---[[
LuCI http protocol class.

This class contains several functions useful for http message- and content
decoding and to retrive form data from raw http messages.
]]
module "luci.http.protocol"

---[[
Extract and split urlencoded data pairs, separated bei either "&" or ";"

from given url or string. Returns a table with urldecoded values.
Simple parameters are stored as string values associated with the parameter
name within the table. Parameters with multiple values are stored as array
containing the corresponding values.
@class function
@name urldecode_params
@param url	The url or string which contains x-www-urlencoded form data
@param tbl	Use the given table for storing values (optional)
@return		Table containing the urldecoded parameters
@see			urlencode_params
]]

---[[
Encode each key-value-pair in given table to x-www-urlencoded format,

separated by "&". Tables are encoded as parameters with multiple values by
repeating the parameter name with each value.
@class function
@name urlencode_params
@param tbl	Table with the values
@return		String containing encoded values
@see			urldecode_params
]]

---[[
Creates a ltn12 source from the given socket. The source will return it's

data line by line with the trailing \r\n stripped of.
@class function
@name header_source
@param sock	Readable network socket
@return		Ltn12 source function
]]

---[[
Decode a mime encoded http message body with multipart/form-data

Content-Type. Stores all extracted data associated with its parameter name
in the params table within the given message object. Multiple parameter
values are stored as tables, ordinary ones as strings.
If an optional file callback function is given then it is feeded with the
file contents chunk by chunk and only the extracted file name is stored
within the params table. The callback function will be called subsequently
with three arguments:
 o Table containing decoded (name, file) and raw (headers) mime header data
 o String value containing a chunk of the file data
 o Boolean which indicates wheather the current chunk is the last one (eof)
@class function
@name mimedecode_message_body
@param src		Ltn12 source function
@param msg		HTTP message object
@param filecb	File callback function (optional)
@return			Value indicating successful operation (not nil means "ok")
@return			String containing the error if unsuccessful
@see				parse_message_header
]]

---[[
Decode an urlencoded http message body with application/x-www-urlencoded

Content-Type. Stores all extracted data associated with its parameter name
in the params table within the given message object. Multiple parameter
values are stored as tables, ordinary ones as strings.
@class function
@name urldecode_message_body
@param src	Ltn12 source function
@param msg	HTTP message object
@return		Value indicating successful operation (not nil means "ok")
@return		String containing the error if unsuccessful
@see			parse_message_header
]]

---[[
Try to extract an http message header including information like protocol

version, message headers and resulting CGI environment variables from the
given ltn12 source.
@class function
@name parse_message_header
@param src	Ltn12 source function
@return		HTTP message object
@see			parse_message_body
]]

---[[
Try to extract and decode a http message body from the given ltn12 source.

This function will examine the Content-Type within the given message object
to select the appropriate content decoder.
Currently the application/x-www-urlencoded and application/form-data
mime types are supported. If the encountered content encoding can't be
handled then the whole message body will be stored unaltered as "content"
property within the given message object.
@class function
@name parse_message_body
@param src		Ltn12 source function
@param msg		HTTP message object
@param filecb	File data callback (optional, see mimedecode_message_body())
@return			Value indicating successful operation (not nil means "ok")
@return			String containing the error if unsuccessful
@see				parse_message_header
]]

---[[
Table containing human readable messages for several http status codes.

@class table
]]