package fs

import (
	"fmt"
	"runtime"
	"strings"
	"testing"

	"github.com/skeema/skeema/internal/tengo"
)

func TestSQLFileExists(t *testing.T) {
	sf := SQLFile{
		Dir:      "testdata",
		FileName: "statements.sql",
	}
	ok, err := sf.Exists()
	if err != nil {
		t.Errorf("Unexpected error from Exists(): %s", err)
	}
	if !ok {
		t.Errorf("Expected Exists() to return true for %s, but it returned false", sf)
	}
	sf.FileName = "statements2.sql"
	ok, err = sf.Exists()
	if err != nil {
		t.Errorf("Unexpected error from Exists(): %s", err)
	}
	if ok {
		t.Errorf("Expected Exists() to return false for %s, but it returned true", sf)
	}
}

func TestSQLFileCreate(t *testing.T) {
	sf := SQLFile{
		Dir:      "testdata",
		FileName: "statements.sql",
	}
	if err := sf.Create("# hello world"); err == nil {
		t.Error("Expected error from Create() on preexisting file, but err is nil")
	}
	sf.FileName = "statements2.sql"
	if err := sf.Create("# hello world"); err != nil {
		t.Errorf("Unexpected error from Create() on new file: %s", err)
	} else if err := sf.Delete(); err != nil {
		t.Errorf("Unexpected error from Delete(): %s", err)
	}
}

func TestSQLFileTokenizeSuccess(t *testing.T) {
	sf := SQLFile{
		Dir:      "testdata",
		FileName: "statements.sql",
	}
	tokenizedFile, err := sf.Tokenize()
	if err != nil {
		t.Fatalf("Unexpected error from Tokenize(): %v", err)
	}
	expected := expectedStatements(sf.String())
	if len(tokenizedFile.Statements) != len(expected) {
		t.Errorf("Expected %d statements, instead found %d", len(expected), len(tokenizedFile.Statements))
	} else {
		for n := range tokenizedFile.Statements {
			actual, expect := tokenizedFile.Statements[n], expected[n]
			compareStatements(t, n, actual, expect)
			if actual.FromFile != tokenizedFile {
				t.Errorf("statement[%d]: Expected FromFile %p, instead found %p", n, tokenizedFile, actual.FromFile)
			}
		}
	}

	// Test again, this time with CRLF line-ends in the .sql file
	contents := ReadTestFile(t, sf.Path())
	contents = strings.ReplaceAll(contents, "\n", "\r\n")
	sf.FileName = "statements_crlf.sql"
	WriteTestFile(t, sf.Path(), contents)
	defer RemoveTestFile(t, sf.Path())
	tokenizedFile, err = sf.Tokenize()
	if err != nil {
		t.Fatalf("Unexpected error from Tokenize(): %v", err)
	}
	if len(tokenizedFile.Statements) != len(expected) {
		t.Errorf("Expected %d statements, instead found %d", len(expected), len(tokenizedFile.Statements))
	} else {
		for n := range tokenizedFile.Statements {
			actual, expect := tokenizedFile.Statements[n], expected[n]
			expect.File = sf.Path()
			expect.Text = strings.ReplaceAll(expect.Text, "\n", "\r\n")
			expect.nameClause = strings.ReplaceAll(expect.nameClause, "\n", "\r\n")
			compareStatements(t, n, actual, expect)
		}
	}
}

func compareStatements(t *testing.T, n int, actual, expect *Statement) {
	t.Helper()
	if actual.File != expect.File {
		t.Errorf("statement[%d]: Expected file %s, instead found %s", n, expect.File, actual.File)
	}
	if actual.LineNo != expect.LineNo {
		t.Errorf("statement[%d]: Expected line %d, instead found %d", n, expect.LineNo, actual.LineNo)
	}
	if actual.CharNo != expect.CharNo {
		t.Errorf("statement[%d]: Expected char %d, instead found %d", n, expect.CharNo, actual.CharNo)
	}
	if actual.Text != expect.Text {
		t.Errorf("statement[%d]: Expected text %s, instead found %s", n, expect.Text, actual.Text)
	}
	if actual.DefaultDatabase != expect.DefaultDatabase {
		t.Errorf("statement[%d]: Expected default db %s, instead found %s", n, expect.DefaultDatabase, actual.DefaultDatabase)
	}
	if actual.Type != expect.Type {
		t.Errorf("statement[%d]: Expected statement type %d, instead found %d", n, expect.Type, actual.Type)
	}
	if actual.ObjectType != expect.ObjectType {
		t.Errorf("statement[%d]: Expected object type %s, instead found %s", n, expect.ObjectType, actual.ObjectType)
	}
	if actual.ObjectQualifier != expect.ObjectQualifier {
		t.Errorf("statement[%d]: Expected object qualifier %s, instead found %s", n, expect.ObjectQualifier, actual.ObjectQualifier)
	}
	if actual.ObjectName != expect.ObjectName {
		t.Errorf("statement[%d]: Expected object name %s, instead found %s", n, expect.ObjectName, actual.ObjectName)
	}
	if actual.nameClause != expect.nameClause {
		t.Errorf("statement[%d]: Expected name clause %q, instead found %q", n, expect.nameClause, actual.nameClause)
	}
}

func TestSQLFileTokenizeFail(t *testing.T) {
	sf := SQLFile{
		Dir:      "testdata",
		FileName: "statements.sql",
	}
	origContents := ReadTestFile(t, sf.Path())

	// Test error returns for unterminated quote or unterminated C-style comment
	contents := strings.Replace(origContents, "use /*wtf*/`analytics`", "use /*wtf*/`analytics", 1)
	sf2 := SQLFile{
		Dir:      "testdata",
		FileName: "statements2.sql",
	}
	WriteTestFile(t, sf2.Path(), contents)
	if _, err := sf2.Tokenize(); err == nil {
		t.Error("Expected to get an error about unterminated quote, but err was nil")
	}

	contents = strings.Replace(origContents, "use /*wtf*/`analytics`", "use /*wtf`analytics", 1)
	WriteTestFile(t, sf2.Path(), contents)
	if _, err := sf2.Tokenize(); err == nil {
		t.Error("Expected to get an error about unterminated comment, but err was nil")
	}

	// Test error return for nonexistent file
	sf2.Delete()
	if _, err := sf2.Tokenize(); err == nil {
		t.Error("Expected to get an error about nonexistent file, but err was nil")
	}

	// Test handling of files that just contain a single routine definition, but
	// without using the DELIMITER command
	nd1 := SQLFile{
		Dir:      "testdata",
		FileName: "nodelimiter1.sql",
	}
	if tokenizedFile, err := nd1.Tokenize(); err != nil {
		t.Errorf("Unexpected error parsing nodelimiter1.sql: %s", err)
	} else {
		if len(tokenizedFile.Statements) == 2 {
			if tokenizedFile.Statements[0].Type != StatementTypeNoop || tokenizedFile.Statements[1].Type != StatementTypeCreate {
				t.Error("Correct count of statements found, but incorrect types parsed")
			}
		} else {
			t.Errorf("Expected file to contain 2 statements, instead found %d", len(tokenizedFile.Statements))
		}
	}

	// Now try parsing a file that contains a multi-line routine (but no DELIMITER
	// command) followed by another CREATE, and confirm the parsing is "incorrect"
	// in the expected way
	nd2 := SQLFile{
		Dir:      "testdata",
		FileName: "nodelimiter2.sql",
	}
	if tokenizedFile, err := nd2.Tokenize(); err != nil {
		t.Errorf("Unexpected error parsing nodelimiter1.sql: %s", err)
	} else {
		if len(tokenizedFile.Statements) != 8 {
			t.Errorf("Expected file to contain 8 statements, instead found %d", len(tokenizedFile.Statements))
		}
		var seenUnknown bool
		for _, stmt := range tokenizedFile.Statements {
			if stmt.Type == StatementTypeUnknown {
				seenUnknown = true
			}
		}
		if !seenUnknown {
			t.Error("Expected to find a statement that could not be parsed, but did not")
		}
	}
}

func TestTokenizedSQLFileRewrite(t *testing.T) {
	// Use Rewrite() to write file statements2.sql with same contents as statements.sql
	contents := ReadTestFile(t, "testdata/statements.sql")
	sf2 := SQLFile{
		Dir:      "testdata",
		FileName: "statements2.sql",
	}
	tokenizedFile := &TokenizedSQLFile{
		SQLFile:    sf2,
		Statements: expectedStatements(sf2.Path()),
	}
	bytesWritten, err := tokenizedFile.Rewrite()
	if err != nil {
		t.Fatalf("Unexpected error from Rewrite: %s", err)
	}
	contents2 := ReadTestFile(t, sf2.Path())
	if len(contents2) != bytesWritten {
		t.Errorf("Expected bytes written to be %d, instead found %d", len(contents2), bytesWritten)
	}
	if contents2 != contents {
		t.Error("File contents differ from expectation")
	}
	if tokenizedFile, err = sf2.Tokenize(); err != nil {
		t.Fatalf("Unexpected error from Tokenize(): %s", err)
	}

	// Remove everything except commands and whitespace/comments. Rewrite should
	// now delete the file.
	for n := len(tokenizedFile.Statements) - 1; n >= 0; n-- {
		stmt := tokenizedFile.Statements[n]
		if stmt.Type != StatementTypeNoop && stmt.Type != StatementTypeCommand {
			stmt.Remove()
		}
	}
	bytesWritten, err = tokenizedFile.Rewrite()
	if bytesWritten != 0 || err != nil {
		t.Errorf("Unexpected return values from Rewrite: %d / %v", bytesWritten, err)
	}
	if exists, err := sf2.Exists(); exists || err != nil {
		t.Errorf("Unexpected return values from Exists: %t / %v", exists, err)
		sf2.Delete()
	}
}

// expectedStatements returns the expected contents of testdata/statements.sql
// in the form of a slice of statement pointers
func expectedStatements(filePath string) []*Statement {
	return []*Statement{
		{File: filePath, LineNo: 1, CharNo: 1, DefaultDatabase: "", Type: StatementTypeNoop, Text: "  -- this file exists for testing statement tokenization of *.sql files\n\n"},
		{File: filePath, LineNo: 3, CharNo: 1, DefaultDatabase: "", Type: StatementTypeUnknown, Text: "CREATE DATABASE /*!32312 IF NOT EXISTS*/ `product` /*!40100 DEFAULT CHARACTER SET latin1 */;\n"},
		{File: filePath, LineNo: 4, CharNo: 1, DefaultDatabase: "", Type: StatementTypeNoop, Text: "/* hello */   "},
		{File: filePath, LineNo: 4, CharNo: 15, DefaultDatabase: "", Type: StatementTypeCommand, Text: "USE product\n"},
		{File: filePath, LineNo: 5, CharNo: 1, DefaultDatabase: "product", Type: StatementTypeNoop, Text: "\n"},
		{File: filePath, LineNo: 6, CharNo: 1, DefaultDatabase: "product", Type: StatementTypeCreate, ObjectType: tengo.ObjectTypeTable, ObjectName: "users", Text: "CREATE #fun interruption\nTABLE `users` (\n  `id` bigint(20) unsigned NOT NULL AUTO_INCREMENT,\n  `na``me` varchar(30) NOT NULL DEFAULT 'it\\'s complicated \"escapes''',--\tend of line comment with tab\n  `credits` decimal(9,2) DEFAULT '10.00', --\u3000end of line; \" comment with ideographic space\n  `last_modified` timestamp NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP, # another end-of-line comment;\n  PRIMARY KEY (`id`),\n  UNIQUE KEY `name` (`name`)\n) ENGINE=InnoDB DEFAULT CHARSET=latin1;\n", nameClause: "`users` "},
		{File: filePath, LineNo: 15, CharNo: 1, DefaultDatabase: "product", Type: StatementTypeNoop, Text: "          "},
		{File: filePath, LineNo: 15, CharNo: 11, DefaultDatabase: "product", Type: StatementTypeCreate, ObjectType: tengo.ObjectTypeTable, ObjectName: "posts with spaces", Text: "CREATE TABLE `posts with spaces` (\n  `id` bigint(20) unsigned NOT NULL AUTO_INCREMENT,\n  `user_id` bigint(20) unsigned NOT NULL,\n  `body` varchar(50) DEFAULT '/* lol\\'',\n  `created_at` datetime /*!50601 DEFAULT CURRENT_TIMESTAMP*/,\n  `edited_at` datetime /*!50601 DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP*/,\n  PRIMARY KEY (`id`),\n  KEY `user_created` (`user_id`,`created_at`)\n) ENGINE=InnoDB DEFAULT CHARSET=latin1;\n", nameClause: "`posts with spaces` "},
		{File: filePath, LineNo: 24, CharNo: 1, DefaultDatabase: "product", Type: StatementTypeNoop, Text: "\n\n--\n"},
		{File: filePath, LineNo: 27, CharNo: 1, DefaultDatabase: "product", Type: StatementTypeCreate, ObjectType: tengo.ObjectTypeFunc, ObjectName: "funcnodefiner", Text: "create function funcnodefiner() RETURNS varchar(30) RETURN \"hello\";\n", nameClause: "funcnodefiner"},
		{File: filePath, LineNo: 28, CharNo: 1, DefaultDatabase: "product", Type: StatementTypeCreate, ObjectType: tengo.ObjectTypeFunc, ObjectName: "funccuruserparens", Text: "CREATE DEFINER = CURRENT_USER() FUNCTION funccuruserparens() RETURNS int RETURN 42;\n", nameClause: "funccuruserparens"},
		{File: filePath, LineNo: 29, CharNo: 1, DefaultDatabase: "product", Type: StatementTypeCreate, ObjectType: tengo.ObjectTypeProc, ObjectName: "proccurusernoparens", Text: "CREATE DEFINER=CURRENT_USER PROCEDURE proccurusernoparens() # this is a comment!\n\tSELECT 1;\n", nameClause: "proccurusernoparens"},
		{File: filePath, LineNo: 31, CharNo: 1, DefaultDatabase: "product", Type: StatementTypeCreate, ObjectType: tengo.ObjectTypeFunc, ObjectName: "funcdefquote2", ObjectQualifier: "analytics", Text: "create definer=foo@'localhost' /*lol*/ FUNCTION analytics.funcdefquote2() RETURNS int RETURN 42;\n", nameClause: "analytics.funcdefquote2"},
		{File: filePath, LineNo: 32, CharNo: 1, DefaultDatabase: "product", Type: StatementTypeCreate, ObjectType: tengo.ObjectTypeProc, ObjectName: "procdefquote1", Text: "create DEFINER = 'foo'@localhost PROCEDURE `procdefquote1`() SELECT 42;\n", nameClause: "`procdefquote1`"},
		{File: filePath, LineNo: 33, CharNo: 1, DefaultDatabase: "product", Type: StatementTypeNoop, Text: "\t"},
		{File: filePath, LineNo: 33, CharNo: 2, DefaultDatabase: "product", Type: StatementTypeCommand, Text: "delimiter    \"💩💩💩\"\n"},
		{File: filePath, LineNo: 34, CharNo: 1, DefaultDatabase: "product", Type: StatementTypeCreate, ObjectType: tengo.ObjectTypeTable, ObjectName: "uhoh", Text: "CREATE TABLE uhoh (ummm varchar(20) default 'ok 💩💩💩 cool')💩💩💩\n", nameClause: "uhoh "},
		{File: filePath, LineNo: 35, CharNo: 1, DefaultDatabase: "product", Type: StatementTypeCommand, Text: "DELIMITER //\n"},
		{File: filePath, LineNo: 36, CharNo: 1, DefaultDatabase: "product", Type: StatementTypeCreate, ObjectType: tengo.ObjectTypeProc, ObjectName: "whatever", Text: "CREATE PROCEDURE whatever(name varchar(10))\nBEGIN\n\tDECLARE v1 INT; -- comment with \"normal space\" in front!\n\tSET v1=loops;--\u00A0comment with `nbsp' in front?!?\n\tWHILE v1 > 0 DO\n\t\tINSERT INTO users (name) values ('\\xF0\\x9D\\x8C\\x86');\n\t\tSET v1 = v1 - (2 / 2); /* testing // testing */\n\tEND WHILE;\nEND\n//\n", nameClause: "whatever"},
		{File: filePath, LineNo: 46, CharNo: 1, DefaultDatabase: "product", Type: StatementTypeCommand, Text: "delimiter ;\n"},
		{File: filePath, LineNo: 47, CharNo: 1, DefaultDatabase: "product", Type: StatementTypeNoop, Text: "\n"},
		{File: filePath, LineNo: 48, CharNo: 1, DefaultDatabase: "product", Type: StatementTypeCreate, ObjectType: tengo.ObjectTypeTable, ObjectName: "tbl1", ObjectQualifier: "uhoh", Text: "CREATE TABLE `uhoh` . tbl1 (id int unsigned not null primary key);\n", nameClause: "`uhoh` . tbl1 "},
		{File: filePath, LineNo: 49, CharNo: 1, DefaultDatabase: "product", Type: StatementTypeCreate, ObjectType: tengo.ObjectTypeTable, ObjectName: "tbl2", ObjectQualifier: "uhoh", Text: "CREATE TABLE uhoh.tbl2 (id int unsigned not null primary key);\n", nameClause: "uhoh.tbl2 "},
		{File: filePath, LineNo: 50, CharNo: 1, DefaultDatabase: "product", Type: StatementTypeCreate, ObjectType: tengo.ObjectTypeTable, ObjectName: "tbl3", ObjectQualifier: "uhoh", Text: "CREATE TABLE /*lol*/ uhoh  .  `tbl3` (id int unsigned not null primary key);\n", nameClause: "uhoh  .  `tbl3` "},
		{File: filePath, LineNo: 51, CharNo: 1, DefaultDatabase: "product", Type: StatementTypeCreate, ObjectType: tengo.ObjectTypeFunc, ObjectName: "funcdefquote3", ObjectQualifier: "foo", Text: "create definer=foo@'localhost' /*lol*/ FUNCTION foo.funcdefquote3() RETURNS int RETURN 42;\n", nameClause: "foo.funcdefquote3"},
		{File: filePath, LineNo: 52, CharNo: 1, DefaultDatabase: "product", Type: StatementTypeNoop, Text: "\n"},
		{File: filePath, LineNo: 53, CharNo: 1, DefaultDatabase: "product", Type: StatementTypeCommand, Text: "use /*wtf*/`analytics`;"},
		{File: filePath, LineNo: 53, CharNo: 24, DefaultDatabase: "analytics", Type: StatementTypeCreate, ObjectType: tengo.ObjectTypeTable, ObjectName: "comments", Text: "CREATE TABLE  if  NOT    eXiStS     `comments` (\n  `id` bigint(20) unsigned NOT NULL AUTO_INCREMENT,\n  `post_id` bigint(20) unsigned NOT NULL,\n  `user_id` bigint(20) unsigned NOT NULL,\n  `created_at` datetime DEFAULT NULL,\n  `body` text,\n  PRIMARY KEY (`id`)\n) ENGINE=InnoDB DEFAULT CHARSET=latin1;\n", nameClause: "`comments` "},
		{File: filePath, LineNo: 61, CharNo: 1, DefaultDatabase: "analytics", Type: StatementTypeCreate, ObjectType: tengo.ObjectTypeTable, ObjectName: "subscriptions", Text: "CREATE TABLE subscriptions (id int unsigned not null primary key)", nameClause: "subscriptions "},
	}
}

func TestPathForObject(t *testing.T) {
	cases := []struct {
		DirPath    string
		ObjectName string
		Expected   string
	}{
		{"", "foobar", "foobar.sql"},
		{"/foo/bar", "baz", "/foo/bar/baz.sql"},
		{"/var/schemas", "", "/var/schemas/symbols.sql"},
		{"/var/schemas", "[*]. ({`'\"})", "/var/schemas/symbols.sql"},
		{"/var/schemas", "foo_bar", "/var/schemas/foo_bar.sql"},
		{"/var/schemas", "foo-bar", "/var/schemas/foobar.sql"},
		{"/var/schemas", "../../etc/passwd", "/var/schemas/etcpasswd.sql"},
	}
	for _, c := range cases {
		if runtime.GOOS == "windows" {
			if c.DirPath != "" {
				c.DirPath = fmt.Sprintf("C:%s", strings.ReplaceAll(c.DirPath, "/", "\\"))
				c.Expected = fmt.Sprintf("C:%s", strings.ReplaceAll(c.Expected, "/", "\\"))
			}
		}
		if actual := PathForObject(c.DirPath, c.ObjectName); actual != c.Expected {
			t.Errorf("Expected PathForObject(%q, %q) to return %q, instead found %q", c.DirPath, c.ObjectName, c.Expected, actual)
		}
	}
}

func TestAppendToFile(t *testing.T) {
	assertAppend := func(filePath, contents string, expectBytes int, expectCreated bool) {
		t.Helper()
		bytesWritten, created, err := AppendToFile(filePath, contents)
		if err != nil {
			t.Errorf("Unexpected error from AppendToFile on %s: %s", filePath, err)
		}
		if bytesWritten != expectBytes {
			t.Errorf("Incorrect bytes-written from AppendToFile: expected %d, found %d", expectBytes, bytesWritten)
		}
		if created != expectCreated {
			t.Error("created did not match expectation")
		}
	}

	WriteTestFile(t, "testdata/.scratch/append-test1", "")
	assertAppend("testdata/.scratch/append-test1", "hello world", 11, false)
	assertAppend("testdata/.scratch/append-test2", "hello world", 11, true)
	assertAppend("testdata/.scratch/append-test2", "hello world", 23, false)
	if contents := ReadTestFile(t, "testdata/.scratch/append-test2"); contents != "hello world\nhello world" {
		t.Errorf("Unexpected contents: %s", contents)
	}
	RemoveTestFile(t, "testdata/.scratch/append-test1")
	RemoveTestFile(t, "testdata/.scratch/append-test2")
	RemoveTestFile(t, "testdata/.scratch")
}

func TestAddDelimiter(t *testing.T) {
	proc := `CREATE PROCEDURE whatever(name varchar(10))
BEGIN
	DECLARE v1 INT;
	SET v1=loops;
	WHILE v1 > 0 DO
		INSERT INTO users (name) values ('\xF0\x9D\x8C\x86');
		SET v1 = v1 - (2 / 2); /* testing // testing */
	END WHILE;
END;`
	result := AddDelimiter(proc)
	if result == proc || !strings.Contains(result, "DELIMITER") {
		t.Errorf("Unexpected result from AddDelimiter: %s", result)
	}

	proc = `CREATE FUNCTION foo() RETURNS varchar(30) RETURN "hello"`
	result = AddDelimiter(proc)
	if result == proc || strings.Contains(result, "DELIMITER") || !strings.HasSuffix(result, ";\n") {
		t.Errorf("Unexpected result from AddDelimiter: %s", result)
	}
}
