import os
import psycopg2
import numpy as np
from psycopg2.extras import RealDictCursor
from datetime import datetime
from urllib.parse import urlparse
from flask import g


from utils import get_all_exercises_from_topsets, get_stats_from_topsets, get_workouts


class DataBase():
    def __init__(self, app):
        db_url = urlparse(os.environ['DATABASE_URL'])
        # if db_url is null then throw error
        if not db_url:
            raise Exception("No DATABASE_URL environment variable set")

    def getDB(self):
        db = getattr(g, 'database', None)
        if db is None:
            db_url = urlparse(os.environ['DATABASE_URL'])
            g.database = psycopg2.connect(
                database=db_url.path[1:],
                user=db_url.username,
                password=db_url.password,
                host=db_url.hostname,
                port=db_url.port
            )
            db = g.database
        return db

    def close_connection(exception):
        db = getattr(g, 'database', None)
        if db is not None:
            db.close()

    def execute(self, query, args=(), one=False, commit=False):
        conn = self.getDB()
        cur = conn.cursor(cursor_factory=RealDictCursor)
        cur.execute(query, args)
        rv = None
        if cur.description is not None:
            rv = cur.fetchall()
        if commit:
            try:
                conn.commit()
            except:
                conn.rollback()
        cur.close()

        return (rv[0] if rv else None) if one else rv

    def get_exercises(self):
        exercises = self.execute(
            'SELECT exercise_id AS "ExerciseId", name AS "Name" FROM exercise')
        return [{"ExerciseId": e['ExerciseId'], "Name": e['Name']} for e in exercises]

    def get_exercise(self, exercise_id):
        exercise = self.execute(
            'SELECT exercise_id AS "ExerciseId", name AS "Name" FROM exercise WHERE exercise_id=%s LIMIT 1', [exercise_id], one=True)
        return exercise

    def create_exercise(self, name):
        new_exercise = self.execute('INSERT INTO exercise (name) VALUES (%s) RETURNING exercise_id AS "ExerciseId"',
                                    [name], commit=True, one=True)
        return new_exercise['ExerciseId']

    def delete_exercise(self, exercise_id):
        self.execute('DELETE FROM exercise WHERE exercise_id=%s', [
            exercise_id], commit=True)

    def update_exercise(self, exercise_id, name):
        self.execute('UPDATE Exercise SET Name=%s WHERE exercise_id=%s', [
            name, exercise_id], commit=True)

    def get_people(self):
        people = self.execute(
            'SELECT person_id AS "PersonId", name AS "Name" FROM person')
        return people

    def is_valid_person(self, person_id):
        person = self.execute(
            'SELECT person_id AS "PersonId" FROM person WHERE person_id=%s LIMIT 1', [person_id], one=True)
        return person

    def create_person(self, name):
        new_person = self.execute('INSERT INTO person (name) VALUES (%s) RETURNING person_id AS "PersonId"', [
                                  name], commit=True, one=True)
        return new_person['PersonId']

    def delete_person(self, person_id):
        self.execute('DELETE FROM topset WHERE workout_id IN (SELECT workout_id FROM workout WHERE person_id=%s)', [
            person_id], commit=True)
        self.execute('DELETE FROM workout WHERE person_id=%s',
                     [person_id], commit=True)
        self.execute('DELETE FROM person WHERE person_id=%s',
                     [person_id], commit=True)

    def update_person_name(self, person_id, name):
        self.execute('UPDATE person SET name=%s WHERE person_id=%s', [
            name, person_id], commit=True)

    def is_valid_workout(self, person_id, workout_id):
        workout = self.execute('SELECT W.workout_id AS "WorkoutId" FROM Person P, Workout W WHERE P.person_id=W.person_id AND P.person_id=%s AND W.workout_id=%s LIMIT 1', [
            person_id, workout_id], one=True)
        return workout

    def is_valid_topset(self, person_id, workout_id, topset_id):
        topset = self.execute("""
            SELECT T.topset_id AS "TopSetId"
            FROM Person P, Workout W, TopSet T
            WHERE W.person_id=W.person_id AND W.workout_id=T.workout_id AND P.person_id=%s AND W.workout_id = %s AND T.topset_id = %s
            LIMIT 1""", [person_id, workout_id, topset_id], one=True)
        return topset

    def delete_workout(self, workout_id):
        self.execute('DELETE FROM topset WHERE workout_id=%s',
                     [workout_id], commit=True)
        self.execute('DELETE FROM workout WHERE workout_id=%s',
                     [workout_id], commit=True)

    def update_topset(self, exercise_id, repetitions, weight, topset_id):
        self.execute('UPDATE topset SET exercise_id=%s, repetitions=%s, weight=%s WHERE topSet_id=%s', [
            exercise_id, repetitions, weight, topset_id], commit=True)

    def create_topset(self, workout_id, exercise_id, repetitions, weight):
        new_top_set = self.execute('INSERT INTO topset (workout_id, exercise_id, repetitions, weight) VALUES (%s, %s, %s, %s) RETURNING topset_id AS "TopSetId"', [
            workout_id, exercise_id, repetitions, weight], commit=True, one=True)
        return new_top_set['TopSetId']

    def delete_topset(self, topset_id):
        self.execute('DELETE FROM topset WHERE topset_id=%s', [
            topset_id], commit=True)

    def create_workout(self, person_id):
        now = datetime.now()
        date_string = now.strftime('%Y-%m-%d')
        # check if a workout has already been created for this person today that doesnt contain any topsets and if so return the WorkoutId
        workout = self.execute('SELECT workout_id AS "WorkoutId" FROM workout WHERE person_id=%s AND start_date=%s AND workout_id NOT IN (SELECT workout_id FROM topset)', [
            person_id, date_string], one=True)
        if workout:
            print(
                f'Workout already created for PersonId {person_id} starting at {date_string} so returning WorkoutId {workout["WorkoutId"]} rather then creating new workout')
            return workout['WorkoutId']

        print(
            f'Creating workout for PersonId {person_id} starting at {date_string}')
        new_workout = self.execute('INSERT INTO workout (person_id, start_date) VALUES (%s, %s) RETURNING workout_id AS "WorkoutId"', [
            person_id, date_string], commit=True, one=True)
        return new_workout['WorkoutId']

    def get_people_and_workout_count(self, person_id):
        return self.execute("""
            SELECT
                P.person_id AS "PersonId",
                P.name AS "Name",
                COUNT(W.workout_id) AS "NumberOfWorkouts",
                CASE P.person_id
                    WHEN %s
                        THEN 1
                        ELSE 0
                    END "IsActive"
            FROM
                Person P LEFT JOIN Workout W ON P.person_id = W.person_id
            GROUP BY
                P.person_id
            ORDER BY
                P.person_id""", [person_id])

    def update_workout_start_date(self, workout_id, start_date):
        self.execute('UPDATE workout SET start_date=%s WHERE workout_id=%s', [
            start_date, workout_id], commit=True)

    def get_person(self, person_id):
        topsets = self.execute("""
            SELECT
                P.person_id AS "PersonId",
                P.name AS "PersonName",
                W.workout_id AS "WorkoutId",
                W.start_date AS "StartDate",
                T.topset_id AS "TopSetId",
                E.exercise_id AS "ExerciseId",
                E.name AS "ExerciseName",
                T.repetitions AS "Repetitions",
                T.weight AS "Weight",
                round((100 * T.Weight::numeric::integer)/(101.3-2.67123 * T.Repetitions),0)::numeric::integer AS "Estimated1RM"
            FROM Person P
                LEFT JOIN Workout W ON P.person_id=W.person_id
                LEFT JOIN TopSet T ON W.workout_id=T.workout_id
                LEFT JOIN Exercise E ON T.exercise_id=E.exercise_id
            WHERE P.person_id=%s""", [person_id])

        return {
            'PersonId': next((t['PersonId'] for t in topsets), -1),
            'PersonName': next((t['PersonName'] for t in topsets), 'Unknown'),
            'Stats': get_stats_from_topsets(topsets),
            'Exercises': get_all_exercises_from_topsets(topsets),
            'Workouts': get_workouts(topsets)
        }

    def get_workout(self, person_id, workout_id):
        topsets = self.execute("""
            SELECT
                P.person_id AS "PersonId",
                P.name AS "PersonName",
                W.workout_id AS "WorkoutId",
                W.start_date AS "StartDate",
                T.topset_id AS "TopSetId",
                E.exercise_id AS "ExerciseId",
                E.name AS "ExerciseName",
                T.repetitions AS "Repetitions",
                T.weight AS "Weight",
                W.note AS "Note"
            FROM Person P
                LEFT JOIN Workout W ON P.person_id=W.person_id
                LEFT JOIN TopSet T ON W.workout_id=T.workout_id
                LEFT JOIN Exercise E ON T.exercise_id=E.exercise_id
            WHERE P.person_id=%s
                AND W.workout_id = %s
            ORDER BY T.topset_id""", [person_id, workout_id])

        note = next((t['Note'] for t in topsets), '')

        return {
            'PersonId': person_id,
            'PersonName': next((t['PersonName'] for t in topsets), 'Unknown'),
            'WorkoutId': workout_id,
            'StartDate': topsets[0]['StartDate'],
            'TopSets': [{"TopSetId": t['TopSetId'], "ExerciseId": t['ExerciseId'], "ExerciseName": t['ExerciseName'], "Weight": t['Weight'], "Repetitions": t['Repetitions']} for t in topsets if t['TopSetId'] is not None],
            'Note': note
        }

    def get_topset(self, person_id, workout_id, topset_id):
        topset = self.execute("""
            SELECT
                P.person_id AS "PersonId",
                P.name AS "PersonName",
                W.workout_id AS "WorkoutId",
                W.start_date AS "StartDate",
                T.topset_id AS "TopSetId",
                E.exercise_id AS "ExerciseId",
                E.name AS "ExerciseName",
                T.repetitions AS "Repetitions",
                T.weight AS "Weight"
            FROM Person P
                INNER JOIN Workout W ON P.person_id=W.person_id
                INNER JOIN TopSet T ON W.workout_id=T.workout_id
                INNER JOIN Exercise E ON T.exercise_id=E.exercise_id
            WHERE P.person_id=%s
                AND W.workout_id = %s
                AND T.topset_id = %s""", [person_id, workout_id, topset_id], one=True)

        return {
            'PersonId': topset['PersonId'],
            'PersonName': topset['PersonName'],
            'WorkoutId': workout_id,
            'StartDate': topset['StartDate'],
            'Exercises': self.get_exercises(),
            "TopSetId": topset['TopSetId'],
            "ExerciseId": topset['ExerciseId'],
            "ExerciseName": topset['ExerciseName'],
            "Weight": topset['Weight'],
            "Repetitions": topset['Repetitions']
        }

    def get_all_topsets(self):
        all_topsets = self.execute("""
            SELECT
            P.person_id AS "PersonId",
            P.name AS "PersonName",
            W.workout_id AS "WorkoutId",
            W.start_date AS "StartDate",
            T.topset_id AS "TopSetId",
            E.exercise_id AS "ExerciseId",
            E.name AS "ExerciseName",
            T.repetitions AS "Repetitions",
            T.weight AS "Weight",
            round((100 * T.Weight::numeric::integer)/(101.3-2.67123 * T.Repetitions),0)::numeric::integer AS "Estimated1RM"
        FROM Person P
            LEFT JOIN Workout W ON P.person_id=W.person_id
            LEFT JOIN TopSet T ON W.workout_id=T.workout_id
            LEFT JOIN Exercise E ON T.exercise_id=E.exercise_id""")

        return all_topsets

    def get_tags_for_person(self, person_id):
        return self.execute("""
            SELECT
                T.tag_id AS "TagId",
                T.person_id AS "PersonId",
                T.name AS "TagName",
                T.filter AS "TagFilter"
            FROM
                Tag T
            WHERE
                T.person_id = %s
            ORDER BY
                T.name""", [person_id])

    def add_or_update_tag_for_person(self, person_id, tag_name, tag_filter):
        # check if a tag exists for dashboard with the same tag_name
        tag = self.execute('SELECT tag_id AS "TagId" FROM Tag WHERE person_id=%s AND name=%s LIMIT 1', [
            person_id, tag_name], one=True)
        if tag:
            # update the tag
            self.execute('UPDATE Tag SET filter=%s WHERE tag_id=%s', [
                         tag_filter, tag['TagId']], commit=True)
        else:
            self.execute('INSERT INTO Tag (person_id, name, filter) VALUES (%s, %s, %s)', [
                person_id, tag_name, tag_filter], commit=True)

    def delete_tag_for_person(self, person_id, tag_id):
        self.execute('DELETE FROM Tag WHERE person_id=%s AND tag_id=%s', [
            person_id, tag_id], commit=True)

    def get_tags_for_dashboard(self):
        return self.execute("""
            SELECT
                T.tag_id AS "TagId",
                T.person_id AS "PersonId",
                T.name AS "TagName",
                T.filter AS "TagFilter"
            FROM
                Tag T
            WHERE
                T.person_id IS NULL
            ORDER BY
                T.name""", [])

    def add_or_update_tag_for_dashboard(self, tag_name, tag_filter):
        # check if a tag exists for dashboard with the same tag_name
        tag = self.execute('SELECT tag_id AS "TagId" FROM Tag WHERE person_id IS NULL AND name=%s LIMIT 1', [
            tag_name], one=True)
        if tag:
            # update the tag
            self.execute('UPDATE Tag SET filter=%s WHERE tag_id=%s', [
                         tag_filter, tag['TagId']], commit=True)
        else:
            self.execute('INSERT INTO Tag (name, filter) VALUES (%s, %s)', [
                tag_name, tag_filter], commit=True)

    def delete_tag_for_dashboard(self, tag_id):
        self.execute('DELETE FROM Tag WHERE tag_id=%s', [tag_id], commit=True)

    def update_workout_note_for_person(self, person_id, workout_id, note):
        self.execute('UPDATE workout SET note=%s WHERE person_id=%s AND workout_id=%s', [
            note, person_id, workout_id], commit=True)

    def add_tag_for_workout(self, workout_id, tags_id):
        # First, delete tags that are not in the new selection
        self.execute(
            """
            DELETE FROM workout_tag 
            WHERE workout_id = %s AND tag_id NOT IN %s
            """,
            [workout_id, tuple(tags_id)], commit=True
        )

        # Then, attempt to insert the new tags
        for tag_id in tags_id:
            self.execute(
                """
                INSERT INTO workout_tag (workout_id, tag_id) 
                VALUES (%s, %s)
                ON CONFLICT (workout_id, tag_id) DO NOTHING
                """,
                [workout_id, tag_id], commit=True
            )

        # Now fetch updated list of workout tags
        workout_tags = self.execute("""
            SELECT
                T.tag_id AS "tag_id",
                T.person_id AS "person_id",
                T.name AS "tag_name",
                T.filter AS "tag_filter"
            FROM Workout_Tag WT
                LEFT JOIN Tag T ON WT.tag_id=T.tag_id
            WHERE WT.workout_id=%s""", [workout_id])

        return workout_tags

    def create_tag_for_workout(self, person_id, workout_id, tag_name):
        workout_exercises = self.execute("""
            SELECT
                E.exercise_id AS "exercise_id",
                E.name AS "exercise_name"
            FROM Workout W
                LEFT JOIN TopSet T ON W.workout_id=T.workout_id
                LEFT JOIN Exercise E ON T.exercise_id=E.exercise_id
            WHERE W.workout_id=%s""", [workout_id])

        tag_filter = "?" + \
            "&".join(
                f"exercise_id={e['exercise_id']}" for e in workout_exercises)

        # create tag for person
        row = self.execute('INSERT INTO Tag (person_id, name, filter) VALUES (%s, %s, %s) RETURNING tag_id AS "tag_id"', [
            person_id, tag_name, tag_filter], commit=True, one=True)

        # add tag to workout
        self.execute('INSERT INTO Workout_Tag (workout_id, tag_id) VALUES (%s, %s)', [
            workout_id, row['tag_id']], commit=True)

        # Now fetch updated list of workout tags
        workout_tags = self.execute("""
            SELECT
                T.tag_id AS "tag_id",
                T.person_id AS "person_id",
                T.name AS "tag_name",
                T.filter AS "tag_filter"
            FROM Workout_Tag WT
                LEFT JOIN Tag T ON WT.tag_id=T.tag_id
            WHERE WT.workout_id=%s""", [workout_id])

        return workout_tags

    def get_workout_tags(self, person_id, workout_id):
        person_tags = self.execute("""
            SELECT
                T.tag_id AS "tag_id",
                T.name AS "tag_name",
                T.filter AS "tag_filter"
            FROM Tag T
            WHERE T.person_id=%s""", [person_id])

        workout_tags = self.execute("""
            SELECT
                T.tag_id AS "tag_id",
                T.person_id AS "person_id",
                T.name AS "tag_name",
                T.filter AS "tag_filter"
            FROM Workout_Tag WT
                LEFT JOIN Tag T ON WT.tag_id=T.tag_id
            WHERE WT.workout_id=%s""", [workout_id])

        selected_workout_tag_ids = [wt['tag_id'] for wt in workout_tags]

        return (person_tags, workout_tags, selected_workout_tag_ids)

    def get_most_recent_topset_for_exercise(self, person_id, exercise_id):
        topset = self.execute("""
            SELECT 
                t.repetitions, 
                t.weight
            FROM 
                topset t JOIN workout w ON t.workout_id = w.workout_id
            WHERE 
                w.person_id = %s AND t.exercise_id = %s
            ORDER BY 
                w.start_date DESC
            LIMIT 1;
        """, [person_id, exercise_id], one=True)

        if not topset:
            return None
        else:
            return (topset['repetitions'], topset['weight'])

    def get_all_exercises(self):
        exercises = self.execute(
            'SELECT exercise_id, name FROM exercise')
        return exercises
    
    def get_exercise_progress_for_user(self, person_id, exercise_id):
        # Execute SQL query to fetch topset data for a specific person and exercise
        topsets = self.execute("""
            SELECT 
                T.topset_id, E.name AS exercise_name, W.person_id, T.workout_id,
                T.repetitions, T.weight,
                ROUND((100 * T.weight::NUMERIC::INTEGER) / (101.3 - 2.67123 * T.repetitions), 0)::NUMERIC::INTEGER AS estimated_1rm,
                W.start_date
            FROM 
                topset T
            JOIN 
                exercise E ON T.exercise_id = E.exercise_id
            JOIN 
                workout W ON T.workout_id = W.workout_id
            WHERE
                W.person_id = %s AND E.exercise_id = %s
            ORDER BY 
                W.start_date;
        """, [person_id, exercise_id])

        # Return None if no topsets found
        if not topsets:
            return None

        # Extracting values and calculating value ranges for SVG dimensions
        estimated_1rm = [t['estimated_1rm'] for t in topsets]
        repetitions = [t['repetitions'] for t in topsets]
        weight = [t['weight'] for t in topsets]
        start_dates = [t['start_date'] for t in topsets]
        min_date, max_date = min(start_dates), max(start_dates)
        min_e1rm, max_e1rm = min(estimated_1rm), max(estimated_1rm)
        min_reps, max_reps = min(repetitions), max(repetitions)
        min_weight, max_weight = min(weight), max(weight)
        
        # Calculate viewBox dimensions
        date_range = max_date - min_date
        e1rm_range = max_e1rm - min_e1rm
        reps_range = max_reps - min_reps
        weight_range = max_weight - min_weight
        vb_width, vb_height = date_range.days, e1rm_range
        vb_width *= 200 / vb_width  # Scale to 200px width
        vb_height *= 75 / vb_height  # Scale to 75px height

        # Scale estimated_1rm values for SVG plotting
        precision = 3
        estimated_1rm_scaled = [round(((value - min_e1rm) / e1rm_range) * vb_height, precision) for value in estimated_1rm]
        repetitions_scaled = [round(((value - min_reps) / reps_range) * vb_height, precision) for value in repetitions]
        weight_scaled = [round(((value - min_weight) / weight_range) * vb_height, precision) for value in weight]
        total_span = date_range.days or 1
        relative_positions = [round((date - min_date).days / total_span, precision) for date in start_dates]

        # Convert relative positions and scaled estimated 1RM values to numpy arrays
        x = np.array(relative_positions)
        y = np.array(estimated_1rm_scaled)

        # Calculate the slope (m) and y-intercept (b) of the line of best fit
        m, b = np.polyfit(x, y, 1)

        # Generate points along the line of best fit
        y_best_fit = [m * xi + b for xi in x]
        best_fit_points = zip(y_best_fit, relative_positions)

        # Create messages and zip data for SVG plotting
        messages = [f'{t["repetitions"]} x {t["weight"]}kg ({t["estimated_1rm"]}kg E1RM) on {t["start_date"].strftime("%d %b %y")}' for t in topsets]
        estimated_1rm_points = zip(estimated_1rm_scaled, relative_positions, messages)
        repetitions_points = zip(repetitions_scaled, relative_positions, messages)
        weight_points = zip(weight_scaled, relative_positions, messages)

        estimated_1rm = {
            'label': 'E1RM',
            'color': '#2ca02c',
            'points': list(estimated_1rm_points)
        }
        repetitions = {
            'label': 'Reps',
            'color': '#388fed',
            'points': list(repetitions_points)
        }
        weight = {
            'label': 'Weight',
            'color': '#bd3178',
            'points': list(weight_points)
        }

        # Return exercise data with SVG dimensions and data points
        return {
            'exercise_name': topsets[0]['exercise_name'],
            'vb_width': vb_width,
            'vb_height': vb_height,
            'plots': [estimated_1rm, repetitions, weight],
            'best_fit_points': list(best_fit_points),
        }