#!/bin/bash

# Stoat user management.
#
# Deliberately the thinnest set of the four, because Stoat gives the least to
# work with. Its service containers are distroless (no shell), it has no admin
# CLI, and its admin HTTP surface is not a stable documented API — so the only
# durable handles are the public auth endpoint and the database itself.
#
# What that rules out, and why:
#
#   Role/permission editing — Stoat's permissions are per-server bitfields held
#   on server_members, not a global admin flag. There is no single "make admin"
#   to toggle; it is a server-by-server concept the app models properly and a
#   button would misrepresent. Confirmed against a running instance: the user
#   document holds only _id/username/discriminator, and GET /users/@me adds only
#   relationship and online. There is no privileged bit to set.
#
# Password reset WAS excluded for the same reason — Stoat hashes with argon2
# through its own authifier layer, and a hand-rolled hash that is subtly wrong
# writes an account nothing can verify, with no error at the time. That objection
# is answered not by reimplementing the hash but by refusing to: authifier's own
# password_reset field takes a token, and its reset endpoint does the hashing.
# See authAdapter_stoat_setPassword.

# Host-local API base for this app, e.g. http://127.0.0.1:8860/api.
#
# 127.0.0.1 rather than the published LAN address: this only ever runs on the
# box itself, and the loopback route does not depend on which interface the
# advertised URL happens to name.
_stoatApiLocal() {
    local app_name="${1:-stoat}"
    local compose="$containers_dir$app_name/docker-compose.yml"
    local ports external
    ports=$(tagsManagerGetTagContent "$compose" "PORTS_TAG_1" 2>/dev/null)
    external="${ports%%:*}"
    [[ -z "$external" || "$external" == PORTS_DATA* ]] && return 1
    printf 'http://127.0.0.1:%s/api' "$external"
}

# JSON-encode one value, so an apostrophe in a password cannot end the string.
_stoatJson() { printf '%s' "$1" | python3 -c 'import sys,json;print(json.dumps(sys.stdin.read()))'; }

# True when the instance already holds at least one account.
_stoatAccountExists() {
    local n
    n=$(_stoatMongo 'print(db.accounts.countDocuments({}))' | tr -dc '0-9')
    [[ -n "$n" && "$n" != "0" ]]
}

# Register an account and finish onboarding, which is what actually makes it a
# usable identity: `accounts` holds the login, `users` the handle, and Stoat
# creates the second only when onboarding completes. An account left un-onboarded
# can sign in and then sits on a "pick a username" screen forever, and — worse for
# a first account — has not yet taken instance ownership.
#
# Done over HTTP rather than by writing Mongo directly because passwords go
# through Stoat's own argon2 layer. Reimplementing that in bash means matching
# its parameters exactly, and a subtly wrong hash writes an account nothing can
# verify: no error at the time, just a login that never works.
_stoatCreateAccount() {
    local api="$1" email="$2" pass="$3" user="$4"
    local body out token

    body="{\"email\":$(_stoatJson "$email"),\"password\":$(_stoatJson "$pass")}"
    out=$(runFileOp curl -sS --max-time 20 -X POST "${api}/auth/account/create" \
            -H 'Content-Type: application/json' -d "$body" 2>&1)

    # On a closed instance the API answers MissingInvite. Rather than refuse, mint
    # one: an admin creating an account here IS the authorisation, and requiring
    # them to go and generate an invite by hand first would make CFG_STOAT_INVITE_ONLY
    # a switch that breaks LibrePortal's own tooling.
    #
    # Reactive rather than reading the config, so this follows the instance's ACTUAL
    # state — someone who edits Revolt.toml by hand, or flips it after install, gets
    # the same behaviour without LibrePortal having to be told.
    #
    # The invite is single-use and consumed by this create: Stoat stamps it
    # used/claimed_by, so it cannot become a spare key left under the mat.
    if [[ "$out" == *MissingInvite* ]]; then
        local code
        code=$(_stoatMongo 'const c = "LP" + Math.random().toString(36).slice(2, 10).toUpperCase();
db.account_invites.insertOne({_id: c, used: false});
print(c);' | tr -dc 'A-Z0-9')
        if [[ -z "$code" ]]; then
            isError "Stoat is invite-only and an invite could not be created."
            return 1
        fi
        body="{\"email\":$(_stoatJson "$email"),\"password\":$(_stoatJson "$pass"),\"invite\":$(_stoatJson "$code")}"
        out=$(runFileOp curl -sS --max-time 20 -X POST "${api}/auth/account/create" \
                -H 'Content-Type: application/json' -d "$body" 2>&1)
        # Do not leave an unused invite behind if the create still failed.
        [[ -n "$out" ]] && _stoatMongo "db.account_invites.deleteOne({_id: $(_stoatJson "$code"), used: false})" >/dev/null 2>&1
    fi

    # A successful create returns 204 with no body; anything printed is an error.
    if [[ -n "$out" && "$out" != *'"result"'* ]]; then
        isError "Stoat account create failed: $(printf '%s' "$out" | tr -d '\n' | head -c 200)"
        return 1
    fi

    out=$(runFileOp curl -sS --max-time 20 -X POST "${api}/auth/session/login" \
            -H 'Content-Type: application/json' -d "$body" 2>&1)
    token=$(printf '%s' "$out" | python3 -c 'import sys,json
try: print(json.load(sys.stdin).get("token",""))
except Exception: print("")' 2>/dev/null)
    if [[ -z "$token" ]]; then
        isError "Stoat login after create failed: $(printf '%s' "$out" | tr -d '\n' | head -c 200)"
        return 1
    fi

    out=$(runFileOp curl -sS --max-time 20 -X POST "${api}/onboard/complete" \
            -H 'Content-Type: application/json' -H "X-Session-Token: ${token}" \
            -d "{\"username\":$(_stoatJson "$user")}" 2>&1)
    if [[ "$out" == *'"type"'*'"error"'* || "$out" == *UsernameTaken* || "$out" == *InvalidUsername* ]]; then
        isError "Stoat onboarding failed for '${user}': $(printf '%s' "$out" | tr -d '\n' | head -c 200)"
        return 1
    fi
    return 0
}

_stoatMongo() {
    runFileOp docker exec -i stoat-database mongosh revolt --quiet --eval "$1" 2>&1
}

_stoatMongoFailed() {
    local out="$1" what="$2"
    # mongosh reports failures as a thrown error rather than a non-zero exit in
    # --eval mode, so match on the text.
    if [[ "$out" == *MongoServerError* || "$out" == *ReferenceError* || "$out" == *TypeError* ]]; then
        isError "$what failed: $(printf '%s' "$out" | head -2 | tr '\n' ' ')"
        return 0
    fi
    return 1
}

# Accounts and profiles are separate collections sharing an _id: `accounts` holds
# the login (email, disabled flag), `users` the profile (username, discriminator).
# Neither alone is a useful view, so join them.
authAdapter_stoat_listUsers() {
    local out
    out=$(_stoatMongo '
const users = db.users.find({}, {username:1, discriminator:1, display_name:1}).toArray();
const byId = {};
db.accounts.find({}, {email:1, disabled:1}).toArray().forEach(a => byId[a._id] = a);
users.forEach(u => {
  const a = byId[u._id] || {};
  const handle = u.username + (u.discriminator ? "#" + u.discriminator : "");
  const state = a.disabled ? " (disabled)" : "";
  // EZ_USER<TAB>identifier<TAB>display<TAB>roles, as the WebUI modal expects.
  // Email first where there is one: it is the field a row action prefills.
  print("EZ_USER\t" + (a.email || handle) + "\t" + handle + "\t" + (a.disabled ? "disabled" : "user"));
});
print("LP_TOTAL:" + users.length);
')
    _stoatMongoFailed "$out" "Listing users" && return 1

    local line total=0
    while IFS= read -r line; do
        case "$line" in
            EZ_USER*) IFS=$'\t' read -r _ ident handle state <<< "$line"
                      # The marker line has to reach the task log for the WebUI
                      # user-list modal to build its rows from.
                      printf '%s\n' "$line"
                      printf '  %-30s %-24s %s\n' "$ident" "$handle" "$state" ;;
            LP_TOTAL:*) total="${line#LP_TOTAL:}" ;;
        esac
    done <<< "$out"

    if [[ "$total" == "0" ]]; then
        isNotice "No Stoat accounts yet — the first person to register becomes the instance owner."
        return 0
    fi
    isSuccessful "$total Stoat account(s)."
}

# Disabling is Stoat's own reversible state, not a hand-rolled hack: the account
# stays intact and its messages stay readable, the holder just cannot log in.
_stoatSetDisabled() {
    local who="$1" disabled="$2" verb="$3"
    [[ -z "$who" ]] && { isError "A username or email is required."; return 1; }

    local out
    out=$(_stoatMongoWho "$who" "$disabled")
    _stoatMongoFailed "$out" "$verb $who" && return 1
    [[ "$out" == *LP_MISSING* ]] && { isError "No Stoat account matching '$who'."; return 1; }
    [[ "$out" != *LP_OK* ]] && { isError "$verb $who failed: $out"; return 1; }
    return 0
}

# Kept separate so the account lookup (by email on `accounts`, or by username on
# `users`) lives in one place.
_stoatMongoWho() {
    local who="$1" disabled="$2"
    _stoatMongo "
const who = $(printf '%s' "$who" | python3 -c 'import sys,json;print(json.dumps(sys.stdin.read()))');
let acct = null;
if (who.includes('@')) {
  acct = db.accounts.findOne({email: who});
} else {
  const u = db.users.findOne({username: who});
  if (u) acct = db.accounts.findOne({_id: u._id});
}
if (!acct) { print('LP_MISSING'); } else {
  db.accounts.updateOne({_id: acct._id}, {\$set: {disabled: $disabled}});
  print('LP_OK');
}
"
}

authAdapter_stoat_deleteUser() {
    local who="$1"
    _stoatSetDisabled "$who" "true" "Disabling" || return 1
    isSuccessful "Stoat account '$who' disabled — they can no longer sign in. Re-enable it with the Enable tool."
    isNotice "Their existing sessions are not revoked by this; restart the app to force everyone to re-authenticate."
}

authAdapter_stoat_enableUser() {
    local who="$1"
    _stoatSetDisabled "$who" "false" "Enabling" || return 1
    isSuccessful "Stoat account '$who' re-enabled."
}

authAdapter_stoat_createUser() {
    local email="$1" pass="$2" user="$3"
    [[ -z "$email" ]] && { isError "An email is required."; return 1; }
    [[ -z "$pass" ]] && pass=$(generateRandomPassword)
    # Stoat needs a handle as well as a login. Derive one from the email's local
    # part when the caller did not supply it, so the generic "create user" form
    # (which only asks for email + password) still produces a usable account
    # rather than one stuck on the pick-a-username screen.
    if [[ -z "$user" ]]; then
        user="${email%%@*}"
        user="${user//[^a-zA-Z0-9_.]/}"
    fi

    local api
    api=$(_stoatApiLocal "${CFG_STOAT_APP_NAME:-stoat}") || {
        isError "Could not work out Stoat's local API address."; return 1; }

    _stoatCreateAccount "$api" "$email" "$pass" "$user" || return 1

    # Keep the config truthful when this IS the configured owner: an install that
    # could not reach the API leaves those fields describing an account that does
    # not exist, and creating it by hand afterwards should reconcile the two.
    if [[ "$email" == "${CFG_STOAT_ADMIN_EMAIL:-}" ]]; then
        authPersistCfg stoat ADMIN_PASSWORD "$pass"
        authPersistCfg stoat ADMIN_USERNAME "$user"
    fi
    isSuccessful "Stoat account created — Handle: $user — Email: $email — Password: $pass"
}

# Reset a password WITHOUT touching the hash ourselves.
#
# authifier already owns a reset flow: an account carries a password_reset token,
# and PATCH /auth/account/reset_password trades that token for a new password —
# hashing it with exactly the parameters the verifier expects, because it is the
# same code that verifies. So the only thing written directly is the token, which
# is inert on its own; Stoat does the part that has to be right.
#
# The alternative, writing an argon2 string into the account document, would mean
# reproducing $argon2i$v=19$m=4096,t=3,p=1 by hand — and a near miss there is
# silent, locking the holder out with no error at the time.
authAdapter_stoat_setPassword() {
    local who="$1" pass="$2"
    [[ -z "$who" ]] && { isError "A username or email is required."; return 1; }
    [[ -z "$pass" ]] && pass=$(generateRandomPassword)

    local api
    api=$(_stoatApiLocal "${CFG_STOAT_APP_NAME:-stoat}") || {
        isError "Could not work out Stoat's local API address."; return 1; }

    # Short-lived and single-use: the reset endpoint consumes it, and the expiry
    # bounds the window if the endpoint is never reached.
    local token
    token="lp$(tr -dc 'a-z0-9' </dev/urandom | head -c 40)"

    local out
    out=$(_stoatMongo "
const who = $(_stoatJson "$who");
let acct = null;
if (who.includes('@')) {
  acct = db.accounts.findOne({email: who});
} else {
  const u = db.users.findOne({username: who});
  if (u) acct = db.accounts.findOne({_id: u._id});
}
if (!acct) { print('LP_MISSING'); } else {
  db.accounts.updateOne({_id: acct._id}, {\$set: {password_reset: {token: $(_stoatJson "$token"), expiry: new Date(Date.now() + 600000).toISOString()}}});
  print('LP_OK');
}
")
    _stoatMongoFailed "$out" "Password reset for $who" && return 1
    [[ "$out" == *LP_MISSING* ]] && { isError "No Stoat account matching '$who'."; return 1; }
    [[ "$out" != *LP_OK* ]] && { isError "Password reset for $who failed: $out"; return 1; }

    out=$(runFileOp curl -sS --max-time 20 -X PATCH "${api}/auth/account/reset_password" \
            -H 'Content-Type: application/json' \
            -d "{\"token\":$(_stoatJson "$token"),\"password\":$(_stoatJson "$pass")}" 2>&1)
    if [[ -n "$out" ]]; then
        # Clear the token so a failed attempt does not leave a live reset behind.
        _stoatMongo "db.accounts.updateOne({\$or:[{email:$(_stoatJson "$who")}]}, {\$unset:{password_reset:''}})" >/dev/null 2>&1
        isError "Stoat rejected the new password: $(printf '%s' "$out" | tr -d '\n' | head -c 200)"
        return 1
    fi

    if [[ "$who" == "${CFG_STOAT_ADMIN_EMAIL:-}" || "$who" == "${CFG_STOAT_ADMIN_USERNAME:-}" ]]; then
        authPersistCfg stoat ADMIN_PASSWORD "$pass"
    fi
    isSuccessful "Stoat password set for $who — New password: $pass"
    isNotice "Existing sessions stay valid; restart the app to force a re-login."
}