import sys
from math import sqrt, degrees, acos
from helix.models.corner import Corner
from helix.constants.global_constants import max_corner_angle
import flask_featureflags as feature

class ProjectPresenter(object):
    def __init__(self, system_type, module_type):
        self.offset = None
        self.system_type = system_type
        self.module_type = module_type

    '''"This function expects coordinates to be in unit values, processed in coordinates_calculator.py" '''
    def get_panel_data(self, panels, subarrays, max_y = None):
        if self.offset is not None:
            raise RuntimeError("ProjectPresenter panels must be computed before buildings")

        table_data = []

        system_constants = self.system_type.system_constants()
        module_constants = self.system_type.module_constants(self.module_type)
        spacing_x, spacing_y = module_constants.presenter_spacing
        wind_zones = system_constants.wind_zones

        for panel in panels:
            subarray = [x for x in subarrays if x.subarray_number == panel.subarray][0]
            origin = subarray.origin

            table_data.append({
                'x': (panel.coordinate.x + origin.x) * spacing_x,
                'y': (panel.coordinate.y + origin.y) * spacing_y,
                'width': spacing_x,
                'height': spacing_y,
                'data': {
                    'panel_id': panel.id,
                    'panel_type': panel.panel_type.number(),
                    'ballast': panel.ballast,
                    'wind_anchors': panel.wind_anchors,
                    'seismic_anchors': panel.seismic_anchors,
                    'wind_zones': wind_zones[panel.wind_zone],
                    'link_trays': panel.presented_link_tray,
                    'cross_trays': panel.cross_tray,
                    'psf': round(panel.pressure, 2),
                    'subarray': panel.subarray
                }
            })

        # Move coordinates to reflect origin being at top-left
        # (as per canvas) instead of bottom-left
        height = max(map(lambda row: row['y'], table_data))
        first_cell = min(map(lambda row: row['y'], table_data))
        self.offset = height
        for panel in table_data:
            panel['y'] = height - panel['y'] + first_cell

        return table_data

    def get_buildings(self, buildings, max_y):
        if self.offset is None:
            self.offset = 0

        module_constants = self.system_type.module_constants(self.module_type)
        spacing_x, spacing_y = module_constants.presenter_spacing
        # max_y = -sys.maxsize - 1 # for flipping the y coordinate

        result = []
        for building in buildings:
            presentable_building = []
            result.append(presentable_building)
            # origin = self.find_origin(building)
            for point in building:
                point.x = point.x * spacing_x
                point.y = abs((point.y * spacing_y) - max_y)
                presentable_building.append(point.__dict__)

        return result

    def get_corners(self, buildings):
        
        def angle(x1, y1, x2, y2):
            # Use dotproduct to find angle between vectors
            # This always returns an angle between 0, pi
            numer = (x1 * x2 + y1 * y2)
            denom = sqrt((x1 ** 2 + y1 ** 2) * (x2 ** 2 + y2 ** 2))
            return acos(numer / denom) 


        def cross_sign(x1, y1, x2, y2):
            # True if cross is positive
            # False if negative or zero
            return x1 * y2 > x2 * y1
          
        result = []
        if feature.is_active('ff_cpp'):
          for building in buildings:
            presentable_building = []
            result.append(presentable_building)
            
            for i in range(len(building)):
                p1 = building[i]
                ref = building[i - 1]
                p2 = building[i - 2]
                x1, y1 = p1[0] - ref[0], p1[1] - ref[1]
                x2, y2 = p2[0] - ref[0], p2[1] - ref[1]

                corner_length_cw = sqrt(x2**2 + y2**2)
                corner_length_ccw = sqrt(x1**2 + y1**2)
                theta = degrees(angle(x1, y1, x2, y2))

                #print('Points', p1, ref, p2)
                #print('Angle', theta)
                if (cross_sign(x1, y1, x2, y2)) and (theta < max_corner_angle) :
                    #print('Inner Angle')
                    presentable_building.append(Corner(ref[0], ref[1], corner_length_ccw,corner_length_cw, theta).__dict__)
        return result

    def get_max_y(self,buildings, panels):

        module_constants = self.system_type.module_constants(self.module_type)
        _, spacing_y = module_constants.presenter_spacing
        all_y = []

        if buildings is None or buildings == []: # no buildings in the file, probably CSV coordinates loaded
            for panel in panels:
                all_y.append(panel.coordinate.y)

        for building in buildings:
            for point in building:
                all_y.append(point.y)
        return max(all_y) * spacing_y