improve chart colors and fontsizes

app/rest/pyapi.py

@@ -22,9 +22,11 @@ from bottle import (
     static_file,
     TEMPLATE_PATH,
 )
+from matplotlib.axes import Axes
 TEMPLATE_PATH.append("app/rest/templates")
 from psycopg import connect
 from psycopg.sql import SQL, Literal
+from pandas import DataFrame
 import matplotlib.pyplot as plt
 import seaborn as sns
 from multiprocessing import Lock
@@ -39,14 +41,6 @@ from ..data.util import(
 import matplotlib
 matplotlib.use('agg')
 
-def line(pivot, ylabel=None, xlabel=None):
-    ax = sns.lineplot(data=pivot, markers=True)
-    ax.set_xlabel(xlabel, color='#cccccc')
-    ax.set_ylabel(ylabel, color='#cccccc')
-    ax.axes.tick_params(colors='#cccccc', which='both')
-    for _, spine in ax.spines.items():
-        spine.set_color('#cccccc')
-
 ALL_UNITS = {'g', 'kg', 'mL', 'L', 'Pieces', 'Bunches', 'Bags'}
 PARAMS = { 'group', 'category', 'product', 'unit', 'tag' }
 CACHE = dict()
@@ -269,10 +263,33 @@ def trend_internal(path, query):
             
             progress.append({ "name": "Loading chart", "status": ""})
             yield template("loading", progress=progress)
+            
             pivot = data.pivot_table(index=['ts_raw',], columns=['product',], values=['$/unit'], aggfunc='mean')
             pivot.columns = pivot.columns.droplevel()
-            plt.figure(facecolor='black', figsize=[16, 9])
-            line(pivot, xlabel='Time', ylabel=f'$ / {unit}')
+            
+            sns.set(style="darkgrid", palette='pastel', context="talk")
+            plt.style.use("dark_background")
+            plt.rcParams.update({"grid.linewidth":0.1, "grid.alpha":0.5})
+            plt.figure(figsize=[16, 9], layout="tight")
+            xlabel='Time'
+            ylabel=f'$ / {unit}'
+            if pivot.columns.size > 50:
+                ax = sns.scatterplot(data=pivot, markers=True)
+            else:
+                ax = sns.lineplot(data=pivot, markers=True)
+                legend = plt.figlegend(
+                    loc='upper center', ncol=6,
+                    title_fontsize="14", fontsize="12", labelcolor='#a0a0a0',
+                    framealpha=0.5
+                )
+                legend.set_title(title="Products")
+            ax.legend().set_visible(False)
+
+            ax.set_xlabel(xlabel, color='#a0a0a0', fontsize="14")
+            ax.set_ylabel(ylabel, color='#a0a0a0', fontsize="14")
+            ax.axes.tick_params(colors='#a0a0a0', labelsize="12", which='both')
+            for _, spine in ax.spines.items():
+                spine.set_color('#a0a0a0')
             
             progress[-1]["status"] = "done"
             yield template("loading", progress=progress)
@@ -287,7 +304,6 @@ def trend_internal(path, query):
             progress[-1]["status"] = "done"
             yield template("loading", progress=progress)
             
-            final = template("trend", form=form, svg=f.getvalue())
             resp = lambda: template("trend", form=form, svg=f.getvalue())
 
     except HTTPError as e: