-- chat_history - Channel-based history for Chat System
--    (component of Chat System)
-- Template attachment: chat_system
-- Created by: Patrick Ferland
-- Created on: 06/02/2008
 
-- Revision History
    -- 06/02/2008 P.Ferland - Cleanup and documentation
    -- 06/20/2008 J.McNab - Added styling of chat history and login history length
    -- 07/17/2008 P.Ferland - Unpersisted history until fixed (stylesheet can't contain large tables)
    -- 07/22/2008 P.Ferland - Commented attach/detach object blocks
    -- 07/28/2008 P.Ferland - Persisted history - chat is no longer a stylesheet object!
    -- 07/29/2008 P.Ferland - Replaced "-" prefix with system coloration
    -- 09/02/2008 P.Ferland - Changed hardcoded buffer sizes to MAX_SEND_BUFFER_SIZE
    -- 10/08/2008 P.Ferland - OX friendliness pass

-- Constants
WORLD_HISTORY_SCRIPT = '11302:24'
HISTORY_SAVE_TICK = 900000 -- 15-minute save tick

-- Script properties

Define Properties()

    script_description = "Chat History"
    script_long_description = "Manage how your world chat system remembers and displays public chat"
    
    chat_system_history_enabled = 1
    ExposeProperty('chat_system_history_enabled', 'Enable chat channel history?', 'checkbox')
    PersistProperty('chat_system_history_enabled')
    
    chat_system_history_length = 500
    ExposeProperty('chat_system_history_length', 'Number of lines to keep per channel', 'int')
    SetPropRange('chat_system_history_length', 0, 5000)
    
    chat_system_login_history_length = 10
    ExposeProperty('chat_system_login_history_length', 'Number of lines of history to show on login', 'int')
    SetPropRange('chat_system_login_history_length', 0, 100)
    
    chat_system_history_web = 0
    ExposeProperty('chat_system_history_web', 'Allow web view of chat history?', 'checkbox')
    PersistProperty('chat_system_history_web')

    chat_system_history_web_secure = 1
    ExposeProperty('chat_system_history_web_secure', 'Require password for web chat history?', 'checkbox')
    PersistProperty('chat_system_history_web_secure')
    
    chat_system_history_web_password = ''
    ExposeProperty('chat_system_history_web_password', 'Web chat history password')
    PersistProperty('chat_system_history_web_password')
    
    chat_system_history = {}
    PersistProperty('chat_system_history')
    
    chat_system_history_style = ''
    ExposeProperty('chat_system_history_style', 'URL for the location of the stylesheet for your chat history page')
    PersistProperty('chat_system_history_style')
    
    IncludeScript('11302:12') -- chat_utility

end

-- Commands
    -- no commands

-- Triggers

-- System trigger:  called when script is attached (in builder or at instantiation)
Trigger attach()

    SendTo(self, 'chat_system_register_command', 0,
        'history', 'Display 10 lines of history (or /history [number] between 1-1000 for [number] lines of history)', 0, 0)

    -- Begin tick to save chat system history    
    SendTo(self, 'chat_system_history_save', HISTORY_SAVE_TICK)

end

-- System trigger:  called when script is detached
Trigger detach()

    SendTo(self, 'chat_system_unregister_command', 0, 'history')

end

-- Save chat history
Trigger chat_system_history_save_tick()

    if (self.chat_system_history_enabled == 1) then
        SaveToDb(self)
    end
    SendTo(self, 'chat_system_history_save', HISTORY_SAVE_TICK)

end


-- Core "chat system" trigger for sending any message
-- Handling this allows us to process the raw message.  This means that history is NOT profanity-filtered, colored, etc.
Trigger chat_system_send_message(endpoint, message, channel, sender, command)

    -- Quit if chat history is disabled
    if (self.chat_system_history_enabled ~= 1) then
        return
    end

    -- Above all else, be polite.  Do NOT store user channel histories!
    if (string.find(channel, '/user/') ~= nil) then
        return
    end

    local channel_history = self.chat_system_history[channel]
    
    local last_message = ''
    
    if (channel_history ~= nil) then
    
        while ( (#channel_history >= self.chat_system_history_length) and (#channel_history > 0) ) do
            table.remove(channel_history, 1)
        end
        
        last_message = channel_history[#channel_history].msg
        
    else
        self.chat_system_history[channel] = {}
    end
    
    if (message ~= last_message) then
        table.insert( self.chat_system_history[channel], chat_system_history_line(message) )
    end
end

-- /history [lines] command
-- Displays last 10 (or [lines], if provided and a number 1-1000 ) lines of history for current channel
Trigger chat_msg_history(sender, message)

    local channel = chat_system_channel_name('user', sender.name)
    local history = self.chat_system_history[sender.chat_system_current_channel]

    -- Quit if chat history is disabled
    if (self.chat_system_history_enabled == 1) then
    
        local lines = 10
    
        local arguments = {}
        if ( (message ~= nil) and (message ~= '') ) then
            local num = tonumber(message)
            if (num ~= nil) then
                if (num < 1) then
                    lines = 1
                elseif (num > 1000 ) then
                    lines = 1000 
                else
                    lines = num
                end
            end
        end
    
        if (history ~= nil) then
            if (#history < lines) then
                lines = #history
            end
            
            local message = chat_system_format_system_message('- Displaying ' .. lines .. ' lines of history:<br>')
            local pre = ''
            
            local i = 0
            for i = #history - lines + 1, #history do
                message = message .. pre .. chat_system_format_system_message('[' .. history[i].time .. '] ' .. history[i].msg)
                pre = '<br>'
            end
            
            if (string.len(message) > 0) then
                chat_system_send_to_subscribers(self, sender, channel, message, 'history')
            end
        else
            local message = 'No history for channel'
            chat_system_send_to_subscribers(self, sender, channel, chat_system_format_system_message(message), 'history')
        end
        
    else
        local message = 'No history is available'
        chat_system_send_to_subscribers(self, sender, channel, chat_system_format_system_message(message), 'history')
    end
    
    chat_system_set_callback(sender, CHAT_STATUS_CODES.OK, 'OK')

end

-- Local functions

-- Generate a history line
function chat_system_history_line(message)

    local history_line = { time = chat_system_history_timestamp(), msg = message }
    return history_line

end

-- Generate timestamp
function chat_system_history_timestamp()

    return os.date("%x %X")

end