# SPDX-License-Identifier: Apache-2.0
# Copyright (C) 2021 OKTET Labs Ltd. All rights reserved.

#
# Class LdapRecord for Diary Management Application.
#

require_relative 'ldap_cache'
require 'net/smtp'

class LdapRecord
    @@connection = nil
    @@cache = {}
    attr_reader :id

    def LdapRecord.setup(args)
        raise "Invalid parameters" unless args.is_a? Hash
        raise "LDAP server is not specified" unless args[:host]
        @@ldap = LDAP::Conn.new(args[:host], args[:port] || LDAP::LDAP_PORT)
        if args[:ver] == 3
          @@ldap.set_option(LDAP::LDAP_OPT_PROTOCOL_VERSION, 3)
        end
        if args[:binddn] != ""
          @@ldap.bind(args[:binddn], args[:bindpw])
        end
        #@@ldap.bind  # Bind is optional for LDAPv3

        raise "LDAP tree root is not specified" unless args[:root]
        raise "LDAP key attribute is not specified" unless args[:key]
        @@connection = LDAP::Cache.new(@@ldap, args[:root],
                LDAP::LDAP_SCOPE_SUBTREE, args[:key])
    end

    def initialize(id)
        raise "LDAP connection is not established" if not @@connection
        @id = id
        @@cache[id] = self
        @attributes = @@connection[id]
    end

    def LdapRecord.find(id)
#        entry = @@cache[id] || (exists?(id) ? new(id) : nil)
#        entry = nil if (entry && !entry.valid?)
#        entry
        return @@cache[id] if valid?(@@cache[id])
        exists?(id) ? new(id) : nil
    end

    def LdapRecord.valid?(entry)
        entry != nil
    end

    def LdapRecord.find_or_create(id)
        @@cache[id] || new(id)
    end

    def LdapRecord.exists?(id)
        @@connection[id] != nil
    end

    def LdapRecord.find_by_filter(filter)
        @@connection.list(filter, "uid").collect { |x| find(x[0]) }.find_all { |x| x }
    end

    def method_missing(method, *args)
        @attributes ? @attributes[method.to_s] : nil
    end
end

class Person < LdapRecord
    MAX_LENGTH = 30

    attr_reader :organization
    def initialize(id)
        super(id)
        @organization = Organization.find_by_name(self.o)
    end

    def Person.exists?(id)
        super(id) && @@connection[id]["objectClass"] == "inetOrgPerson"
    end

    def Person.valid?(entry)
        super(entry) && entry.objectClass == "inetOrgPerson"
    end

    def Person.set_local(o_name, ou_name)
        @@local_o = o_name
        @@local_ou = ou_name
    end

    def to_s
        self.cn || @id
    end

    def to_html
        if not self.cn
            e(:span, :style => "color:red"){ @id }
        elsif self.mail
            e(:a, :href => "mailto:" + self.mail){ self.cn }
        else
            e(:span){ self.cn }
        end
    end

    def local?
        self.o == @@local_o
    end

    def employee?
        local? and self.ou == @@local_ou
    end

    def customer?
        self.o != nil and not local?
    end

    def Person.find_by_org(org_name)
        find_by_filter("(&(o=#{org_name})(objectClass=inetOrgPerson))")
    end

    def <=>(rhs)
        if self.cn
            rhs.cn ? self.cn <=> rhs.cn : -1
        else
            rhs.cn ? 1 : @id <=> rhs.id
        end
    end
end

class Organization < LdapRecord
    def to_s
        self.o || @id
    end

    def to_html
        if not self.o
            e(:span, :style => "color:red"){ @id }
        else
            e(:span){ self.o }
        end
    end

    def Organization.exists?(id)
        super(id) && @@connection[id]["objectClass"] == "organization"
    end

    def Organization.valid?(entry)
        super(entry) && entry.objectClass == "organization"
    end

    def Organization.all
        find_by_filter("(objectClass=organization)")
    end

    def Organization.find_by_name(name)
        return nil unless name.is_a? String
        res = find_by_filter("(&(o=#{name})(objectClass=organization))")
        res ? res[0] : nil
    end

    def <=>(rhs)
        if self.o
            rhs.o ? self.o <=> rhs.o : -1
        else
            rhs.o ? 1 : @id <=> rhs.id
        end
    end
end

class Notifier
    def notify(who, message)
        raise "No such person \"#{who.to_s}\"" if not who.is_a? Person
        msg = "From: Diary Management Application <#{DiaryEnv::SMTP_FROM}>\n" +
              "To: #{who.cn} <#{who.mail}>\n" +
              "Subject: Diary Management\n" +
              "\n" + message
        Net::SMTP.start(DiaryEnv::SMTP_HOST) do |smtp|
            smtp.send_message msg, DiaryEnv::SMTP_FROM, who.mail.untaint
        end
    end
end