1 files changed, 242 insertions, 0 deletions
diff --git a/models/repo/language_stats.go b/models/repo/language_stats.go
new file mode 100644
index 00000000..0bc0f1fb
--- /dev/null
+++ b/models/repo/language_stats.go
@@ -0,0 +1,242 @@
+// Copyright 2020 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package repo
+
+import (
+	"context"
+	"math"
+	"sort"
+	"strings"
+
+	"code.gitea.io/gitea/models/db"
+	"code.gitea.io/gitea/modules/timeutil"
+
+	"github.com/go-enry/go-enry/v2"
+)
+
+// LanguageStat describes language statistics of a repository
+type LanguageStat struct {
+	ID          int64 `xorm:"pk autoincr"`
+	RepoID      int64 `xorm:"UNIQUE(s) INDEX NOT NULL"`
+	CommitID    string
+	IsPrimary   bool
+	Language    string             `xorm:"VARCHAR(50) UNIQUE(s) INDEX NOT NULL"`
+	Percentage  float32            `xorm:"-"`
+	Size        int64              `xorm:"NOT NULL DEFAULT 0"`
+	Color       string             `xorm:"-"`
+	CreatedUnix timeutil.TimeStamp `xorm:"INDEX CREATED"`
+}
+
+func init() {
+	db.RegisterModel(new(LanguageStat))
+}
+
+// LanguageStatList defines a list of language statistics
+type LanguageStatList []*LanguageStat
+
+// LoadAttributes loads attributes
+func (stats LanguageStatList) LoadAttributes() {
+	for i := range stats {
+		stats[i].Color = enry.GetColor(stats[i].Language)
+	}
+}
+
+func (stats LanguageStatList) getLanguagePercentages() map[string]float32 {
+	langPerc := make(map[string]float32)
+	var otherPerc float32
+	var total int64
+
+	for _, stat := range stats {
+		total += stat.Size
+	}
+	if total > 0 {
+		for _, stat := range stats {
+			perc := float32(float64(stat.Size) / float64(total) * 100)
+			if perc <= 0.1 {
+				otherPerc += perc
+				continue
+			}
+			langPerc[stat.Language] = perc
+		}
+	}
+	if otherPerc > 0 {
+		langPerc["other"] = otherPerc
+	}
+	roundByLargestRemainder(langPerc, 100)
+	return langPerc
+}
+
+// Rounds to 1 decimal point, target should be the expected sum of percs
+func roundByLargestRemainder(percs map[string]float32, target float32) {
+	leftToDistribute := int(target * 10)
+
+	keys := make([]string, 0, len(percs))
+
+	for k, v := range percs {
+		percs[k] = v * 10
+		floored := math.Floor(float64(percs[k]))
+		leftToDistribute -= int(floored)
+		keys = append(keys, k)
+	}
+
+	// Sort the keys by the largest remainder
+	sort.SliceStable(keys, func(i, j int) bool {
+		_, remainderI := math.Modf(float64(percs[keys[i]]))
+		_, remainderJ := math.Modf(float64(percs[keys[j]]))
+		return remainderI > remainderJ
+	})
+
+	// Increment the values in order of largest remainder
+	for _, k := range keys {
+		percs[k] = float32(math.Floor(float64(percs[k])))
+		if leftToDistribute > 0 {
+			percs[k]++
+			leftToDistribute--
+		}
+		percs[k] /= 10
+	}
+}
+
+// GetLanguageStats returns the language statistics for a repository
+func GetLanguageStats(ctx context.Context, repo *Repository) (LanguageStatList, error) {
+	stats := make(LanguageStatList, 0, 6)
+	if err := db.GetEngine(ctx).Where("`repo_id` = ?", repo.ID).Desc("`size`").Find(&stats); err != nil {
+		return nil, err
+	}
+	return stats, nil
+}
+
+// GetTopLanguageStats returns the top language statistics for a repository
+func GetTopLanguageStats(ctx context.Context, repo *Repository, limit int) (LanguageStatList, error) {
+	stats, err := GetLanguageStats(ctx, repo)
+	if err != nil {
+		return nil, err
+	}
+	perc := stats.getLanguagePercentages()
+	topstats := make(LanguageStatList, 0, limit)
+	var other float32
+	for i := range stats {
+		if _, ok := perc[stats[i].Language]; !ok {
+			continue
+		}
+		if stats[i].Language == "other" || len(topstats) >= limit {
+			other += perc[stats[i].Language]
+			continue
+		}
+		stats[i].Percentage = perc[stats[i].Language]
+		topstats = append(topstats, stats[i])
+	}
+	if other > 0 {
+		topstats = append(topstats, &LanguageStat{
+			RepoID:     repo.ID,
+			Language:   "other",
+			Color:      "#cccccc",
+			Percentage: float32(math.Round(float64(other)*10) / 10),
+		})
+	}
+	topstats.LoadAttributes()
+	return topstats, nil
+}
+
+// UpdateLanguageStats updates the language statistics for repository
+func UpdateLanguageStats(ctx context.Context, repo *Repository, commitID string, stats map[string]int64) error {
+	ctx, committer, err := db.TxContext(ctx)
+	if err != nil {
+		return err
+	}
+	defer committer.Close()
+	sess := db.GetEngine(ctx)
+
+	oldstats, err := GetLanguageStats(ctx, repo)
+	if err != nil {
+		return err
+	}
+	var topLang string
+	var s int64
+	for lang, size := range stats {
+		if size > s {
+			s = size
+			topLang = strings.ToLower(lang)
+		}
+	}
+
+	for lang, size := range stats {
+		upd := false
+		llang := strings.ToLower(lang)
+		for _, s := range oldstats {
+			// Update already existing language
+			if strings.ToLower(s.Language) == llang {
+				s.CommitID = commitID
+				s.IsPrimary = llang == topLang
+				s.Size = size
+				if _, err := sess.ID(s.ID).Cols("`commit_id`", "`size`", "`is_primary`").Update(s); err != nil {
+					return err
+				}
+				upd = true
+				break
+			}
+		}
+		// Insert new language
+		if !upd {
+			if err := db.Insert(ctx, &LanguageStat{
+				RepoID:    repo.ID,
+				CommitID:  commitID,
+				IsPrimary: llang == topLang,
+				Language:  lang,
+				Size:      size,
+			}); err != nil {
+				return err
+			}
+		}
+	}
+	// Delete old languages
+	statsToDelete := make([]int64, 0, len(oldstats))
+	for _, s := range oldstats {
+		if s.CommitID != commitID {
+			statsToDelete = append(statsToDelete, s.ID)
+		}
+	}
+	if len(statsToDelete) > 0 {
+		if _, err := sess.In("`id`", statsToDelete).Delete(&LanguageStat{}); err != nil {
+			return err
+		}
+	}
+
+	// Update indexer status
+	if err = UpdateIndexerStatus(ctx, repo, RepoIndexerTypeStats, commitID); err != nil {
+		return err
+	}
+
+	return committer.Commit()
+}
+
+// CopyLanguageStat Copy originalRepo language stat information to destRepo (use for forked repo)
+func CopyLanguageStat(ctx context.Context, originalRepo, destRepo *Repository) error {
+	ctx, committer, err := db.TxContext(ctx)
+	if err != nil {
+		return err
+	}
+	defer committer.Close()
+
+	RepoLang := make(LanguageStatList, 0, 6)
+	if err := db.GetEngine(ctx).Where("`repo_id` = ?", originalRepo.ID).Desc("`size`").Find(&RepoLang); err != nil {
+		return err
+	}
+	if len(RepoLang) > 0 {
+		for i := range RepoLang {
+			RepoLang[i].ID = 0
+			RepoLang[i].RepoID = destRepo.ID
+			RepoLang[i].CreatedUnix = timeutil.TimeStampNow()
+		}
+		// update destRepo's indexer status
+		tmpCommitID := RepoLang[0].CommitID
+		if err := UpdateIndexerStatus(ctx, destRepo, RepoIndexerTypeStats, tmpCommitID); err != nil {
+			return err
+		}
+		if err := db.Insert(ctx, &RepoLang); err != nil {
+			return err
+		}
+	}
+	return committer.Commit()
+}