From c1841eb88a4147a7f6bec9598d9c90583841e2e9 Mon Sep 17 00:00:00 2001
From: Tigor Hutasuhut <tigor.hutasuhut@gmail.com>
Date: Mon, 8 Apr 2024 21:50:52 +0700
Subject: [PATCH] views: added simple home view with head component

---
 .air.toml                          |  2 +-
 cli/serve.go                       |  2 +
 config/default.go                  |  1 +
 main.go                            | 13 ++++++
 server/routes/api/api.go           |  2 +
 server/routes/middleware/logger.go | 25 +++++++++++
 server/routes/www/home.go          |  3 +-
 server/routes/www/hot_reload.go    | 68 ++++++++++++++++++++++++++++++
 server/routes/www/www.go           | 29 ++++++++++++-
 views/components/head.templ        | 17 ++++++++
 views/context.go                   | 19 +++++++++
 views/homeview/homeview.templ      | 10 ++++-
 12 files changed, 186 insertions(+), 5 deletions(-)
 create mode 100644 server/routes/www/hot_reload.go
 create mode 100644 views/components/head.templ
 create mode 100644 views/context.go

diff --git a/.air.toml b/.air.toml
index 50f4c85..ca4ce5d 100644
--- a/.air.toml
+++ b/.air.toml
@@ -23,7 +23,7 @@ poll_interval = 0
 post_cmd = []
 pre_cmd = [
     "mkdir -p public",
-    "tailwindcss -i views/styles.css -o public/style.css",
+    "tailwindcss -i views/style.css -o public/style.css",
     "templ generate",
     "sqlc generate",
 ]
diff --git a/cli/serve.go b/cli/serve.go
index 9266b8f..21fc466 100644
--- a/cli/serve.go
+++ b/cli/serve.go
@@ -28,10 +28,12 @@ var serveCmd = &cobra.Command{
 
 		api := &api.API{
 			Subreddits: subreddits,
+			Config:     cfg,
 		}
 
 		www := &www.WWW{
 			Subreddits: subreddits,
+			Config:     cfg,
 		}
 		server := server.New(cfg, api, www)
 
diff --git a/config/default.go b/config/default.go
index 5b8896a..dc22f96 100644
--- a/config/default.go
+++ b/config/default.go
@@ -14,4 +14,5 @@ var DefaultConfig = map[string]any{
 	"http.port":             "8080",
 	"http.host":             "0.0.0.0",
 	"http.shutdown_timeout": "5s",
+	"http.hotreload":        false,
 }
diff --git a/main.go b/main.go
index ea67d7e..bd09360 100644
--- a/main.go
+++ b/main.go
@@ -3,17 +3,30 @@ package main
 import (
 	"context"
 	"embed"
+	"errors"
+	"io/fs"
 	"os"
 
+	"github.com/joho/godotenv"
 	"github.com/tigorlazuardi/redmage/cli"
 	"github.com/tigorlazuardi/redmage/db"
+	"github.com/tigorlazuardi/redmage/server/routes/www"
 )
 
 //go:embed db/migrations/*.sql
 var Migrations embed.FS
 
+//go:embed public/*
+var PublicFS embed.FS
+
 func main() {
+	_ = godotenv.Load()
 	db.Migrations = Migrations
+	var err error
+	www.PublicFS, err = fs.Sub(PublicFS, "public")
+	if err != nil {
+		panic(errors.New("failed to create sub filesystem"))
+	}
 	if err := cli.RootCmd.ExecuteContext(context.Background()); err != nil {
 		os.Exit(1)
 	}
diff --git a/server/routes/api/api.go b/server/routes/api/api.go
index 3b58842..66921a7 100644
--- a/server/routes/api/api.go
+++ b/server/routes/api/api.go
@@ -3,12 +3,14 @@ package api
 import (
 	"github.com/go-chi/chi/v5"
 	chimiddleware "github.com/go-chi/chi/v5/middleware"
+	"github.com/tigorlazuardi/redmage/config"
 	"github.com/tigorlazuardi/redmage/db/queries/subreddits"
 	"github.com/tigorlazuardi/redmage/server/routes/middleware"
 )
 
 type API struct {
 	Subreddits *subreddits.Queries
+	Config     *config.Config
 }
 
 func (api *API) Register(router chi.Router) {
diff --git a/server/routes/middleware/logger.go b/server/routes/middleware/logger.go
index ce4fb8b..0d29557 100644
--- a/server/routes/middleware/logger.go
+++ b/server/routes/middleware/logger.go
@@ -77,3 +77,28 @@ func formatDuration(dur time.Duration) string {
 
 	return fmt.Sprintf("%.3fms", nanosecs/float64(time.Millisecond))
 }
+
+type ChiSimpleLogger struct{}
+
+func (ChiSimpleLogger) NewLogEntry(r *http.Request) chimiddleware.LogEntry {
+	return &ChiSimpleEntry{request: r}
+}
+
+type ChiSimpleEntry struct {
+	request *http.Request
+}
+
+func (ch *ChiSimpleEntry) Write(status int, bytes int, header http.Header, elapsed time.Duration, extra interface{}) {
+	elapsedStr := formatDuration(elapsed)
+	message := fmt.Sprintf("%s %s %d %s", ch.request.Method, ch.request.URL, status, elapsedStr)
+
+	level := slog.LevelInfo
+	if status >= 400 {
+		level = slog.LevelError
+	}
+	log.New(ch.request.Context()).Level(level).Log(message)
+}
+
+func (ch *ChiSimpleEntry) Panic(v interface{}, stack []byte) {
+	(&ChiEntry{ch.request}).Panic(v, stack)
+}
diff --git a/server/routes/www/home.go b/server/routes/www/home.go
index a0b48f6..d6379b3 100644
--- a/server/routes/www/home.go
+++ b/server/routes/www/home.go
@@ -3,9 +3,10 @@ package www
 import (
 	"net/http"
 
+	"github.com/tigorlazuardi/redmage/views"
 	"github.com/tigorlazuardi/redmage/views/homeview"
 )
 
 func (www *WWW) Home(rw http.ResponseWriter, r *http.Request) {
-	_ = homeview.Home().Render(r.Context(), rw)
+	_ = homeview.Home(views.NewContext(www.Config, r)).Render(r.Context(), rw)
 }
diff --git a/server/routes/www/hot_reload.go b/server/routes/www/hot_reload.go
new file mode 100644
index 0000000..c671c07
--- /dev/null
+++ b/server/routes/www/hot_reload.go
@@ -0,0 +1,68 @@
+package www
+
+import (
+	"errors"
+	"io"
+	"net/http"
+	"sync"
+
+	"github.com/tigorlazuardi/redmage/pkg/log"
+)
+
+func (www *WWW) CreateHotReloadRoute() http.HandlerFunc {
+	var mu sync.Mutex
+	knownClients := make(map[string]chan struct{})
+	firstTime := make(chan struct{}, 1)
+	firstTime <- struct{}{}
+	return func(w http.ResponseWriter, r *http.Request) {
+		id := r.URL.Query().Get("id")
+		var ch chan struct{}
+		if oldChannel, known := knownClients[id]; known {
+			ch = oldChannel
+		} else {
+			ch = make(chan struct{}, 1)
+			ch <- struct{}{}
+			knownClients[id] = ch
+		}
+
+		w.Header().Set("Content-Type", "text/event-stream")
+		w.Header().Set("Cache-Control", "no-cache")
+		w.Header().Set("Connection", "keep-alive")
+		w.WriteHeader(200)
+		for {
+			select {
+			case <-r.Context().Done():
+				return
+			case <-firstTime:
+				// dispose own's channel buffer to prevent deadlock.
+				// because it will be filled with new signal below.
+				if len(ch) > 0 {
+					<-ch
+				}
+				// broadcast to all connected clients
+				// that hot reload is triggered.
+				//
+				// The sender only send one signal,
+				// and the receiver is only one, and chosen at random, so
+				// we have to propagate the signal to all
+				// connected clients.
+				mu.Lock()
+				for _, ch := range knownClients {
+					ch <- struct{}{}
+				}
+				mu.Unlock()
+			case <-ch:
+				_, err := io.WriteString(w, "data: Hot reload triggered\n\n")
+				if err != nil {
+					log.New(r.Context()).Err(err).Error("failed to send hot reload trigger", "channel_id", id)
+					return
+				}
+				if w, ok := w.(http.Flusher); ok {
+					w.Flush()
+				} else {
+					panic(errors.New("HotReload: ResponseWriter does not implement http.Flusher interface"))
+				}
+			}
+		}
+	}
+}
diff --git a/server/routes/www/www.go b/server/routes/www/www.go
index 8d54fea..d318863 100644
--- a/server/routes/www/www.go
+++ b/server/routes/www/www.go
@@ -1,14 +1,41 @@
 package www
 
 import (
+	"context"
+	"net/http"
+	"os"
+
 	"github.com/go-chi/chi/v5"
+	chimiddleware "github.com/go-chi/chi/v5/middleware"
+	"github.com/tigorlazuardi/redmage/config"
 	"github.com/tigorlazuardi/redmage/db/queries/subreddits"
+	"github.com/tigorlazuardi/redmage/pkg/log"
+	"github.com/tigorlazuardi/redmage/server/routes/middleware"
 )
 
+var PublicFS = os.DirFS("public")
+
 type WWW struct {
 	Subreddits *subreddits.Queries
+	Config     *config.Config
 }
 
 func (www *WWW) Register(router chi.Router) {
-	router.Get("/", www.Home)
+	router.Use(chimiddleware.RequestID)
+	router.Use(chimiddleware.RealIP)
+	router.
+		With(chimiddleware.RequestLogger(middleware.ChiSimpleLogger{})).
+		Mount("/public", http.StripPrefix("/public", http.FileServer(http.FS(PublicFS))))
+
+	if www.Config.Bool("http.hotreload") {
+		log.New(context.Background()).Debug("enabled hot reload")
+		router.
+			With(chimiddleware.RequestLogger(middleware.ChiSimpleLogger{})).
+			Get("/hot_reload", www.CreateHotReloadRoute())
+	}
+
+	router.Group(func(r chi.Router) {
+		r.Use(chimiddleware.RequestLogger(middleware.ChiLogger{}))
+		r.Get("/", www.Home)
+	})
 }
diff --git a/views/components/head.templ b/views/components/head.templ
new file mode 100644
index 0000000..6518f26
--- /dev/null
+++ b/views/components/head.templ
@@ -0,0 +1,17 @@
+package components
+
+import "github.com/tigorlazuardi/redmage/views"
+
+templ Head(vc *views.Context) {
+	<head>
+		<meta name="viewport" content="width=device-width, initial-scale=1.0"/>
+		<meta name="keywords" content="Reddit, Image, Downloader"/>
+		<link rel="stylesheet" href="/public/style.css"/>
+		<link rel="icon" href="/public/favicon.svg"/>
+		<script src="/public/htmx-1.9.11.min.js"></script>
+		<script src="/public/htmx-response-targets-1.9.11.min.js"></script>
+		if vc.Config.Bool("http.hotreload") {
+			<script src="/public/hot_reload.js"></script>
+		}
+	</head>
+}
diff --git a/views/context.go b/views/context.go
new file mode 100644
index 0000000..ec2e3b1
--- /dev/null
+++ b/views/context.go
@@ -0,0 +1,19 @@
+package views
+
+import (
+	"net/http"
+
+	"github.com/tigorlazuardi/redmage/config"
+)
+
+type Context struct {
+	Config  *config.Config
+	Request *http.Request
+}
+
+func NewContext(config *config.Config, request *http.Request) *Context {
+	return &Context{
+		Config:  config,
+		Request: request,
+	}
+}
diff --git a/views/homeview/homeview.templ b/views/homeview/homeview.templ
index fa152ae..9eb4455 100644
--- a/views/homeview/homeview.templ
+++ b/views/homeview/homeview.templ
@@ -1,5 +1,11 @@
 package homeview
 
-templ Home() {
-	<div>Hello World</div>
+import "github.com/tigorlazuardi/redmage/views/components"
+import "github.com/tigorlazuardi/redmage/views"
+
+templ Home(vc *views.Context) {
+	@components.Doctype() {
+		@components.Head(vc)
+		<div class="text-secondary">Hello World</div>
+	}
 }