From 2575ccbb68b60dfe3da86e425db60a3956e5abaf Mon Sep 17 00:00:00 2001
From: k1LoW <k1lowxb@gmail.com>
Date: Mon, 6 Aug 2018 22:45:55 +0900
Subject: [PATCH] Support CHECK constraints

---
 drivers/sqlite/sqlite.go           | 46 +++++++++++++++++++++++++++++-
 drivers/sqlite/sqlite_test.go      |  2 +-
 output/md/templates.go             | 12 ++++----
 sample/sqlite/check_constraints.md |  5 ++++
 sample/sqlite/users.md             |  1 +
 5 files changed, 58 insertions(+), 8 deletions(-)

diff --git a/drivers/sqlite/sqlite.go b/drivers/sqlite/sqlite.go
index da73c94c..8f35b145 100644
--- a/drivers/sqlite/sqlite.go
+++ b/drivers/sqlite/sqlite.go
@@ -8,6 +8,7 @@ import (
 
 	"github.com/k1LoW/tbls/schema"
 	"github.com/pkg/errors"
+	"regexp"
 )
 
 // Sqlite struct
@@ -311,7 +312,50 @@ func convertColumnNullable(str string) bool {
 }
 
 func parseCheckConstraints(sql string) []*schema.Constraint {
-	// TODO
+	// tokenize
+	re := regexp.MustCompile(`\s+`)
+	separator := "__SEP__"
+	space := "__SP__"
+	r1 := strings.NewReplacer("(", fmt.Sprintf("%s(%s", separator, separator), ")", fmt.Sprintf("%s)%s", separator, separator), ",", fmt.Sprintf("%s,%s", separator, separator))
+	r2 := strings.NewReplacer(" ", fmt.Sprintf("%s%s%s", separator, space, separator))
+	tokens := strings.Split(r1.Replace(r2.Replace(re.ReplaceAllString(sql, " "))), separator)
+
+	r3 := strings.NewReplacer(space, " ")
 	constraints := []*schema.Constraint{}
+	def := ""
+	counter := 0
+	for _, v := range tokens {
+		if counter == 0 && (v == "CHECK" || v == "check") {
+			def = v
+			continue
+		}
+		if def != "" && v == space {
+			def = def + v
+			continue
+		}
+		if def != "" && v == "(" {
+			def = def + v
+			counter = counter + 1
+			continue
+		}
+		if def != "" && v == ")" {
+			def = def + v
+			counter = counter - 1
+			if counter == 0 {
+				constraint := &schema.Constraint{
+					Name: "-",
+					Type: "CHECK",
+					Def:  r3.Replace(def),
+				}
+				constraints = append(constraints, constraint)
+				def = ""
+			}
+			continue
+		}
+		if def != "" && counter > 0 {
+			def = def + v
+		}
+	}
+
 	return constraints
 }
diff --git a/drivers/sqlite/sqlite_test.go b/drivers/sqlite/sqlite_test.go
index 1120da8b..09b6bc0d 100644
--- a/drivers/sqlite/sqlite_test.go
+++ b/drivers/sqlite/sqlite_test.go
@@ -84,6 +84,6 @@ func TestParseCheckConstraints(t *testing.T) {
 	}
 	actual := parseCheckConstraints(sql)
 	if !reflect.DeepEqual(actual, expected) {
-		t.Errorf("got: %v\nwant: %v", actual, expected)
+		t.Errorf("got: %#v\nwant: %#v", actual, expected)
 	}
 }
diff --git a/output/md/templates.go b/output/md/templates.go
index afcf1d99..02a20cae 100644
--- a/output/md/templates.go
+++ b/output/md/templates.go
@@ -11,7 +11,12 @@ var _Assetsac44302fb6150a621aa9d04a0350aac972bf7e18 = "# {{ .Table.Name }}\n\n##
 
 // Assets returns go-assets FileSystem
 var Assets = assets.NewFileSystem(map[string][]string{"/": []string{"index.md.tmpl", "table.md.tmpl"}}, map[string]*assets.File{
-	"/index.md.tmpl": &assets.File{
+	"/": &assets.File{
+		Path:     "/",
+		FileMode: 0x800001ed,
+		Mtime:    time.Unix(1532785399, 1532785399000000000),
+		Data:     nil,
+	}, "/index.md.tmpl": &assets.File{
 		Path:     "/index.md.tmpl",
 		FileMode: 0x1a4,
 		Mtime:    time.Unix(1532239511, 1532239511000000000),
@@ -21,9 +26,4 @@ var Assets = assets.NewFileSystem(map[string][]string{"/": []string{"index.md.tm
 		FileMode: 0x1a4,
 		Mtime:    time.Unix(1532785399, 1532785399000000000),
 		Data:     []byte(_Assetsac44302fb6150a621aa9d04a0350aac972bf7e18),
-	}, "/": &assets.File{
-		Path:     "/",
-		FileMode: 0x800001ed,
-		Mtime:    time.Unix(1532785399, 1532785399000000000),
-		Data:     nil,
 	}}, "")
diff --git a/sample/sqlite/check_constraints.md b/sample/sqlite/check_constraints.md
index e6cb5459..00a2c481 100644
--- a/sample/sqlite/check_constraints.md
+++ b/sample/sqlite/check_constraints.md
@@ -42,6 +42,11 @@ CREATE TABLE check_constraints (
 | sqlite_autoindex_check_constraints_3 | UNIQUE | UNIQUE (downcase) |
 | sqlite_autoindex_check_constraints_2 | UNIQUE | UNIQUE (checkcheck) |
 | sqlite_autoindex_check_constraints_1 | UNIQUE | UNIQUE (brackets) |
+| - | CHECK | CHECK(length(col) > 4) |
+| - | CHECK | CHECK(((length(brackets) > 4))) |
+| - | CHECK | CHECK(length(checkcheck) > 4) |
+| - | CHECK | check(length(downcase) > 4) |
+| - | CHECK | check(length(nl) > 4 OR nl != 'ln') |
 
 ## Indexes
 
diff --git a/sample/sqlite/users.md b/sample/sqlite/users.md
index d24ba3d3..41ac3ada 100644
--- a/sample/sqlite/users.md
+++ b/sample/sqlite/users.md
@@ -38,6 +38,7 @@ CREATE TABLE users (
 | id | PRIMARY KEY | PRIMARY KEY (id) |
 | sqlite_autoindex_users_2 | UNIQUE | UNIQUE (email) |
 | sqlite_autoindex_users_1 | UNIQUE | UNIQUE (username) |
+| - | CHECK | CHECK(length(username) > 4) |
 
 ## Indexes