#Initial setting
coding: utf-8

layer = iface.activeLayer()

#Data to be filled in manually, based on fisher sightings (example in bold).
dia=1 #Inserting sighting day (Note: it does not accept leading zeros, i. e. dates 01 to 09 must be typed only as 1... 9)
hora=str('12:13') #Inserting the sighting time (note: it must be enclosed in single quotes, be careful not to erase the quotes!)
idponto1=142 #Using the row number from the excel worksheet closest to the sighting time
idponto2=idponto1+1
t0=43980 #Inserting sighting time converted to seconds (multiply by 86400)
sp=str('Caretta caretta') #Inserting species name. It must be enclosed in single quotes, be careful not to delete the quotes!
n=1 #Inserting the sighting number

#1. Selecting two points between the sighting. For example: sighting time is 8:33 (named as p3), and shoul be selected time points at 8:30 (p1) and 8:35 (p2) recorded.
#Selection of two points
layer.select(idponto1)
for f in layer.selectedFeatures():
    xa = f['X']
    ya = f['Y']
    ta = f['segundos']
layer.removeSelection()

layer.select(idponto2)
for f in layer.selectedFeatures():
    xb = f['X']
    yb = f['Y']
    tb = f['segundos']
layer.removeSelection()

point1 = QgsPointXY(xa,ya)
point2 = QgsPointXY(xb,yb)

#2. Calculating distance between two points (p1 and p2) in meters
distance = QgsDistanceArea()
m = distance.measureLine(point1, point2)
print ("distancia:", m)

#3. Calculating the time, in seconds, between two points (p1 and p2). The tracker was configured to use a 5-minute interval, however, due to data acquisition instability, location acquisitions can vary
t= tb-ta
print ("segundos:", t)

#4. Using the average velocity formula (Vm=ΔD/ΔT) between two points
vm=m/t
print ("velocidade media", vm)

#5. Creating a line between two points (p1 e p2)
point1 = QgsPoint(xa,ya)
point2 = QgsPoint(xb,yb)

c = QgsVectorLayer('LineString?crs=epsg:4326&field=gid:integer', 'linha', 'memory')
if c != None and c.isValid() :
    c.setProviderEncoding('UTF-8')
    caps = c.dataProvider().capabilities() #capabilities returns the capabilities (functionalities) available in the layer

     #Checking if it is possible to add features into the layer
    if caps and QgsVectorDataProvider.AddFeatures :
        feicao = QgsFeature(c.fields())
        #Creating first feature
        feicao.setAttribute("gid",1);
        geom = QgsGeometry.fromPolyline([point1,point2]) 
        feicao.setGeometry(geom) #Including the geometry into the feature
        #addFeatures returns two values:
        #First is True if features were added
        #Second is an object list with the added features
        (res, resFeicoes) = c.dataProvider().addFeatures([feicao])
        QgsProject.instance().addMapLayers([c]) #Adding the created layer to the canvas

#6. Inserting a new time (difference between the previous time and the sighting time), in seconds. Example: p3 – p1 = 3 min = 180 s.
t=t0-ta

#7. Calculating distance until the indicated time, using previously average speed calculated.
d0=vm*t
print ("distancia ponto:", d0)

point1 = QgsPointXY(xa,ya)
point2 = QgsPointXY(xb,yb)


#8. Creating a buffer with the distance until the indicated time.
b = QgsVectorLayer('LineString?crs=epsg:4326&field=gid:integer', 'buffer', 'memory')
if b != None and c.isValid() :
    b.setProviderEncoding('UTF-8')
    caps = b.dataProvider().capabilities() #capabilities returns the capabilities (functionalities) available in the layer
     #Checking if it is possible to add features into the layer
    if caps and QgsVectorDataProvider.AddFeatures :
        feicao = QgsFeature(b.fields())
        #Creating first feature
        feicao.setAttribute("gid",1);
        geome = QgsGeometry.fromPointXY(point1).buffer(d0,0)
        geometry = QgsGeometry.asQPolygonF(geome)
        g = QgsGeometry.createPolylineFromQPolygonF(geometry)
        ge = QgsGeometry.fromPolylineXY(g)
        feicao.setGeometry(ge) #Including the geometry into the feature
        #addFeatures returns two values:
        #First is True if features were added
        #Second is an object list with the added features
        (res, resFeicoes) = b.dataProvider().addFeatures([feicao])
        QgsProject.instance().addMapLayers([b]) #Adding the created layer to the canvas

#9. Making a line intersection between the buffer and the distance line and creating a point at this intersection (p3).
# Creating a line between the points 
a = QgsVectorLayer('Point?crs=epsg:4326&field=gid:integer&field=especie:string&field=data:integer&field=hora:string', 'ponto {}'.format(n), 'memory')
if a != None and a.isValid() :
    a.setProviderEncoding('UTF-8')
    caps = a.dataProvider().capabilities() #capabilities returns the capabilities (functionalities) available in the layer
    #Checking if it is possible to add features into the layer
    if caps and QgsVectorDataProvider.AddFeatures :
        feicao = QgsFeature(a.fields())
        #Creating first feature
        feicao.setAttribute("gid",n);
        feicao.setAttribute("especie",sp);
        feicao.setAttribute("data",dia);
        feicao.setAttribute("hora",hora);
        p1 = QgsGeometry.intersection(geom,ge)
        feicao.setGeometry(p1) #Including the geometry into the feature
        #addFeatures returns two values:
        #First is True if features were added
        #Second is an object list with the added features
        (res, resFeicoes) = a.dataProvider().addFeatures([feicao])
        #adiciona a camada criada na tela
        QgsProject.instance().addMapLayers([a]) 

QgsProject.instance().removeMapLayer(b)
QgsProject.instance().removeMapLayer(c)