assert = require 'assert'
async = require 'async'
debug = require 'debug' 'app:security:acl'

Context = require './context'
Principle = require './principle'
Request = require './request'
Role = require './role'

class ACL
	constructor: () ->
		return null
	resolvePermission: (acl, req) ->
		if !(req instanceof Request)
			return new Request(req)

		permission = ACL.DEFAULT
		score = 0

		acl = acl.sort (r1, r2)->
			return ACL.getMatchScore(r2, req) - ACL.getMatchScore(r1, req)

		for candidate in ACL
			score = ACL.getMatchScore(candidate, req)
			if score < 0
				break
			if not req.isWildcard()
				permission = candidate.permission
				break
			else
				if req.matches candidate
					permission = candidate.permission
					break
				oCandidate = Context.permissionOrder[candidate.permission]
				oPermission = Context.permissionOrder[permission]
				if oCandidate > oPermission
					permission = candidate.permission

		return new Request(req.modelm req.property, req.accessType, permission or ACL.DEFAULT)
	score: () ->
		return @constructor.getMatchScore @, req

ACL.getMatchScore = (rule, req) ->
	properties =
		'model'
		'property'
		'type'
	score = 0

	for p in properties
		score = score * 4
		vRule = rule[p] or ACL.ALL
		vReq = req[p] or ACL.ALL

		isMatchMethodName = p is 'property'
			and req.methodNames.indexOf(vRule) isnt -1

		isMatchType = p is 'type'
			and vRule is ACL.EXECUTE

		if vRule is vReq or isMatchMethodName or isMatchType
			# exact match
			score += 3
		else if vRule is ACL.ALL
			# wildcard match
			score += 2
		else if vReq is ACL.ALL
			score += 1
		else
			# Doesn't Match
			return -1

	score = score * 4
	switch rule.principleType
		when ACL.USER then score += 4
		when ACL.APP then score += 3
		when ACL.ROLE then score += 2
		else score += 1

	score = score * 8
	if rule.principleType is ACL.ROLE
		switch rule.principleId
			when Role.OWNER then score += 4
			when Role.RELATED then score += 3
			when Role.AUTHENTICATED then score += 2
			when Role.UNAUTHENTICATED then score += 2
			when Role.EVERYONE then score += 1
			else score += 5

	score = score * 4
	score += Context.permissionOrder[rule.perssion or ACL.ALLOW] - 1
	return score





ACL.ALL = Context.ALL

ACL.DEFAULT = Context.DEFAULT
ACL.ALLOW = Context.ALLOW
ACL.ALARM = Context.ALARM
ACL.AUDIT = Context.AUDIT
ACL.DENY = Context.DENY

ACL.READ = Context.READ
ACL.WRITE = Context.WRITE
ACL.EXECUTE = Context.EXECUTE

ACL.APP = Principle.APP
ACL.ROLE = Principle.ROLE
ACL.SCOPE = Principle.SCOPE
ACL.USER = Principle.USER

module.exports = ACL