{-# LANGUAGE DataKinds #-}
{-# LANGUAGE OverloadedStrings #-}
{-# LANGUAGE TypeOperators #-}
{-# LANGUAGE NoImplicitPrelude #-}

-- | Web server for Ava trace viewer.
--
-- Serves the trace viewer UI for debugging tool executions.
--
-- : out omni-ava-web
-- : dep warp
-- : dep wai
-- : dep servant-server
-- : dep servant-lucid
-- : dep lucid
-- : dep http-types
-- : dep aeson
-- : dep aeson-pretty
-- : dep text
-- : dep bytestring
-- : dep sqlite-simple
module Omni.Ava.Web
  ( startWebServer,
    app,
    defaultPort,
    main,
  )
where

import Alpha
import qualified Data.Aeson as Aeson
import qualified Data.Aeson.Encode.Pretty as AesonPretty
import qualified Data.ByteString.Lazy as BL
import qualified Data.Text as Text
import qualified Data.Text.Encoding as TE
import qualified Database.SQLite.Simple as SQL
import qualified Lucid
import qualified Network.Wai.Handler.Warp as Warp
import qualified Omni.Ava.Trace as Trace
import Servant
import qualified Servant.HTML.Lucid as Lucid

main :: IO ()
main = putText "Use Omni.Ava for the main entry point"

defaultPort :: Int
defaultPort = 8079

startWebServer :: Int -> FilePath -> IO ()
startWebServer port dbPath = do
  putText <| "Starting Ava web server on port " <> tshow port
  SQL.withConnection dbPath Trace.initTraceDb
  Warp.run port (app dbPath)

type API =
  "trace" :> Capture "id" Text :> Get '[Lucid.HTML] TracePage
    :<|> "api" :> "trace" :> Capture "id" Text :> Get '[JSON] Aeson.Value
    :<|> "health" :> Get '[PlainText] Text

api :: Proxy API
api = Proxy

app :: FilePath -> Application
app dbPath = serve api (server dbPath)

server :: FilePath -> Server API
server dbPath =
  tracePageHandler dbPath
    :<|> traceJsonHandler dbPath
    :<|> healthHandler

healthHandler :: Servant.Handler Text
healthHandler = pure "ok"

tracePageHandler :: FilePath -> Text -> Servant.Handler TracePage
tracePageHandler dbPath tid = do
  maybeRec <- liftIO <| SQL.withConnection dbPath <| \conn -> Trace.getTrace conn tid
  case maybeRec of
    Nothing -> throwError err404
    Just rec -> pure (TracePage rec)

traceJsonHandler :: FilePath -> Text -> Servant.Handler Aeson.Value
traceJsonHandler dbPath tid = do
  maybeRec <- liftIO <| SQL.withConnection dbPath <| \conn -> Trace.getTrace conn tid
  case maybeRec of
    Nothing -> throwError err404
    Just rec -> pure (Aeson.toJSON rec)

-- | Wrapper for trace page rendering
newtype TracePage = TracePage Trace.TraceRecord

instance Lucid.ToHtml TracePage where
  toHtmlRaw = Lucid.toHtml
  toHtml (TracePage rec) =
    Lucid.doctypehtml_ <| do
      Lucid.head_ <| do
        Lucid.meta_ [Lucid.charset_ "utf-8"]
        Lucid.meta_ [Lucid.name_ "viewport", Lucid.content_ "width=device-width, initial-scale=1"]
        Lucid.title_ <| Lucid.toHtml ("Trace: " <> Trace.trcToolName rec)
        Lucid.style_ traceStyles
      Lucid.body_ <| do
        Lucid.h1_ <| Lucid.toHtml (Trace.trcToolName rec)
        Lucid.p_ [Lucid.class_ "meta"] <| do
          Lucid.toHtml (Trace.trcCreatedAt rec)
          " · "
          Lucid.toHtml (tshow (Trace.trcDurationMs rec) <> "ms")

        Lucid.div_ [Lucid.class_ "section", Lucid.id_ "input-section"] <| do
          Lucid.div_ [Lucid.class_ "section-header"] <| do
            "Input"
            Lucid.button_ [Lucid.class_ "copy-btn", Lucid.data_ "target" "input-content"] "Copy"
          Lucid.div_ [Lucid.class_ "section-content", Lucid.id_ "input-content"]
            <| Lucid.pre_
            <| Lucid.toHtml (prettyJson (Trace.trcInput rec))

        Lucid.div_ [Lucid.class_ "section", Lucid.id_ "output-section"] <| do
          Lucid.div_ [Lucid.class_ "section-header"] <| do
            "Output"
            Lucid.button_ [Lucid.class_ "copy-btn", Lucid.data_ "target" "output-content"] "Copy"
          Lucid.div_ [Lucid.class_ "section-content", Lucid.id_ "output-content"]
            <| Lucid.pre_
            <| Lucid.toHtml (prettyJson (Trace.trcOutput rec))

        Lucid.p_ [Lucid.class_ "footer"] <| Lucid.toHtml ("Trace ID: " <> Trace.trcId rec)

        Lucid.script_ traceScript

traceStyles :: Text
traceStyles =
  Text.unlines
    [ ":root { --bg: #1a1a2e; --fg: #eee; --accent: #4a9eff; --code-bg: #0d0d1a; }",
      "@media (prefers-color-scheme: light) {",
      "  :root { --bg: #fff; --fg: #222; --accent: #0066cc; --code-bg: #f5f5f5; }",
      "}",
      "* { box-sizing: border-box; }",
      "body { font-family: system-ui, sans-serif; background: var(--bg); color: var(--fg); padding: 1rem; margin: 0; max-width: 100%; }",
      "h1 { font-size: 1.25rem; margin: 0 0 0.5rem; }",
      ".meta { font-size: 0.875rem; opacity: 0.7; margin-bottom: 1rem; }",
      ".section { margin: 1rem 0; border: 1px solid var(--accent); border-radius: 8px; overflow: hidden; }",
      ".section-header { padding: 0.75rem 1rem; cursor: pointer; display: flex; justify-content: space-between; align-items: center; background: var(--code-bg); }",
      ".section-header::before { content: '▼'; margin-right: 0.5rem; transition: transform 0.2s; }",
      ".section.collapsed .section-header::before { transform: rotate(-90deg); }",
      ".section-content { padding: 1rem; display: block; overflow-x: auto; background: var(--code-bg); }",
      ".section.collapsed .section-content { display: none; }",
      "pre { margin: 0; white-space: pre-wrap; word-break: break-word; font-size: 0.875rem; font-family: ui-monospace, monospace; }",
      ".copy-btn { background: var(--accent); color: white; border: none; padding: 0.25rem 0.5rem; border-radius: 4px; cursor: pointer; font-size: 0.75rem; }",
      ".copy-btn:hover { opacity: 0.8; }",
      ".footer { font-size: 0.75rem; opacity: 0.5; margin-top: 2rem; text-align: center; }"
    ]

traceScript :: Text
traceScript =
  Text.unlines
    [ "document.querySelectorAll('.section-header').forEach(header => {",
      "  header.addEventListener('click', (e) => {",
      "    if (e.target.classList.contains('copy-btn')) return;",
      "    header.parentElement.classList.toggle('collapsed');",
      "  });",
      "});",
      "",
      "document.querySelectorAll('.copy-btn').forEach(btn => {",
      "  btn.addEventListener('click', () => {",
      "    const targetId = btn.getAttribute('data-target');",
      "    const text = document.getElementById(targetId).querySelector('pre').textContent;",
      "    navigator.clipboard.writeText(text).then(() => {",
      "      const orig = btn.textContent;",
      "      btn.textContent = 'Copied!';",
      "      setTimeout(() => btn.textContent = orig, 1500);",
      "    });",
      "  });",
      "});"
    ]

prettyJson :: Text -> Text
prettyJson t =
  case Aeson.decode (BL.fromStrict (TE.encodeUtf8 t)) :: Maybe Aeson.Value of
    Nothing -> t
    Just v -> TE.decodeUtf8 (BL.toStrict (AesonPretty.encodePretty v))