feat(dashboard): #82 add chart for sum of account and savings

internal/handler/dashboard.go

@@ -0,0 +1,145 @@
+package handler
+
+import (
+	"fmt"
+	"log/slog"
+	"net/http"
+	"spend-sparrow/internal/handler/middleware"
+	"spend-sparrow/internal/service"
+	"spend-sparrow/internal/template/dashboard"
+	"spend-sparrow/internal/types"
+	"spend-sparrow/internal/utils"
+	"time"
+
+	"github.com/a-h/templ"
+)
+
+type Dashboard interface {
+	Handle(router *http.ServeMux)
+}
+
+type DashboardImpl struct {
+	r *Render
+	d *service.Dashboard
+	c service.Clock
+}
+
+func NewDashboard(r *Render, d *service.Dashboard, c service.Clock) Dashboard {
+	return DashboardImpl{
+		r: r,
+		d: d,
+		c: c,
+	}
+}
+
+func (handler DashboardImpl) Handle(router *http.ServeMux) {
+	router.Handle("GET /dashboard", handler.handleDashboard())
+	router.Handle("GET /dashboard/dataset", handler.handleDashboardDataset())
+}
+
+func (handler DashboardImpl) handleDashboard() http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		updateSpan(r)
+
+		user := middleware.GetUser(r)
+		if user == nil {
+			utils.DoRedirect(w, r, "/auth/signin")
+			return
+		}
+
+		var comp templ.Component
+		htmx := utils.IsHtmx(r)
+
+		var err error
+		comp, err = handler.dashboard(user, r)
+		if err != nil {
+			slog.ErrorContext(r.Context(), "Failed to get dashboard summary", "err", err)
+		}
+
+		if htmx {
+			handler.r.RenderWithStatus(r, w, comp, http.StatusOK)
+		} else {
+			handler.r.RenderLayoutWithStatus(r, w, comp, user, http.StatusOK)
+		}
+	}
+}
+
+func (handler DashboardImpl) handleDashboardDataset() http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		updateSpan(r)
+
+		user := middleware.GetUser(r)
+
+		series, err := handler.d.MainChart(r.Context(), user)
+		if err != nil {
+			handleError(w, r, err)
+			return
+		}
+
+		w.Header().Set("Content-Type", "application/json")
+		w.WriteHeader(http.StatusOK)
+
+		account := ""
+		savings := ""
+
+		for _, entry := range series {
+			account += fmt.Sprintf(`["%s",%.2f],`, entry.Day.Format(time.RFC3339), float64(entry.Value)/100)
+			savings += fmt.Sprintf(`["%s",%.2f],`, entry.Day.Format(time.RFC3339), float64(entry.Savings)/100)
+		}
+		account = account[:len(account)-1]
+		savings = savings[:len(savings)-1]
+
+		_, err = fmt.Fprintf(w, `
+			{
+				"tooltip": {
+					"trigger": "axis",
+					"formatter": "<updated by client>"
+				},
+				"xAxis": {
+					"type": "time"
+				},
+				"yAxis": {
+					"axisLabel": {
+						"formatter": "{value} €"
+					}
+				},
+				"series": [
+					{
+						"data": [%s],
+						"type": "line",
+						"name": "Account Value"
+					},
+					{
+						"data": [%s],
+						"type": "line",
+						"name": "Savings"
+					}
+				]
+			}
+		`, account, savings)
+		if err != nil {
+			slog.InfoContext(r.Context(), "could not write response", "err", err)
+		}
+	}
+}
+
+func (handler DashboardImpl) dashboard(user *types.User, r *http.Request) (templ.Component, error) {
+	var month time.Time
+	var err error
+	monthStr := r.URL.Query().Get("month")
+	if monthStr != "" {
+		month, err = time.Parse("2006-01-02", monthStr)
+		if err != nil {
+			return nil, fmt.Errorf("could not parse timestamp: %w", service.ErrBadRequest)
+		}
+	} else {
+		month = handler.c.Now()
+	}
+
+	summary, err := handler.d.Summary(r.Context(), user, month)
+	if err != nil {
+		return nil, err
+	}
+
+	return dashboard.Dashboard(summary), nil
+}