#!/bin/bash

# Mattermost user management, via mmctl in local mode.
#
# mmctl is the current CLI — not the long-deprecated `mattermost` binary that
# used to ship alongside it. It lives in the image at /usr/local/bin/mmctl and
# is the only reason these tools are possible at all: the v11 image is
# distroless, with no shell, so every call has to be a direct exec of a binary
# with no pipes, redirects or shell built-ins available.
#
# --local talks to the server's unix socket instead of the REST API, which means
# no credentials to store, no token to expire, and it keeps working even when
# the admin account is locked out or the site URL is wrong.

_mmctl() {
    runFileOp docker exec -i mattermost-service mmctl --local "$@" 2>&1
}

# mmctl exits non-zero on failure and writes the reason to stderr, which _mmctl
# folds into stdout.
#
# Its errors are multi-line — a summary ("Error: 1 error occurred:") followed by
# an indented bullet carrying the part that actually explains anything. Reporting
# only the first line threw the useful half away, so prefer the bullet when
# there is one.
_mmctlFailed() {
    local out="$1" what="$2"
    [[ "$out" != *"Error:"* ]] && return 1
    local detail
    detail=$(printf '%s' "$out" | sed -n 's/^[[:space:]]*\*[[:space:]]*//p' | head -1)
    [[ -z "$detail" ]] && detail=$(printf '%s' "$out" | grep -m1 'Error:' | sed 's/.*Error: *//')
    isError "$what failed: $detail"
    return 0
}

authAdapter_mattermost_createUser() {
    local email="$1" password="$2" username="$3" isAdmin="$4"
    [[ -z "$email" ]] && { isError "An email address is required."; return 1; }
    [[ -z "$username" ]] && username="${email%@*}"
    [[ -z "$password" ]] && password=$(generateRandomPassword)

    # Mattermost usernames are lowercase and restricted to letters, numbers and
    # . - _ — sanitise rather than let the server reject the whole call.
    username=$(printf '%s' "$username" | tr '[:upper:]' '[:lower:]' | tr -c 'a-z0-9._-' '-' | sed 's/^-*//; s/-*$//')
    [[ -z "$username" ]] && username="user"

    local out
    out=$(_mmctl user create --email "$email" --username "$username" --password "$password")
    _mmctlFailed "$out" "Creating $email" && return 1

    if [[ "$isAdmin" == "true" ]]; then
        local promote
        promote=$(_mmctl roles system-admin "$email")
        _mmctlFailed "$promote" "Granting system admin to $email" && return 1
    fi

    isSuccessful "Mattermost user created — Email: $email — Username: $username — Password: $password"
}

authAdapter_mattermost_setPassword() {
    local email="$1" password="$2"
    [[ -z "$email" ]] && { isError "An email address is required."; return 1; }
    [[ -z "$password" ]] && password=$(generateRandomPassword)

    local out
    out=$(_mmctl user change-password "$email" --password "$password")
    _mmctlFailed "$out" "Resetting $email" && return 1

    # Keep the config in step if this is the account the WebUI card advertises.
    [[ "$email" == "${CFG_MATTERMOST_ADMIN_EMAIL:-}" ]] && authPersistCfg mattermost ADMIN_PASSWORD "$password"

    isSuccessful "Mattermost password set for $email — New password: $password"
}

authAdapter_mattermost_listUsers() {
    # --json rather than the human format: it carries `roles` and `delete_at`,
    # which the plain listing does not. There is no --system-admin filter on
    # `user list` (only --inactive), so parsing the text output left every
    # account looking like a plain user.
    local out
    # 200 is mmctl's maximum; asking for more makes it print a warning line
    # BEFORE the JSON, which then fails to parse.
    out=$(_mmctl --json user list --per-page 200)
    _mmctlFailed "$out" "Listing users" && return 1

    local rendered
    rendered=$(printf '%s' "$out" | python3 -c "
import sys, json
# _mmctl folds stderr into stdout, and mmctl prints status lines such as
# 'There are 4 users on local instance' AFTER the JSON as well as warnings
# before it. raw_decode stops at the end of the first complete JSON value and
# ignores whatever trails it, which plain json.loads will not do.
raw = sys.stdin.read()
start = min([i for i in (raw.find('['), raw.find('{')) if i >= 0], default=-1)
users = []
if start >= 0:
    try:
        users, _ = json.JSONDecoder().raw_decode(raw[start:])
    except Exception:
        users = []
if isinstance(users, dict):
    users = users.get('users', [])
for u in users:
    roles = 'admin' if 'system_admin' in (u.get('roles') or '') else 'user'
    if u.get('delete_at'):
        roles += ',deactivated'
    email = u.get('email') or '-'
    name = u.get('username') or '-'
    # EZ_USER<TAB>email<TAB>username<TAB>roles is what the WebUI user-list modal
    # parses; the aligned line after it is for whoever reads the log.
    print('EZ_USER\\t%s\\t%s\\t%s' % (email, name, roles))
    print('  %-30s %-22s %s' % (email, name, roles))
print('LP_TOTAL:%d' % len(users))
" 2>/dev/null)

    local line total=0
    while IFS= read -r line; do
        case "$line" in
            LP_TOTAL:*) total="${line#LP_TOTAL:}" ;;
            *) [[ -n "$line" ]] && printf '%s\n' "$line" ;;
        esac
    done <<< "$rendered"
    isSuccessful "$total Mattermost account(s)."
}

# Mattermost distinguishes deactivate (reversible, frees nothing) from delete
# (permanent, purges content). This is the reversible one: it is what the
# product itself recommends, and a real delete is not undoable from a WebUI
# button click.
authAdapter_mattermost_deleteUser() {
    local email="$1"
    [[ -z "$email" ]] && { isError "An email address is required."; return 1; }

    local out
    out=$(_mmctl user deactivate "$email")
    _mmctlFailed "$out" "Deactivating $email" && return 1
    isSuccessful "Mattermost user '$email' deactivated. Re-enable them from the System Console if needed."
}

authAdapter_mattermost_setAdmin() {
    local email="$1" isAdmin="$2"
    [[ -z "$email" ]] && { isError "An email address is required."; return 1; }

    # `roles system-admin` / `roles member`, NOT `user promote` / `user demote`:
    # those two convert between guest and member accounts and have no bearing on
    # administrator rights at all.
    local out target="false"
    if [[ "$isAdmin" == "true" ]]; then
        target="true"
        out=$(_mmctl roles system-admin "$email")
    else
        out=$(_mmctl roles member "$email")
    fi
    _mmctlFailed "$out" "Changing admin status for $email" && return 1
    isSuccessful "Mattermost user '$email' system admin → $target."
}