// Copyright 2018 The Gitea Authors. All rights reserved.
// SPDX-License-Identifier: MIT

package activities

import (
	"context"

	"forgejo.org/models/db"
	"forgejo.org/models/organization"
	user_model "forgejo.org/models/user"
	"forgejo.org/modules/setting"
	"forgejo.org/modules/timeutil"
)

const (
	// contributionsMaxAgeSeconds How old data to retrieve for the heatmap.
	// 371 days to cover the entire heatmap (53 *full* weeks)
	contributionsMaxAgeSeconds = 32054400
)

// UserHeatmapData represents the data needed to create a heatmap
type UserHeatmapData struct {
	Timestamp     timeutil.TimeStamp `json:"timestamp"`
	Contributions int64              `json:"contributions"`
}

// GetUserHeatmapDataByUser returns an array of UserHeatmapData
func GetUserHeatmapDataByUser(ctx context.Context, user, doer *user_model.User) ([]*UserHeatmapData, error) {
	return getUserHeatmapData(ctx, user, nil, doer)
}

// GetUserHeatmapDataByUserTeam returns an array of UserHeatmapData
func GetUserHeatmapDataByUserTeam(ctx context.Context, user *user_model.User, team *organization.Team, doer *user_model.User) ([]*UserHeatmapData, error) {
	return getUserHeatmapData(ctx, user, team, doer)
}

func getUserHeatmapData(ctx context.Context, user *user_model.User, team *organization.Team, doer *user_model.User) ([]*UserHeatmapData, error) {
	hdata := make([]*UserHeatmapData, 0)

	if !ActivityReadable(user, doer) {
		return hdata, nil
	}

	// Group by 15 minute intervals which will allow the client to accurately shift the timestamp to their timezone.
	// The interval is based on the fact that there are timezones such as UTC +5:30 and UTC +12:45.
	groupBy := "created_unix / 900 * 900"
	if setting.Database.Type.IsMySQL() {
		groupBy = "created_unix DIV 900 * 900"
	}

	cond, err := activityQueryCondition(ctx, GetFeedsOptions{
		RequestedUser:  user,
		RequestedTeam:  team,
		Actor:          doer,
		IncludePrivate: true, // don't filter by private, as we already filter by repo access
		IncludeDeleted: true,
		// * Heatmaps for individual users only include actions that the user themself did.
		// * For organizations actions by all users that were made in owned
		//   repositories are counted.
		OnlyPerformedBy: !user.IsOrganization(),
	})
	if err != nil {
		return nil, err
	}

	return hdata, db.GetEngine(ctx).
		Select(groupBy+" AS timestamp, count(user_id) as contributions").
		Table("action").
		Where(cond).
		And("created_unix >= ?", timeutil.TimeStampNow()-contributionsMaxAgeSeconds).
		GroupBy("timestamp").
		OrderBy("timestamp").
		Find(&hdata)
}

// GetTotalContributionsInHeatmap returns the total number of contributions in a heatmap
func GetTotalContributionsInHeatmap(hdata []*UserHeatmapData) int64 {
	var total int64
	for _, v := range hdata {
		total += v.Contributions
	}
	return total
}
