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

#
# Class Diary for Diary Management Application.
#

require_relative 'ldap_record'
require_relative 'project'
require_relative 'diary_policy'
require_relative 'diary_datamapper'

DIARY_TEMPLATE = AmritaTemplate.new("diary.html")

def debug_log(msg)
    STDERR.puts "DEBUG: " + msg
end

def show_action_button(value, name)
    button = "<button type=\"submit\" name=\"diary:action:verb\" "
    button += "value=\"" + value + "\""
    button += " class=\"btn btn-primary btn-sm\" _id=\"edit\">" + name + "</button>"

    return button
end

def show_checkbox(name, checked)
    button = "<input type=\"checkbox\" name=\"diary:list:" + name + "\" class=\"form-check-input\" _id=\"" + name + "\" "
    button += "checked" if checked[0] == "on"
    button += ">"

    return noescape { button }
end

def transform_links(prj, text)
    if prj and text
        text = prj.transform_links(text)
    end

    return noescape { text }
end

# All timestamps in database are in UTC, so we convert them to localtime
# before printing if they are valid
class DbTime
    @@offset = DateTime.now.offset

    def DbTime.now
        # DBI used previously DBI::Timestamp for mapping SQL DATETIME,
        # now it is deprecated, DateTime is used
        if DBI::VERSION >= "0.4"
            DateTime.now.new_offset(0)
        else
            Time.now.utc
        end
    end

    def initialize(t)
        @time = t
    end

    def to_s
        if @time.is_a? DBI::Timestamp
            @time.to_time.localtime.strftime("%Y-%m-%d %H:%M:%S")
        elsif @time.is_a? DateTime and @time.mjd > 0
            @time.new_offset(@@offset).strftime("%Y-%m-%d %H:%M:%S")
        else
            "<N/A>"
        end
    end
end

class DiaryState
    NORMAL = 0
    REQ_APPROVAL = 1
    APPROVED = 2
    REJECTED = 3
    DENIED = 4

    def DiaryState.valid(value)
        value.to_i == NORMAL || value.to_i == APPROVED
    end

    def initialize(x)
        @value = x
    end

    def to_s
        case @value
            when NORMAL then "regular"
            when REQ_APPROVAL then "requires approval"
            when APPROVED then "approved"
            when REJECTED then "rejected"
            when DENIED then "denied"
            else "unknown"
        end
    end

    def to_html
        state_name = to_s
        @value == NORMAL ? state_name :
                           Amrita.e(:span, :class =>
                             "state-" + state_name.tr_s(' ','-')){ state_name }
    end
end

class DiaryMapper < DataMapper
    def initialize
        super("diary")
    end

    def instantiate(id, attributes)
        Diary.new(id, attributes)
    end
end

class DiaryPerson
    attr_reader :person
    attr_accessor :hours
    attr_accessor :records
    attr_accessor :lag
    attr_accessor :week

    def initialize(person)
        @person = person
        @hours = 0
        @records = 0
        @lag = 0
        @week = Hash.new
        Date::ABBR_DAYNAMES.each { |x| @week[x] = {:hours => 0, :records => 0} }
    end

    def register(hours, ddate, created)
        @hours += hours.to_i
        @records += 1

        # We assume that 20:00 is the rough time people submit the diary
        @lag += (created - (ddate + Rational(20, 24)))

        week_day_name = Date::ABBR_DAYNAMES[ddate.wday]
        @week[week_day_name][:hours] += hours.to_i
        @week[week_day_name][:records] += 1
    end

    def lag_to_html
        average_lag = (@lag / @records).round(1).to_f
        average_lag = 0 if average_lag < 0

        if average_lag > 5
            css_style = 'text-danger'
        elsif average_lag > 2
            css_style = 'text-warning'
        elsif average_lag < 0.3
            css_style = 'text-muted'
        else
            css_style = 'text-body'
        end

        noescape { "<span class=\"" + css_style + "\">" + average_lag.to_s + "</span>" }
    end

    def week_to_html
        out = ""
        @week.each { |key, record|
            if record[:hours] > 0
                out = out + key + ": " + record[:hours].to_s + " "
            end
        }
        out
    end

    def day_to_html(day, d_start, d_end)
        # calculate number of days between s_date and e_date
        day_number = DateTime.parse(day).wday
        days_list = (d_start..d_end).to_a.select { |d| day_number == d.wday }
        number_of_days = days_list.count

        if not @week.has_key?(day) or @week[day][:records] == 0
            ""
        else
            Rational(@week[day][:hours], number_of_days).round(+1).to_f.to_s
        end
    end
end

class Diary
    @@mapper = nil
    def self.mapper
        return @@mapper unless @@mapper.nil?
        @@mapper = DiaryMapper.new
    end

    def initialize(id = nil, values = nil)
        @id = id
        @attributes = values ? values : Hash.new
        @approval_note = nil
    end

    def self.get(id)
        mapper.find(id)
    end

    def project
        @attributes.has_key?("prj_id") ?
            Project.get(@attributes["prj_id"]) : nil
    end

    def who
        Person.find_or_create(@attributes["who"])
    end

    def approval_note
        policy = DiaryEnv.instance.policy
        return [] if (not policy.can_edit?(project, who) and
                      not policy.can_approve?(project, who)) or
                     DiaryState.valid(@attributes["state"].to_i)

        @approval_note = DataMapper.database.select_all(
                "select * from approval_note where id = ?", @id
                                    ).collect { |row| row.to_h }
        return @approval_note
    end

    def self.approve_all(prj, who)
        DataMapper.database.do("update diary set state = ? where prj_id = ? " +
                "AND who = ? AND state IN (?,?)", DiaryState::APPROVED,
                prj.id, who, DiaryState::REQ_APPROVAL, DiaryState::REJECTED)
    end

    def destroy
    end

    def [](tag)
        @attributes[tag]
    end

    def []=(tag, value)
        @attributes[tag] = value
    end

    def self.predict_project(who)
        # TODO: select the most used of N last entries
        last_diary = DataMapper.database.select_one(
                     "SELECT prj_id FROM diary " +
                     "WHERE who=? ORDER BY ddate DESC " +
                     "LIMIT 1", who.uid)
        return last_diary ? last_diary[0].to_i : nil
    end

    def self.find(args)
        who = args[:who]
        prj_id = args[:prj_id]
        customer = args[:customer]
        policy = DiaryEnv.instance.policy

        dates = args[:ddate]
        raise ArgumentError unless dates.is_a? Range
        query_clause = "  where ddate >= ? and ddate <= ?"
        query_args = [dates.first, dates.last]

        if policy.restriction.include?(:project)
            prj_list = policy.project_list.collect {|prj| prj.id }
            prj_list = prj_list & [prj_id] if prj_id
            return [] if prj_list.empty?
            query_clause += " AND prj_id IN (" +
                            prj_list.collect { "?" }.join(",") + ")"
            query_args += prj_list
        elsif prj_id
            query_clause += " AND prj_id = ?"
            query_args = query_args << prj_id
        end

        if policy.restriction.include?(:engineer)
            eng_list = policy.engineer_list.collect {|eng| eng.uid }
            eng_list = eng_list & [who] if who
            return [] if eng_list.empty?
            query_clause += " AND who IN (" +
                            eng_list.collect { "?" }.join(",") + ")"
            query_args += eng_list
        elsif who
            query_clause += " AND who = ?"
            query_args = query_args << who
        end

        if customer
            query_clause += " AND customer = ?"
            query_args = query_args << customer
        end

        DataMapper.database.select_all("select diary.*, project.customer, " +
            " project.leader, project.manager, diary.id as id" +
            ", diary.state as state" +
            " from diary left join project on diary.prj_id = project.id" +
            query_clause + " order by ddate, prj_id, who",
            *query_args).collect do |row|
                self.new(row["id"], row.to_h)
        end
    end

    def self.for_approve(who)
        DataMapper.database.select_all("select *, diary.id as id from" +
            " diary inner join approval on approval.who = diary.who and" +
            " approval.prj_id = diary.prj_id left join project on" +
            " diary.prj_id = project.id where approval.approver = ?" +
            " and diary.state = ? order by diary.ddate",
            who.uid, DiaryState::REQ_APPROVAL).collect do |row|
                self.new(row["id"], row.to_h)
        end
    end

    def self.add_approval_note(id, message)
        if message.is_a?(String) and message.length > 0
            DataMapper.database.do(
                    "insert into approval_note(id,created,author,note) " +
                    "values (?,?,?,?)", id, DbTime.now,
                    DiaryEnv.instance.user.uid, message)
        end
    end
end

class DiaryUI
    def initialize(cgi)
        @cgi = cgi
        @user = DiaryEnv.instance.user
        @policy = DiaryEnv.instance.policy
        @diary_table = SQL_Cache.new(DataMapper.database, "diary", "")
        @projects = nil
    end

    # Array of projects suitable for diary entries
    def projects
        return @projects unless @projects.nil?
        @projects = Project.all(:prj_status => 'ACTIVE')
    end

    def project_list
        projects.sort.collect do |prj|
            [prj.id, prj.to_s]
        end
    end

    def customer_list
        projects.collect {|prj| prj.customer}.uniq.sort.collect do |org|
            [org.uid, org.to_s]
        end
    end

    def show_total(list, d_start, d_end, detailed)
        totals = Hash.new
        totals[:customer] = Array.new
        totals[:person]  = Array.new
        totals[:hours] = 0

        persons = Hash.new
        projects = Hash.new
        customers = Hash.new
        list.each do |x|
            who = Person.find_or_create(x["who"])
            prj = Project.get(x["prj_id"])
            next if not @policy.can_account?(prj)
            if DiaryState.valid(x["state"].to_i)
                projects[prj] =
                    projects[prj].to_i + x["hours"].to_i
                if not persons[who]
                    persons[who] = DiaryPerson.new(who)
                end
                persons[who].register(x["hours"], x["ddate"], x["created"])
                totals[:hours] += x["hours"].to_i
            end
        end
        projects.sort.each do |item|
            prj = item[0]
            org = Organization.find(prj["customer"])
            customers[org] = Array.new unless customers[org]
            customers[org].push({:name => prj["name"],
                                 :customer => prj["customer"],
                                 :tag => prj["tag"],
                                 :hours => item[1]})
        end
        customers.sort.each do |item|
            hours = item[1].inject(0) { |sum, value| sum += value[:hours] }
            totals[:customer].push({:name => item[0].to_s,
                                    :hours => hours,
                                    :project => item[1]})
        end
        if detailed
            persons.sort.each do |item|
                dp = item[1]
                totals[:person].push({:name => item[0].to_html,
                                      :hours => dp.hours,
                                      :delay => dp.lag_to_html,
                                      :mon_stat => dp.day_to_html('Mon', d_start, d_end),
                                      :tue_stat => dp.day_to_html('Tue', d_start, d_end),
                                      :wed_stat => dp.day_to_html('Wed', d_start, d_end),
                                      :thu_stat => dp.day_to_html('Thu', d_start, d_end),
                                      :fri_stat => dp.day_to_html('Fri', d_start, d_end),
                                      :sat_stat => dp.day_to_html('Sat', d_start, d_end),
                                      :sun_stat => dp.day_to_html('Sun', d_start, d_end),
                                     })
            end
        else
            persons.sort.each do |item|
                totals[:person].push({:name => item[0].to_html,
                                      :hours => item[1].hours,
                                     })
            end
        end

        return totals[:hours] > 0 ? totals : nil
    end
    private :show_total

    def show_approval_notes(entry)
        return nil if entry.approval_note.empty?
        entry.approval_note.collect do |note|
            {
                :created => DbTime.new(note["created"]).to_s,
                :author => note["author"],
                :note => note["note"]
            }
        end
    end

    def show_one(values = nil, edit = false, approve = false)
        if (values == nil)
            edit = add = true
            values = Diary.new
        else
            add = false
            edit = false if values["state"].to_i == DiaryState::DENIED
        end
        edit ||= add

        # Set project to the last edited one (for new entries)
        if not values.project
            values["prj_id"] = Diary.predict_project(@user)
        end

        prj = Project.get(values["prj_id"].to_i)
        if edit
            edit_data = {
                :hiddens => @cgi.hiddens(@cgi.tree_flatten(["diary",
                            "list"]).delete_if do |x|
                                x == ["diary:list:edit", values["id"].to_s]
                            end),
                :date => MyCGI::select_date_e("diary:edit:ddate",
                         values["ddate"] || Date.today, edit),
                :person => MyCGI::list_options(
                            @policy.engineer_list.collect {|x| [x.uid, x.to_s]},
                           (values["who"] || @user.uid)),
                :hours => a(:value => values["hours"]),
                :project => MyCGI::list_options(project_list,
                            prj ? prj.id : ""),
                :descr => values["descr"]
            }
            edit_data[:id] = a(:value => values["id"]) if values["id"]
            if prj and prj.approvals.has_key?(values["who"])
                edit_data[:approval] = Hash.new
                edit_data[:approval][:appnote] = show_approval_notes(values)
            end
            return { :edit => edit_data }
        else
            view = {
                :id => a(:name => values["id"]),
                :hiddens => @cgi.hiddens(@cgi.tree_flatten(["diary", "list"])),
                :date => MyCGI::select_date_e("diary:edit:ddate",
                    values["ddate"] || Date.today, edit),
                :person => Person.find_or_create(values["who"]).to_html,
                :project_name => prj["name"],
                :project => prj["customer"]+ "/" + prj["tag"],
                :descr => transform_links(prj, values["descr"]),
                :edit_id => a(:value => values["id"]),
                :modified => DbTime.new(values["modified"]).to_s,
                :created => DbTime.new(values["created"]).to_s,
                :state => DiaryState.new(values["state"].to_i).to_html
            }
            view[:hours] = values["hours"].to_s + " h" if
                @policy.can_account?(prj)
            view[:appnote] = show_approval_notes(values) if
                             not values.approval_note.empty?
            if @policy.can_edit?(prj, Person.find(values["who"])) or approve
                view[:edit] = { }
                return { :view => a(:action => "#" +
                                MyCGI::element_id(values["id"])){ view }}
            else
                return { :view_only => view }
            end
        end
    end
    private :show_one

    def menu
        {
            :start_date => MyCGI::select_date_e("diary:list:start",
                                                @cgi.tree_params["diary"]["list"]["start"]),
            :end_date => MyCGI::select_date_e("diary:list:end",
                                @cgi.tree_params["diary"]["list"]["end"]),
            :project => MyCGI::list_options([["*", "- All -"]] +
                                            project_list,
                        @cgi.tree_params["diary"]["list"]["prj_id"]),
            :customer => MyCGI::list_options([["*", "Customer: all"]] +
                           customer_list,
                        @cgi.tree_params["diary"]["list"]["customer"]),
            :who => MyCGI::list_options([["*", "Engineer: all"]] +
                        @policy.engineer_list.collect {|x| [x.uid, x.to_s]},
                        @cgi.tree_params["diary"]["list"]["who"]),
            :newest_first => show_checkbox("newest_first", @cgi.tree_params["diary"]["list"]["newest_first"]),
            :just_stats => show_checkbox("just_stats", @cgi.tree_params["diary"]["list"]["just_stats"])
        }
    end

    def show
        diary_data = Hash.new
        MyCGI::add_commons(diary_data)
        diary_data[:menu] = menu
        diary_data[:new] = show_one() if @user.local?

        if @cgi.tree_params["do"] == "diary"
            d_start = MyCGI::hash2date(
                @cgi.tree_params["diary"]["list"]["start"])
            d_end = MyCGI::hash2date(
                @cgi.tree_params["diary"]["list"]["end"])
            prj_id = @cgi.tree_params["diary"]["list"]["prj_id"][0].to_i
            prj_id = nil if prj_id <= 0
            customer = @cgi.tree_params["diary"]["list"]["customer"][0]
            customer = nil if not Organization.exists?(customer)
            who = @cgi.tree_params["diary"]["list"]["who"][0].strip.downcase
            who = nil if who == "" or who == "*"

            list_approval = Diary.for_approve(@user)
            if list_approval.length > 0
                diary_data[:massapproval] = a(:__id__)

                diary_data[:approvals] = { :entries =>
                    list_approval.inject([]) do |data, item|
                        data << a(:__id__ => MyCGI::element_id(item["id"])){
                            show_one(item, false, true)}
                    end
                }
            end

            list = Diary.find(:who => who,
                       :prj_id => prj_id,
                       :customer => customer,
                       :ddate => (d_start..d_end))
            list.delete_if do |entry|
                not DiaryState.valid(entry["state"]) and
                not @policy.can_edit?(entry.project, entry.who)
            end
            if list.length > 0
                if @policy.is_director?
                    diary_data[:detailed_totals] = show_total(list, d_start, d_end, @policy.is_director?)
                else
                    diary_data[:totals] = show_total(list, d_start, d_end, false)
                end

                if @cgi.tree_params["diary"]["list"]["just_stats"][0] != "on"
                    if @cgi.tree_params["diary"]["list"]["newest_first"][0] == "on"
                        list.reverse!
                    end
                    diary_data[:details] = {
                        :entries =>
                        list.inject([]) do |data, item|
                            data << a(:__id__ => MyCGI::element_id(item["id"])){
                                show_one(item,
                                         @cgi.tree_params["diary"]["list"]["edit"].
                                             include?(item["id"].to_s)) }
                        end
                    }
                else
                    diary_data[:nodata] = {}
                end
            else
                diary_data[:nodata] = {}
            end
        end
        s = String.new
        DIARY_TEMPLATE.expand(s, diary_data)
        s
    end

    def approve_item(id, action)
        entry = @diary_table[id].dup
        raise "Entry does not exist" if not entry
        raise "You have no rights to approve diary entries for " +
              "#{Person.find(entry["who"]).to_s} in this project." if
            not @policy.can_approve?(Project.get(entry["prj_id"]),
                                     Person.find_or_create(entry["who"]))

        entry["state"] = case action
                         when "Approve" then DiaryState::APPROVED
                         when "Deny" then DiaryState::DENIED
                         when "Reject" then DiaryState::REJECTED
                         end
        @diary_table.modify(id, entry)

        return if not @cgi.tree_params["diary"].include?("edit")
        data = @cgi.tree_params["diary"]["edit"]
        Diary.add_approval_note(id, data["approval"])
    end

    def approval_action
        id = @cgi.tree_params["diary"]["action"]["id"].to_i
        action = @cgi.tree_params["diary"]["action"]["verb"]

        approve_item(id, action)
    end

    def list_approval_action
        list_action = @cgi.tree_params["diary"]["action"]["verb"]
        action = case list_action
                 when "ApproveAll" then "Approve"
                 when "DenyAll" then "Deny"
                 when "RejectAll" then "Reject"
                 end

        list_approval = Diary.for_approve(@user)
        if list_approval.length > 0
            list_approval.each do |item|
                approve_item(item["id"], action)
            end
        end
    end

    def action
        debug_log(@cgi.tree_params.inspect)

        # Delete an entry
        if @cgi.tree_params["diary"]["action"]["verb"] == "Delete"
            id = @cgi.tree_params["diary"]["action"]["id"].to_i
            entry = Diary.get(id)
            raise "You are trying to delete diary entry #{id} " +
                  "which does not exist." if not entry

            raise "You have no rights to delete diary entries for " +
                  "#{entry.who.to_s} in this project." if
                  not @policy.can_edit?(entry.project, entry.who)

            raise NeedConfirm.new("delete"),
                  "You are deleting diary entry of " +
                  "#{entry.who.to_s} for #{entry["ddate"]}!" if
                  not DiaryEnv.confirmed?("delete")

            @diary_table.delete(id)
            return
        end

        if @cgi.tree_params["diary"]["action"]["verb"] == "ApproveAll" or
           @cgi.tree_params["diary"]["action"]["verb"] == "RejectAll" or
           @cgi.tree_params["diary"]["action"]["verb"] == "DenyAll"
            list_approval_action
            return
        end


        if @cgi.tree_params["diary"]["action"]["verb"] == "Approve" or
           @cgi.tree_params["diary"]["action"]["verb"] == "Reject" or
           @cgi.tree_params["diary"]["action"]["verb"] == "Deny"
            approval_action
            return
        end

        # After adding/editing entry
        return if not @cgi.tree_params["diary"].include?("edit")
        data = @cgi.tree_params["diary"]["edit"].dup
        # normalize input
        data["who"].strip!
        data["who"].downcase!
        raise "No such person #{data["who"]} " if not Person.exists?(data["who"])
        data["prj_id"] = data["prj_id"].to_i
        prj = Project.get(data["prj_id"])
        who = Person.find(data["who"])
        raise "No such project #{data["prj_id"]}" unless prj

        raise "Project #{prj.to_s} is terminated" if
            prj["prj_status"] == "TERMINATED"

        raise "You have no rights to add/change diary records " +
              "for #{who.to_s}." if not @policy.can_edit?(prj, who)

        data["hours"] = data["hours"].to_i
        data["ddate"] = MyCGI::hash2date(data["ddate"])

        raise NeedConfirm.new("future"),
              "You're posting diary for the future" if
              data["ddate"] > Date.today and not DiaryEnv.confirmed?("future")

        raise "Don't use non-English symbols - not all customers can read Russian" if
            not data["descr"].ascii_only?

        raise "Please use at least 10 characters in diary entry description" if
            data["descr"].length < 10

        # Check total hours
        total = DataMapper.database.select_one(
                        "SELECT SUM(hours) FROM diary " +
                        "WHERE who=? AND ddate=?" +
                        (data.include?("id") ?
                         " AND id<>#{data["id"]}" : ""),
                        *([data["who"], data["ddate"]]))[0].to_i +
                data["hours"]
        raise "You have more than 24 hours " +
              "for #{data["ddate"]}" if total > 24

        raise NeedConfirm.new("overwork"),
              "You have more (#{total}) than 15 hours " +
              "for #{data["ddate"]}" if
              total > 15 and not DiaryEnv.confirmed?("overwork")

        if @policy.needs_confirmation?(prj, who)
            raise NeedConfirm.new("past"), "You are " +
                                           (data.include?("id") ? "editing" : "adding") +
                                           " a diary record for #{data["ddate"]} that is in the past" if
                data["ddate"] < Date.today and not DiaryEnv.confirmed?("past")
        end

        raise NeedConfirm.new("progressive"),
            "You are trying to add #{total} hours " +
            "for today, while it is just #{Time.now.hour} hours now" if
            data["ddate"] == Date.today and total > Time.now.hour and
            not DiaryEnv.confirmed?("progressive")

        data["state"] = (prj.approvals.has_key?(data["who"]) ?
                        DiaryState::REQ_APPROVAL : DiaryState::NORMAL)

        # Automatically reject creating (not editing) too old entry
        if not data.include?("id") and
           data["state"] == DiaryState::REQ_APPROVAL and
           Date.today - data["ddate"] > DiaryEnv::DIARY_MAX_AGE
            if DiaryEnv.confirmed?("too_old")
                data["state"] = DiaryState::REJECTED
            else
                raise NeedConfirm.new("too_old"),
                      "Date is too old, entry will be rejected"
            end
        end

        # Insert/replace DB entry
        data["modified"] = DbTime.now
        if data.include?("id")
            data.delete("id")
            if data["hours"].to_i == 0
                @diary_table.delete(@cgi.tree_params["diary"]["edit"]["id"])
            else
                @diary_table.modify(@cgi.tree_params["diary"]["edit"]["id"],
                    data)
            end
        else
            raise "You should specify at least 1 hour" if data["hours"] < 1
            raise "You are inserting a duplicate diary record!" if
                DataMapper.database.select_one(
                                "SELECT COUNT(*) FROM diary WHERE " +
                                "who = ? and descr = ? and hours = ? " +
                                "and ddate =?",
                                *([data["who"], data["descr"],
                                data["hours"], data["ddate"]]))[0].to_i > 0
            data["created"] = data["modified"]
            @diary_table.create(data)
        end

        Diary.add_approval_note(@cgi.tree_params["diary"]["edit"]["id"].to_i,
                          data["approval"]) if
                          data["approval"] and data["approval"].length > 0

        # Adjust start/end day of the list to make new record visible
        @cgi.tree_params["diary"]["list"]["start"] =
             MyCGI::date2hash(data["ddate"]) if data["ddate"] <
             MyCGI::hash2date(@cgi.tree_params["diary"]["list"]["start"])
        @cgi.tree_params["diary"]["list"]["end"] =
             MyCGI::date2hash(data["ddate"]) if data["ddate"] >
             MyCGI::hash2date(@cgi.tree_params["diary"]["list"]["end"])
    end
end