(ns pixie.ast-output

(:require [pixie.ast.internal :as iast]

[pixie.ast :as ast]))

(defprotocol ToNativeAST

(-to-ast [this]))

(defn meta-ast [ast]

(let [{:keys [line file line-number column-number] :as m} (or (meta (:form ast))

(:meta (:env ast)))

line (if (string? line)

line

(apply str @line))]

(iast/->Meta (or line

"<unknown>")

(or file

"<unknown>")

(or line-number -1)

(or column-number 1))))

(defn to-ast [this]

(-to-ast (simplify this)))

(extend-protocol ToNativeAST

ast/If

(-to-ast [{:keys [test then else] :as ast}]

(iast/->If (to-ast test)

(to-ast then)

(to-ast else)

(meta-ast ast)))

ast/Let

(-to-ast [{:keys [bindings body] :as ast}]

(iast/->Let (apply array (map #(keyword (name (:name %)))

bindings))

(apply array (map #(to-ast (:value %))

bindings))

(to-ast body)

(meta-ast ast)))

ast/Do

(-to-ast [{:keys [statements ret] :as ast}]

(let [args-array (make-array (inc (count statements)))]

(dotimes [idx (count statements)]

(aset args-array idx

(to-ast (nth statements idx))))

(aset args-array (count statements)

(to-ast ret))

(iast/->Do args-array

(meta-ast ast))))

ast/LetBinding

(-to-ast

[{:keys [name] :as ast}]

(iast/->Lookup (keyword (pixie.stdlib/name name))

(meta-ast ast)))

ast/Const

(-to-ast [{:keys [form] :as ast}]

(iast/->Const form (meta-ast ast)))

ast/Invoke

(-to-ast [{:keys [args env] :as ast}]

(let [args-array (make-array (count args))]

(dotimes [idx (count args)]

(aset args-array idx

(to-ast (nth args idx))))

(iast/->Invoke args-array

(meta-ast ast))))

ast/Recur

(-to-ast [{:keys [args env] :as ast}]

(let [args-array (make-array (count args))]

(dotimes [idx (count args)]

(aset args-array idx

(to-ast (nth args idx))))

(iast/->Recur args-array

(meta-ast ast))))

ast/Var

(-to-ast [{:keys [ns var-name] :as ast}]

(iast/->VDeref (name ns)

var-name

(meta-ast ast)))

ast/VarConst

(-to-ast [{:keys [ns name env] :as ast}]

(iast/->VarConst ns

name

(meta-ast ast)))

ast/FnBody

(-to-ast [{:keys [name args body] :as ast}]

(iast/->Fn (keyword (pixie.stdlib/name name))

(to-array (map (fn [x]

(keyword (pixie.stdlib/name x)))

args))

(to-ast body)

(meta-ast ast)))

ast/Binding

(-to-ast [{:keys [name] :as ast}]

(iast/->Lookup (keyword (pixie.stdlib/name name))

(meta-ast ast)))

Object

(-to-ast [this]

(println "Encoding" this "of type" (type this))

(throw [:pixie.stdlib/IllegalArgumentException

(str "Can't encode " this)])))

(defn simplify [ast]

(let [simplified (ast/simplify-ast ast)]

(if (identical? simplified ast)

ast

(simplify simplified))))