE_URI" ]] || { echo "Error: DATABASE_URI is empty in $env_file" >&2; exit 1; }

case "$DATABASE_URI" in
    postgres://*|postgresql://*) ;;
    *) echo "Error: DATABASE_URI must start with postgres:// or postgresql:// (got: $DATABASE_URI)" >&2; exit 1 ;;
esac

psql "$DATABASE_URI" \
    -v ON_ERROR_STOP=1 \
    -v login="$login" \
    -v sats="$sats" \
    -v memo="$memo" \
    <<'SQL'
\set ON_ERROR_STOP on
\echo Resolving user, accounts, and recording the credit in one transaction...

-- Pass the CLI args into server-side GUCs so the DO block (dollar-quoted, where
-- psql :var substitution does NOT happen) can read them via current_setting().
-- These SETs run outside any dollar-quote, so :'login'/:sats/:'memo' are substituted
-- by psql as a properly-quoted SQL literal / bare token here.
SET app.lndhub_login = :'login';
SET app.lndhub_sats  = :sats;
SET app.lndhub_memo  = :'memo';

BEGIN;

-- Look up user + accounts, validate, and insert the invoice + ledger entry.
-- Raises an exception (aborting the tx, psql exits non-zero via ON_ERROR_STOP)
-- with a helpful message if the user or either account is missing.
DO $$
DECLARE
    v_uid      bigint;
    v_curr     bigint;
    v_inc      bigint;
    v_inv_id   bigint;
    v_login    text := current_setting('app.lndhub_login');
    v_sats     bigint := current_setting('app.lndhub_sats')::bigint;
    v_memo     text := current_setting('app.lndhub_memo');
BEGIN
    SELECT id INTO v_uid FROM users WHERE login = v_login;
    IF NOT FOUND THEN
        RAISE EXCEPTION 'no user found with login = %', v_login;
    END IF;

    SELECT id INTO v_curr FROM accounts WHERE user_id = v_uid AND type = 'current';
    IF NOT FOUND THEN
        RAISE EXCEPTION 'user % has no current account', v_uid;
    END IF;

    SELECT id INTO v_inc FROM accounts WHERE user_id = v_uid AND type = 'incoming';
    IF NOT FOUND THEN
        RAISE EXCEPTION 'user % has no incoming account', v_uid;
    END IF;

    RAISE NOTICE 'user_id=%  current_acct=%  incoming_acct=%  amount=% sats',
        v_uid, v_curr, v_inc, v_sats;

    -- Settled incoming invoice. Constraints honored:
    --   * destination_pubkey_hex NOT NULL -> 66-hex dummy
    --   * settled => preimage NOT NULL (check_primage_exists)
    --   * fresh r_hash/preimage per run keeps rows distinct
    --   * uses gen_random_uuid() (built-in core since PG13, no pgcrypto needed);
    --     32 hex chars is sufficient for a dummy identifier
    INSERT INTO invoices
        (type, user_id, amount, memo, destination_pubkey_hex, r_hash, preimage,
         state, settled_at, created_at, internal)
    VALUES
        ('incoming', v_uid, v_sats, v_memo,
         '000000000000000000000000000000000000000000000000000000000000000000',
         replace(gen_random_uuid()::text, '-', ''),
         replace(gen_random_uuid()::text, '-', ''),
         'settled', now(), now(), false)
    RETURNING id INTO v_inv_id;

    RAISE NOTICE 'invoice_id=%', v_inv_id;

    -- Ledger entry: credit current (+amount), debit incoming (-amount).
    --   * debit_account_id != credit_account_id (current != incoming) -> check_not_same_account ok
    --   * debit on `incoming` is exempt from check_balance() -> may go negative
    --   * fresh invoice_id keeps unique_tx_entry_tuple satisfied
    INSERT INTO transaction_entries
        (user_id, invoice_id, credit_account_id, debit_account_id, amount, entry_type, created_at)
    VALUES
        (v_uid, v_inv_id, v_curr, v_inc, v_sats, 'incoming', now());

    RAISE NOTICE 'credited % sats to user % (login=%)', v_sats, v_uid, v_login;
END $$;

COMMIT;

-- Resulting current-account balance (same query as CurrentUserBalance in
-- lib/service/user.go: sum over account_ledgers for the user's current account).
SELECT
    (SELECT sum(al.amount)
       FROM account_ledgers al
       JOIN accounts a ON a.id = al.account_id
      WHERE a.user_id = (SELECT id FROM users WHERE login = current_setting('app.lndhub_login'))
        AND a.type = 'current') AS new_balance_sat;
SQL