local Luan = require "luan:Luan.luan"
local error = Luan.error
local ipairs = Luan.ipairs or error()
local Number = require "luan:Number.luan"
local long = Number.long or error()
local Html = require "luan:Html.luan"
local html_encode = Html.encode or error()
local Db = require "site:/lib/Db.luan"
local Shared = require "site:/lib/Shared.luan"
local languages = Shared.languages or error()
local User = require "site:/lib/User.luan"
local get_user_by_id = User.get_by_id or error()


local Course = {}

local function from_doc(doc)
	doc.type == "course" or error "wrong type"
	return Course.new {
		id = doc.id
		user_id = doc.course_user_id
		language = doc.course_language
		updated = doc.course_updated
		name = doc.name
		ai_system_prompt = doc.ai_system_prompt
		ai_first_message = doc.ai_first_message
		tts_instructions = doc.tts_instructions
		has_ruby = doc.has_ruby == "true"
		description = doc.description or ""
		stt_prompt = doc.stt_prompt or ""
	}
end

local function to_doc(course)
	return {
		type = "course"
		id = course.id
		course_user_id = long(course.user_id)
 		course_language = course.language or error()
		course_updated = long(course.updated)
		name = course.name or error()
		ai_system_prompt = course.ai_system_prompt or error()
		ai_first_message = course.ai_first_message or error()
		tts_instructions = course.tts_instructions or error()
		has_ruby = course.has_ruby and "true" or nil
		description = course.description or error()
		stt_prompt = course.stt_prompt or error()
	}
end

function Course.new(course)

	function course.save()
		local doc = to_doc(course)
		Db.save(doc)
		course.id = doc.id
	end

	function course.delete()
		Db.delete("id:"..course.id)
	end

	function course.name_html()
		return html_encode(course.name)
	end

	function course.language_name()
		return languages[course.language]
	end

	function course.get_user()
		return get_user_by_id(course.user_id)
	end

	return course
end

function Course.search(query,sort,rows)
	rows = rows or 1000000
	local courses = {}
	local docs = Db.search(query,1,rows,{sort=sort})
	for _, doc in ipairs(docs) do
		courses[#courses+1] = from_doc(doc)
	end
	return courses
end

function Course.get_by_id(id)
	local doc = Db.get_document("id:"..id)
	return doc and doc.type=="course" and from_doc(doc) or nil
end

return Course