From 87c55fbcafc126e21ab4bda02918437af1cf0965 Mon Sep 17 00:00:00 2001
From: Drew DeVault <sir@cmpwn.com>
Date: Tue, 5 May 2020 17:35:35 -0400
Subject: [PATCH] API: More progress on working cursors

---
 api/database/sq.go            |  1 -
 api/graph/model/cursor.go     | 11 +++++++++++
 api/graph/model/repository.go | 16 +++++++++++++++-
 api/graph/schema.resolvers.go | 15 ++++++++++++---
 4 files changed, 38 insertions(+), 5 deletions(-)

diff --git a/api/database/sq.go b/api/database/sq.go
index 82c8a2b..22b2558 100644
--- a/api/database/sq.go
+++ b/api/database/sq.go
@@ -8,7 +8,6 @@ import (
 )
 
 type Selectable interface {
-	As(alias string) Selectable
 	Select(ctx context.Context) []string
 	Fields(ctx context.Context) []interface{}
 }
diff --git a/api/graph/model/cursor.go b/api/graph/model/cursor.go
index 4a8955c..d6108b1 100644
--- a/api/graph/model/cursor.go
+++ b/api/graph/model/cursor.go
@@ -8,6 +8,7 @@ import (
 	"git.sr.ht/~sircmpwn/git.sr.ht/api/crypto"
 )
 
+// TODO: Add a field for the resource this is intended to be used with
 type Cursor struct {
 	Count   int    `json:"count"`
 	Next    string `json:"next"`
@@ -41,3 +42,13 @@ func (cur Cursor) MarshalGQL(w io.Writer) {
 	w.Write(crypto.Encrypt(data))
 	w.Write([]byte("\""))
 }
+
+func NewCursor(filter *Filter) *Cursor {
+	// TODO: Apply filter
+	return &Cursor{
+		Count:   25,
+		Next:    "",
+		OrderBy: "",
+		Search:  "",
+	}
+}
diff --git a/api/graph/model/repository.go b/api/graph/model/repository.go
index 501a4fe..86a8247 100644
--- a/api/graph/model/repository.go
+++ b/api/graph/model/repository.go
@@ -3,6 +3,7 @@ package model
 import (
 	"context"
 	"time"
+	"strconv"
 
 	"github.com/go-git/go-git/v5"
 	sq "github.com/Masterminds/squirrel"
@@ -66,7 +67,7 @@ func (r *Repository) Select(ctx context.Context) []string {
 		database.WithAlias(r.alias, "owner_id"))
 }
 
-func (r *Repository) As(alias string) database.Selectable {
+func (r *Repository) As(alias string) *Repository {
 	r.alias = alias
 	return r
 }
@@ -84,6 +85,19 @@ func (r *Repository) Fields(ctx context.Context) []interface{} {
 	return append(fields, &r.Path, &r.OwnerID)
 }
 
+func (r *Repository) ApplyCursor(q sq.SelectBuilder, c *Cursor) sq.SelectBuilder {
+	if c.Next != "" {
+		id, _ := strconv.Atoi(c.Next)
+		q = q.Where(r.alias + `.id <= ?`, id)
+	}
+	if c.OrderBy != "" {
+		q = q.OrderBy(c.OrderBy)
+	} else {
+		q = q.OrderBy(r.alias + `.id DESC`)
+	}
+	return q.Limit(uint64(c.Count + 1))
+}
+
 func (r *Repository) DefaultSearch(query sq.SelectBuilder,
 	term string) (sq.SelectBuilder, error) {
 	name := database.WithAlias(r.alias, "name")
diff --git a/api/graph/schema.resolvers.go b/api/graph/schema.resolvers.go
index 357aa06..9c4d271 100644
--- a/api/graph/schema.resolvers.go
+++ b/api/graph/schema.resolvers.go
@@ -160,17 +160,22 @@ func (r *userResolver) Repositories(ctx context.Context, obj *model.User, cursor
 		err  error
 		rows *sql.Rows
 	)
+
 	repo := (&model.Repository{}).As(`repo`)
 	query := database.
 		Select(ctx, repo).
 		From(`repository repo`).
-		Where(`repo.owner_id = ?`, obj.ID).
-		OrderBy(`id DESC`).
-		Limit(26)
+		Where(`repo.owner_id = ?`, obj.ID)
+	if cursor == nil {
+		cursor = model.NewCursor(filter)
+	}
+	query = repo.ApplyCursor(query, cursor)
+
 	if rows, err = query.RunWith(r.DB).QueryContext(ctx); err != nil {
 		panic(err)
 	}
 	defer rows.Close()
+
 	var repos []*model.Repository
 	for rows.Next() {
 		var repo model.Repository
@@ -179,6 +184,7 @@ func (r *userResolver) Repositories(ctx context.Context, obj *model.User, cursor
 		}
 		repos = append(repos, &repo)
 	}
+
 	if len(repos) > 25 {
 		cursor = &model.Cursor{
 			Count:   25,
@@ -187,7 +193,10 @@ func (r *userResolver) Repositories(ctx context.Context, obj *model.User, cursor
 			Search:  "",
 		}
 		repos = repos[:25]
+	} else {
+		cursor = nil
 	}
+
 	return &model.RepositoryCursor{repos, cursor}, nil
 }
 
-- 
2.38.4