Update main with observability check

src/iact_estimator/scripts/main.py

@@ -22,6 +22,7 @@
     calculate,
 )
 from ..plots import plot_spectrum, plot_sed, plot_transit, plot_altitude_airmass
+from ..observability import define_constraints, check_observability
 from .. import RESOURCES_PATH
 
 parser = argparse.ArgumentParser()
@@ -127,6 +128,53 @@ def main():
             seaborn_options = config["seaborn_options"]
             sns.set_theme(**seaborn_options)
 
+        # Basic observability checks
+        target_source = FixedTarget.from_name(source_name)
+        observer = Observer.at_site("Roque de los Muchachos")
+        time = Time(config["observation_datetime"])
+
+        crab = FixedTarget.from_name("Crab")
+
+        constraints = define_constraints(config)
+
+        time_range = config["observation"]["datetime"] + 1 * u.year
+
+        ever_observable, always_observable, best_months = check_observability(
+            constraints, observer, target_source, time_range
+        )
+
+        if not ever_observable:
+            logger.info("The source is never observable from this location!")
+            parser.exit(0)
+
+        logger.info(f"The best months to observe the target source are {best_months}.")
+
+        with quantity_support():
+            plot_transit(
+                config,
+                source_name,
+                target_source,
+                observer,
+                time,
+                merge_profiles=config["plotting_options"]["merge_horizon_profiles"],
+                plot_crab=True if (crab.coord == target_source.coord) else False,
+                style_kwargs=None,
+                savefig=True,
+                output_path=output_path,
+            )
+
+            plot_altitude_airmass(
+                config,
+                source_name,
+                target_source,
+                observer,
+                time,
+                brightness_shading=True,
+                airmass_yaxis=True,
+                savefig=True,
+                output_path=output_path,
+            )
+
         logger.info("Initializing assumed model")
         assumed_spectrum = initialize_model(config)
 
@@ -175,38 +223,6 @@ def main():
 
         logger.info("All expected operations have been perfomed succesfully.")
 
-        target_source = FixedTarget.from_name(source_name)
-        observer = Observer.at_site("Roque de los Muchachos")
-        time = Time(config["observation_datetime"])
-
-        crab = FixedTarget.from_name("Crab")
-
-        with quantity_support():
-            plot_transit(
-                config,
-                source_name,
-                target_source,
-                observer,
-                time,
-                merge_profiles=config["plotting_options"]["merge_horizon_profiles"],
-                plot_crab=True if (crab.coord == target_source.coord) else False,
-                style_kwargs=None,
-                savefig=True,
-                output_path=output_path,
-            )
-
-            plot_altitude_airmass(
-                config,
-                source_name,
-                target_source,
-                observer,
-                time,
-                brightness_shading=True,
-                airmass_yaxis=True,
-                savefig=True,
-                output_path=output_path,
-            )
-
         if config["plotting_options"]["show"]:
             plt.show()