{-# LANGUAGE OverloadedStrings #-}
module Main where

import Test.Hspec
import Data.HashMap.Strict
import Data.Maybe (fromJust)
import Network.URI
import Data.Scientific (toRealFloat)

import Data.CSS.Syntax.Tokens
import Data.CSS.Syntax.StyleSheet (parse, StyleSheet(..), TrivialStyleSheet(..), scanAtRule, scanValue)
import Data.CSS.Syntax.Selector

import Data.CSS.Style.Common
import Data.CSS.Style.Selector.Index
import Data.CSS.Style.Selector.Interpret
import Data.CSS.Style

import Data.CSS.Preprocessor.Conditions
import Data.CSS.Preprocessor.Conditions.Expr (Datum(..), Op(..), parse', eval)

main :: IO ()
main = hspec spec

spec :: Spec
spec = do
    describe "Canary" $ do
        it "Test framework works" $ do
            True `shouldBe` True
    describe "Parsing" $ do
        it "Can scan @rules" $ do
            scanAtRule [Ident "utf-8", Semicolon, Ident "a"] `shouldBe` ([Ident "utf-8", Semicolon], [Ident "a"])
            scanAtRule [Ident "before", LeftCurlyBracket, Ident "inside", RightCurlyBracket, Ident "after"] `shouldBe` (
                [Ident "before", LeftCurlyBracket, Ident "inside", RightCurlyBracket],
                [Ident "after"])
        it "Ignores @rules" $ do
            parse emptyStyle "@encoding 'utf-8';" `shouldBe` emptyStyle
            parse emptyStyle "  @encoding 'utf-8';" `shouldBe` emptyStyle
            parse emptyStyle "@encoding 'utf-8';  " `shouldBe` emptyStyle
            parse emptyStyle "@media print { a:link {color: green;} }" `shouldBe` emptyStyle
            parse emptyStyle "  @media print { a:link {color: green;} }" `shouldBe` emptyStyle
            parse emptyStyle "@media print { a:link {color: green;} }  " `shouldBe` emptyStyle

            parse emptyStyle "@encoding 'utf-8'; a {color:green}" `shouldBe` linkStyle
            parse emptyStyle "a {color:green}@encoding 'utf-8';" `shouldBe` linkStyle
            parse emptyStyle "@media print{a{color:black;}}a {color:green}" `shouldBe` linkStyle
            parse emptyStyle "a {color:green} @media print {a{color:black;}}" `shouldBe` linkStyle
        it "Parses style rules" $ do
            -- Syntax examples from "Head First HTML & CSS with XHTML"
            parse emptyStyle "bedroom { drapes: blue; carpet: wool shag; }" `shouldBe` TrivialStyleSheet [
                StyleRule (Element [Tag "bedroom"]) [
                    ("drapes", [Ident "blue"]),
                    ("carpet", [Ident "wool", Ident "shag"])
                ] ""]
            parse emptyStyle "  bathroom{tile :1in white;drapes :pink}" `shouldBe` TrivialStyleSheet [
                StyleRule (Element [Tag "bathroom"]) [
                    ("tile", [Dimension "1" (NVInteger 1) "in", Ident "white"]),
                    ("drapes", [Ident "pink"])
                ] ""]
        it "Parses selectors" $ do
            parse emptyStyle ".class {}" `shouldBe` TrivialStyleSheet [
                    StyleRule (Element [Class "class"]) [] ""
                ]
            parse emptyStyle "*.class {}" `shouldBe` TrivialStyleSheet [
                    StyleRule (Element [Class "class"]) [] ""
                ]
            parse emptyStyle "#id {}" `shouldBe` TrivialStyleSheet [
                    StyleRule (Element [Id "id"]) [] ""
                ]
            parse emptyStyle "[attr] {}" `shouldBe` TrivialStyleSheet [
                    StyleRule (Element [Property "attr" Exists]) [] ""
                ]
            parse emptyStyle "a , b {}" `shouldBe` TrivialStyleSheet [
                    StyleRule (Element [Tag "b"]) [] "",
                    StyleRule (Element [Tag "a"]) [] ""
                ]
            parse emptyStyle "a b {}" `shouldBe` TrivialStyleSheet [
                    StyleRule (Descendant (Element [Tag "a"]) [Tag "b"]) [] ""
                ]
            parse emptyStyle "a > b {}" `shouldBe` TrivialStyleSheet [
                    StyleRule (Child (Element [Tag "a"]) [Tag "b"]) [] ""
                ]
            parse emptyStyle "a ~ b {}" `shouldBe` TrivialStyleSheet [
                    StyleRule (Sibling (Element [Tag "a"]) [Tag "b"]) [] ""
                ]
            parse emptyStyle "a + b {}" `shouldBe` TrivialStyleSheet [
                    StyleRule (Adjacent (Element [Tag "a"]) [Tag "b"]) [] ""
                ]
            parse emptyStyle "a::before {}"
                `shouldBe` TrivialStyleSheet [
                    StyleRule (Element [Tag "a"]) [] "before"
                ]
            parse emptyStyle "a:before {}"
                `shouldBe` TrivialStyleSheet [
                    StyleRule (Element [Tag "a", Psuedoclass "before" []]) [] ""
                ]
    describe "Style Index" $ do
        it "Retrieves appropriate styles" $ do
            let index = addStyleRule styleIndex 0 $ styleRule' sampleRule
            let element = ElementNode {
                name = "a",
                parent = Nothing,
                previous = Nothing,
                attributes = [
                    Attribute "class" "external",
                    Attribute "href" "https://adrian.geek.nz/",
                    Attribute "id" "mysite"
                ]
            }
            let element2 = ElementNode {
                name = "b",
                parent = Just element,
                previous = Just element, -- Invalid tree, oh well.
                attributes = []
            }
            rulesForElement index element `shouldBe` [sampleRule]
            rulesForElement index element2 `shouldBe` []

            let rule1 = StyleRule (Element [Class "external"]) [("color", [Ident "green"])] ""
            let index1 = addStyleRule styleIndex 0 $ styleRule' rule1
            rulesForElement index1 element `shouldBe` [rule1]
            rulesForElement index1 element2 `shouldBe` []

            let rule2 = StyleRule (Element [Id "mysite"]) [("color", [Ident "green"])] ""
            let index2 = addStyleRule styleIndex 0 $ styleRule' rule2
            rulesForElement index2 element `shouldBe` [rule2]
            rulesForElement index2 element2 `shouldBe` []

            let rule3 = StyleRule (Element [Property "href" $ Prefix "https://"]) [("color", [Ident "green"])] ""
            let index3 = addStyleRule styleIndex 0 $ styleRule' rule3
            rulesForElement index3 element `shouldBe` [rule3]
            rulesForElement index3 element2 `shouldBe` []
    describe "Selector Compiler" $ do
        it "Correctly evaluates selectors" $ do
            let parentEl = ElementNode {
                name = "a",
                parent = Nothing,
                previous = Nothing,
                attributes = [
                    Attribute "class" "external secure link",
                    Attribute "href" "https://adrian.geek.nz/index.html",
                    Attribute "id" "mysite",
                    Attribute "lang" "en-US"
                ]
            }
            let sibling = ElementNode {
                name = "img",
                parent = Just parentEl,
                previous = Nothing,
                attributes = []
            }
            let child = ElementNode {
                name = "b",
                parent = Just parentEl,
                previous = Just sibling,
                attributes = []
            }

            let selector1 = compile (Element [Tag "a"])
            selector1 parentEl `shouldBe` True
            selector1 sibling `shouldBe` False
            selector1 child `shouldBe` False

            let selector2 = compile (Element [Class "external"])
            selector2 parentEl `shouldBe` True
            selector2 sibling `shouldBe` False
            selector2 child `shouldBe` False

            let selector3 = compile (Element [Id "mysite"])
            selector3 parentEl `shouldBe` True
            selector3 sibling `shouldBe` False
            selector3 child `shouldBe` False

            let selector4 = compile (Element [Property "lang" Exists])
            selector4 parentEl `shouldBe` True
            selector4 sibling `shouldBe` False
            selector4 child `shouldBe` False

            let selector5 = compile (Element [Property "class" $ Include "secure"])
            selector5 parentEl `shouldBe` True
            selector5 sibling `shouldBe` False
            selector5 child `shouldBe` False

            let selector6 = compile (Element [Property "href" $ Prefix "https://"])
            selector6 parentEl `shouldBe` True
            selector6 sibling `shouldBe` False
            selector6 child `shouldBe` False

            let selector7 = compile (Element [Property "href" $ Suffix ".html"])
            selector7 parentEl `shouldBe` True
            selector7 sibling `shouldBe` False
            selector7 child `shouldBe` False

            let selector8 = compile (Element [Property "href" $ Substring ".geek.nz"])
            selector8 parentEl `shouldBe` True
            selector8 sibling `shouldBe` False
            selector8 child `shouldBe` False

            let selector9 = compile (Element [Property "lang" $ Dash "en"])
            selector9 parentEl `shouldBe` True
            selector9 sibling `shouldBe` False
            selector9 child `shouldBe` False

            let selectorA = compile (Element [Property "lang" $ Dash "en-US"])
            selectorA parentEl `shouldBe` True
            selectorA sibling `shouldBe` False
            selectorA child `shouldBe` False

            let selectorB = compile (Element [Property "lang" $ Dash "en-UK"])
            selectorB parentEl `shouldBe` False
            selectorB sibling `shouldBe` False
            selectorB child `shouldBe` False

            -- TODO These could be tested better.
            let selectorC = compile $ Child (Element [Tag "a"]) [Tag "b"]
            selectorC parentEl `shouldBe` False
            selectorC sibling `shouldBe` False
            selectorC child `shouldBe` True

            let selectorD = compile $ Descendant (Element [Tag "a"]) [Tag "b"]
            selectorD parentEl `shouldBe` False
            selectorD sibling `shouldBe` False
            selectorD child `shouldBe` True

            let selectorE = compile $ Sibling (Element [Tag "img"]) [Tag "b"]
            selectorE parentEl `shouldBe` False
            selectorE sibling `shouldBe` False
            selectorE child `shouldBe` True

            let selectorF = compile $ Adjacent (Element [Tag "img"]) [Tag "b"]
            selectorF parentEl `shouldBe` False
            selectorF sibling `shouldBe` False
            selectorF child `shouldBe` True

    describe "Style resolution" $ do
        it "respects selector specificity" $ do
            let el = ElementNode {
                name = "a",
                parent = Nothing,
                previous = Nothing,
                attributes = [Attribute "class" "link"]
            }
            let rules = parse queryable "a.link {color: green} a {color: red}"
            let VarParser _ (TrivialPropertyParser style) = cascade rules el [] temp::(VarParser TrivialPropertyParser)
            style ! "color" `shouldBe` [Ident "green"]
        it "respects syntax order" $ do
            let el = ElementNode {
                name = "a",
                parent = Nothing,
                previous = Nothing,
                attributes = [Attribute "class" "link"]
            }
            let rules = parse queryable "a {color: red; color: green}"
            let VarParser _ (TrivialPropertyParser style) = cascade rules el [] temp::(VarParser TrivialPropertyParser)
            style ! "color" `shouldBe` [Ident "green"]

            let rules2 = parse queryable "a {color: red} a {color: green}"
            let VarParser _ (TrivialPropertyParser style2) = cascade rules2 el [] temp::(VarParser TrivialPropertyParser)
            style2 ! "color" `shouldBe` [Ident "green"]
        it "respects stylesheet precedence" $ do
            let el = ElementNode {
                name = "a",
                parent = Nothing,
                previous = Nothing,
                attributes = [Attribute "class" "link"]
            }
            let rules = parse (queryable {priority = 1}) "a {color: green}"
            let rules2 = parse (rules {priority = 2}) "a {color: red}" :: QueryableStyleSheet (VarParser TrivialPropertyParser)
            let VarParser _ (TrivialPropertyParser style) = cascade rules2 el [] temp::(VarParser TrivialPropertyParser)
            style ! "color" `shouldBe` [Ident "green"]

            let el' = ElementNode {
                name = "a",
                parent = Nothing,
                previous = Nothing,
                attributes = [Attribute "class" "link"]
            }
            let rules' = parse (queryable {priority = 1}) "a {color: red}"
            let rules2' = parse (rules' {priority = 2}) "a {color: green !important}" :: QueryableStyleSheet (VarParser TrivialPropertyParser)
            let VarParser _ (TrivialPropertyParser style') = cascade rules2' el' [] temp::(VarParser TrivialPropertyParser)
            style' ! "color" `shouldBe` [Ident "green"]
        it "respects overrides" $ do
            let el = ElementNode {
                name = "a",
                parent = Nothing,
                previous = Nothing,
                attributes = [Attribute "class" "link"]
            }
            let rules = parse queryable "a {color: red;}"
            let VarParser _ (TrivialPropertyParser style) = cascade rules el [("color", [Ident "green"])] temp::(VarParser TrivialPropertyParser)
            style ! "color" `shouldBe` [Ident "green"]
    describe "Parser freezes" $ do
        it "does not regress" $ do
            parse emptyStyle "output: {content: 'Output'; pitch: high}"
                `shouldBe` TrivialStyleSheet [
                    StyleRule (Element [Tag "output"]) [] ""
                ] -- Turned out to just be incorrect parsing
            parse emptyStyle "input, output {content: attr(value)}"
                `shouldBe` TrivialStyleSheet [
                    StyleRule (Element [Tag "output"]) [
                        ("content", [Function "attr", Ident "value", RightParen])
                    ] "",
                    StyleRule (Element [Tag "input"]) [
                        ("content", [Function "attr", Ident "value", RightParen])
                    ] ""
                ]
        it "paren balancing" $ do
            scanValue [RightParen] `shouldBe` ([], [RightParen])
            scanValue [LeftParen] `shouldBe` ([LeftParen], [])
            scanValue [Function "fn", LeftParen] `shouldBe` ([Function "fn", LeftParen], [])
            scanValue [Function "fn", Ident "arg", LeftParen] `shouldBe`
                ([Function "fn", Ident "arg", LeftParen], [])

    describe "CSS Variables" $ do
        it "are captured" $ do
            let parser = temp :: VarParser TrivialPropertyParser
            vars parser `shouldBe` []
            let parser1 = setVars [("--var", [Ident "value"])] parser
            vars parser1 `shouldBe` [("--var", [Ident "value"])]
            let parser2 = fromJust $ longhand parser parser1 "property" [Function "var", Ident "--var", RightParen]
            vars parser2 `shouldBe` [("--var", [Ident "value"])]
            let VarParser _ (TrivialPropertyParser style) = parser2
            style ! "property" `shouldBe` [Ident "value"]

            let el = ElementNode {
                name = "a",
                parent = Nothing,
                previous = Nothing,
                attributes = []
            }
            let rules = parse queryable "a {--var: value}"
            let VarParser v _ = cascade rules el [] temp
            v `shouldBe` [("--var", [Ident "value"])]
        it "applies within element" $ do
            let el = ElementNode {
                name = "a",
                parent = Nothing,
                previous = Nothing,
                attributes = []
            }
            let rules = parse queryable "a {--link: #f00; color: var(--link)}"
            let VarParser vars (TrivialPropertyParser style) = cascade rules el [] temp
            style ! "color" `shouldBe` [Hash HId "f00"]
            style ! "--link" `shouldBe` [Hash HId "f00"]
            vars `shouldBe` [("--link", [Hash HId "f00"])]
        it "inherits" $ do
            let parent = ElementNode {
                name = "a",
                parent = Nothing,
                previous = Nothing,
                attributes = []
            }
            let el = ElementNode {
                name = "b",
                parent = Just parent,
                previous = Nothing,
                attributes = []
            }
            let rules = parse queryable "a {--link: #f00} b {color: var(--link)}"
            let VarParser vars (TrivialPropertyParser style) = cascade rules el [] $ cascade rules parent [] temp
            vars `shouldBe` [("--link", [Hash HId "f00"])]
            style ! "color" `shouldBe` [Hash HId "f00"]
    describe "Conditional @rules" $ do
        it "handles normal rules" $ do
            let TrivialStyleSheet styles = resolve' $ parse conditional "a {color: green}"
            styles `shouldBe` [StyleRule (Element [Tag "a"]) [("color", [Ident "green"])] ""]

            let TrivialStyleSheet styles = resolve' $ parse conditional "@rule; a {color: green}"
            styles `shouldBe` [StyleRule (Element [Tag "a"]) [("color", [Ident "green"])] ""]

            let TrivialStyleSheet styles = resolve' $ parse conditional "a {color: green} @rule;"
            styles `shouldBe` [StyleRule (Element [Tag "a"]) [("color", [Ident "green"])] ""]

            let TrivialStyleSheet styles = resolve' $ parse conditional "a {color: green} @font {}"
            styles `shouldBe` [StyleRule (Element [Tag "a"]) [("color", [Ident "green"])] ""]

            let TrivialStyleSheet styles = resolve' $ parse conditional "@font {} a {color: green}"
            styles `shouldBe` [StyleRule (Element [Tag "a"]) [("color", [Ident "green"])] ""]
        it "handles @document" $ do
            let TrivialStyleSheet styles = resolve' $ parse conditional "@document url(about:blank) { a {color: green} }"
            styles `shouldBe` [StyleRule (Element []) [] "", StyleRule (Element [Tag "a"]) [("color", [Ident "green"])] ""]
            let TrivialStyleSheet styles = resolve' $ parse conditional "@document url(about:credits) { a {color: red} }"
            styles `shouldBe` []
            let TrivialStyleSheet styles = resolve' $ parse conditional "@document url-prefix('about:') { a {color: green} }"
            styles `shouldBe` [StyleRule (Element []) [] "", StyleRule (Element [Tag "a"]) [("color", [Ident "green"])] ""]
            let TrivialStyleSheet styles = resolve' $ parse conditional "@document url-prefix('https:') { a {color: red} }"
            styles `shouldBe` []
            let TrivialStyleSheet styles = resolve' $ parse conditional "@document media-document('test') { a {color: green} }"
            styles `shouldBe` [StyleRule (Element []) [] "", StyleRule (Element [Tag "a"]) [("color", [Ident "green"])] ""]
            let TrivialStyleSheet styles = resolve' $ parse conditional "@document media-document('other') { a {color: red} }"
            styles `shouldBe` []
        it "handles @media" $ do
            let TrivialStyleSheet styles = resolve' $ parse conditional "@media test { a {color: green} }"
            styles `shouldBe` [StyleRule (Element []) [] "", StyleRule (Element [Tag "a"]) [("color", [Ident "green"])] ""]
            let TrivialStyleSheet styles = resolve' $ parse conditional "@media screen { a {color: red} }"
            styles `shouldBe` []

            let TrivialStyleSheet styles = resolve' $ parse conditional "@media test or screen { a {color: green} }"
            styles `shouldBe` [StyleRule (Element []) [] "", StyleRule (Element [Tag "a"]) [("color", [Ident "green"])] ""]
            let TrivialStyleSheet styles = resolve' $ parse conditional "@media test or test {a {color: green} }"
            styles `shouldBe` [StyleRule (Element []) [] "", StyleRule (Element [Tag "a"]) [("color", [Ident "green"])] ""]
            let TrivialStyleSheet styles = resolve' $ parse conditional "@media screen or screen {a {color: red} }"
            styles `shouldBe` []
            let TrivialStyleSheet styles = resolve' $ parse conditional "@media screen or test {a {color: green} }"
            styles `shouldBe` [StyleRule (Element []) [] "", StyleRule (Element [Tag "a"]) [("color", [Ident "green"])] ""]

            let TrivialStyleSheet styles = resolve' $ parse conditional "@media test and screen { a {color: red} }"
            styles `shouldBe` []
            let TrivialStyleSheet styles = resolve' $ parse conditional "@media test and test { a {color: green} }"
            styles `shouldBe` [StyleRule (Element []) [] "", StyleRule (Element [Tag "a"]) [("color", [Ident "green"])] ""]
            let TrivialStyleSheet styles = resolve' $ parse conditional "@media screen and screen { a {color: red} }"
            styles `shouldBe` []
            let TrivialStyleSheet styles = resolve' $ parse conditional "@media screen and test {a {color: red} }"
            styles `shouldBe` []

            let TrivialStyleSheet styles = resolve' $ parse conditional "@media 2 < 3 { a {color: green} }"
            styles `shouldBe` [StyleRule (Element []) [] "", StyleRule (Element [Tag "a"]) [("color", [Ident "green"])] ""]
            let TrivialStyleSheet styles = resolve' $ parse conditional "@media 2 < 2 { a {color: red} }"
            styles `shouldBe` []
            let TrivialStyleSheet styles = resolve' $ parse conditional "@media 2 < 1 { a {color: red} }"
            styles `shouldBe` []
        it "handles @import" $ do
            let styles = parse conditional "@import url(about:style.css);"
            extractImports' styles `shouldBe` [URI "about:" Nothing "style.css" "" ""]
            let styles = parse conditional "@import 'about:style.css';"
            extractImports' styles `shouldBe` [URI "about:" Nothing "style.css" "" ""]

            let styles = parse conditional "@import url(about:style.css) test;"
            extractImports' styles `shouldBe` [URI "about:" Nothing "style.css" "" ""]
            let styles = parse conditional "@import url(about:style.css) screen;"
            extractImports' styles `shouldBe` []
        -- TODO @supports is harder to test

styleIndex :: StyleIndex
styleIndex = new
queryable :: QueryableStyleSheet (VarParser TrivialPropertyParser)
queryable = queryableStyleSheet
emptyStyle :: TrivialStyleSheet
emptyStyle = TrivialStyleSheet []
conditional :: ConditionalStyles TrivialPropertyParser
conditional = conditionalStyles (fromJust $ parseURI "about:blank") "test"
linkStyle :: TrivialStyleSheet
linkStyle = TrivialStyleSheet [sampleRule]
sampleRule :: StyleRule
sampleRule = StyleRule (Element [Tag "a"]) [("color", [Ident "green"])] ""
resolve' = resolve (\var -> B (var == "test")) evalToken emptyStyle
    where
        evalToken (Number _ (NVInteger x)) = N $ fromInteger x
        evalToken (Number _ (NVNumber x)) = N $ toRealFloat x
        evalToken _ = B False
extractImports' = extractImports (\var -> B (var == "test")) evalToken
    where
        evalToken (Number _ (NVInteger x)) = N $ fromInteger x
        evalToken (Number _ (NVNumber x)) = N $ toRealFloat x
        evalToken _ = B False