Files
swiftpm-stencil/Stencil/TemplateLoader/Inheritence.swift
2015-06-29 18:36:27 -07:00

125 lines
3.2 KiB
Swift

import Foundation
class BlockContext {
class var contextKey:String { return "block_context" }
var blocks:[String:BlockNode]
init(blocks:[String:BlockNode]) {
self.blocks = blocks
}
func pop(blockName:String) -> BlockNode? {
return blocks.removeValueForKey(blockName)
}
}
func any<Element>(elements:[Element], closure:(Element -> Bool)) -> Element? {
for element in elements {
if closure(element) {
return element
}
}
return nil
}
class ExtendsNode : Node {
let templateName:String
let blocks:[String:BlockNode]
class func parse(parser:TokenParser, token:Token) -> TokenParser.Result {
let bits = token.contents.componentsSeparatedByString("\"")
if bits.count != 3 {
return .Error(error:NodeError(token: token, message: "Tag takes one argument, the template file to be extended"))
}
switch parser.parse() {
case .Success(let nodes):
if (any(nodes) { ($0 as? ExtendsNode) != nil }) != nil {
return .Error(error:"'extends' cannot appear more than once in the same template")
}
let blockNodes = filter(nodes) { node in node is BlockNode }
let nodes = reduce(blockNodes, [String:BlockNode](), { (accumulator, node:Node) -> [String:BlockNode] in
let node = (node as! BlockNode)
var dict = accumulator
dict[node.name] = node
return dict
})
return .Success(node:ExtendsNode(templateName: bits[1], blocks: nodes))
case .Error(let error):
return .Error(error:error)
}
}
init(templateName:String, blocks:[String:BlockNode]) {
self.templateName = templateName
self.blocks = blocks
}
func render(context: Context) -> Result {
if let loader = context["loader"] as? TemplateLoader {
if let template = loader.loadTemplate(templateName) {
let blockContext = BlockContext(blocks: blocks)
context.push([BlockContext.contextKey: blockContext])
let result = template.render(context)
context.pop()
return result
}
let paths:String = join(", ", loader.paths.map { path in
return path.description
})
let error = "Template '\(templateName)' not found in \(paths)"
return .Error(error)
}
let error = "Template loader not in context"
return .Error(error)
}
}
class BlockNode : Node {
let name:String
let nodes:[Node]
class func parse(parser:TokenParser, token:Token) -> TokenParser.Result {
let bits = token.components()
if bits.count != 2 {
return .Error(error:NodeError(token: token, message: "Tag takes one argument, the template file to be included"))
}
let blockName = bits[1]
var nodes = [Node]()
switch parser.parse(until(["endblock"])) {
case .Success(let blockNodes):
nodes = blockNodes
case .Error(let error):
return .Error(error: error)
}
return .Success(node:BlockNode(name:blockName, nodes:nodes))
}
init(name:String, nodes:[Node]) {
self.name = name
self.nodes = nodes
}
func render(context: Context) -> Result {
if let blockContext = context[BlockContext.contextKey] as? BlockContext {
if let node = blockContext.pop(name) {
return node.render(context)
}
}
return renderNodes(nodes, context)
}
}