// Copyright 2025 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package tidb

import (
	"context"
	"database/sql"
	"fmt"
	"os"
	"regexp"
	"strings"
	"testing"
	"time"

	"github.com/google/uuid"
	"github.com/googleapis/genai-toolbox/internal/testutils"
	"github.com/googleapis/genai-toolbox/tests"
)

var (
	TiDBSourceKind = "tidb"
	TiDBToolKind   = "tidb-sql"
	TiDBDatabase   = os.Getenv("TIDB_DATABASE")
	TiDBHost       = os.Getenv("TIDB_HOST")
	TiDBPort       = os.Getenv("TIDB_PORT")
	TiDBUser       = os.Getenv("TIDB_USER")
	TiDBPass       = os.Getenv("TIDB_PASS")
)

func getTiDBVars(t *testing.T) map[string]any {
	switch "" {
	case TiDBDatabase:
		t.Fatal("'TIDB_DATABASE' not set")
	case TiDBHost:
		t.Fatal("'TIDB_HOST' not set")
	case TiDBPort:
		t.Fatal("'TIDB_PORT' not set")
	case TiDBUser:
		t.Fatal("'TIDB_USER' not set")
	case TiDBPass:
		t.Fatal("'TIDB_PASS' not set")
	}

	return map[string]any{
		"kind":     TiDBSourceKind,
		"host":     TiDBHost,
		"port":     TiDBPort,
		"database": TiDBDatabase,
		"user":     TiDBUser,
		"password": TiDBPass,
	}
}

// Copied over from tidb.go
func initTiDBConnectionPool(host, port, user, pass, dbname string, useSSL bool) (*sql.DB, error) {
	dsn := fmt.Sprintf("%s:%s@tcp(%s:%s)/%s?parseTime=true&charset=utf8mb4&tls=%t", user, pass, host, port, dbname, useSSL)

	// Interact with the driver directly as you normally would
	pool, err := sql.Open("mysql", dsn)
	if err != nil {
		return nil, fmt.Errorf("sql.Open: %w", err)
	}
	return pool, nil
}

// getTiDBWants return the expected wants for tidb
func getTiDBWants() (string, string, string, string) {
	select1Want := "[{\"1\":1}]"
	mcpMyFailToolWant := `{"jsonrpc":"2.0","id":"invoke-fail-tool","result":{"content":[{"type":"text","text":"unable to execute query: Error 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your TiDB version for the right syntax to use line 1 column 5 near \"SELEC 1;\" "}],"isError":true}}`
	createTableStatement := `"CREATE TABLE t (id SERIAL PRIMARY KEY, name TEXT)"`
	mcpSelect1Want := `{"jsonrpc":"2.0","id":"invoke my-auth-required-tool","result":{"content":[{"type":"text","text":"{\"1\":1}"}]}}`
	return select1Want, mcpMyFailToolWant, createTableStatement, mcpSelect1Want
}

// addTiDBExecuteSqlConfig gets the tools config for `tidb-execute-sql`
func addTiDBExecuteSqlConfig(t *testing.T, config map[string]any) map[string]any {
	tools, ok := config["tools"].(map[string]any)
	if !ok {
		t.Fatalf("unable to get tools from config")
	}
	tools["my-exec-sql-tool"] = map[string]any{
		"kind":        "tidb-execute-sql",
		"source":      "my-instance",
		"description": "Tool to execute sql",
	}
	tools["my-auth-exec-sql-tool"] = map[string]any{
		"kind":        "tidb-execute-sql",
		"source":      "my-instance",
		"description": "Tool to execute sql",
		"authRequired": []string{
			"my-google-auth",
		},
	}
	config["tools"] = tools
	return config
}

func TestTiDBToolEndpoints(t *testing.T) {
	sourceConfig := getTiDBVars(t)
	ctx, cancel := context.WithTimeout(context.Background(), time.Minute)
	defer cancel()

	var args []string

	pool, err := initTiDBConnectionPool(TiDBHost, TiDBPort, TiDBUser, TiDBPass, TiDBDatabase, false)
	if err != nil {
		t.Fatalf("unable to create TiDB connection pool: %s", err)
	}

	// create table name with UUID
	tableNameParam := "param_table_" + strings.ReplaceAll(uuid.New().String(), "-", "")
	tableNameAuth := "auth_table_" + strings.ReplaceAll(uuid.New().String(), "-", "")
	tableNameTemplateParam := "template_param_table_" + strings.ReplaceAll(uuid.New().String(), "-", "")

	// set up data for param tool
	createParamTableStmt, insertParamTableStmt, paramToolStmt, idParamToolStmt, nameParamToolStmt, arrayToolStmt, paramTestParams := tests.GetMySQLParamToolInfo(tableNameParam)
	teardownTable1 := tests.SetupMySQLTable(t, ctx, pool, createParamTableStmt, insertParamTableStmt, tableNameParam, paramTestParams)
	defer teardownTable1(t)

	// set up data for auth tool
	createAuthTableStmt, insertAuthTableStmt, authToolStmt, authTestParams := tests.GetMySQLAuthToolInfo(tableNameAuth)
	teardownTable2 := tests.SetupMySQLTable(t, ctx, pool, createAuthTableStmt, insertAuthTableStmt, tableNameAuth, authTestParams)
	defer teardownTable2(t)

	// Write config into a file and pass it to command
	toolsFile := tests.GetToolsConfig(sourceConfig, TiDBToolKind, paramToolStmt, idParamToolStmt, nameParamToolStmt, arrayToolStmt, authToolStmt)
	toolsFile = addTiDBExecuteSqlConfig(t, toolsFile)
	tmplSelectCombined, tmplSelectFilterCombined := tests.GetMySQLTmplToolStatement()
	toolsFile = tests.AddTemplateParamConfig(t, toolsFile, TiDBToolKind, tmplSelectCombined, tmplSelectFilterCombined, "")

	cmd, cleanup, err := tests.StartCmd(ctx, toolsFile, args...)
	if err != nil {
		t.Fatalf("command initialization returned an error: %s", err)
	}
	defer cleanup()

	waitCtx, cancel := context.WithTimeout(ctx, 10*time.Second)
	defer cancel()
	out, err := testutils.WaitForString(waitCtx, regexp.MustCompile(`Server ready to serve`), cmd.Out)
	if err != nil {
		t.Logf("toolbox command logs: \n%s", out)
		t.Fatalf("toolbox didn't start successfully: %s", err)
	}

	// Get configs for tests
	select1Want, mcpMyFailToolWant, createTableStatement, mcpSelect1Want := getTiDBWants()

	// Run tests
	tests.RunToolGetTest(t)
	tests.RunToolInvokeTest(t, select1Want, tests.DisableArrayTest())
	tests.RunMCPToolCallMethod(t, mcpMyFailToolWant, mcpSelect1Want)
	tests.RunExecuteSqlToolInvokeTest(t, createTableStatement, select1Want)
	tests.RunToolInvokeWithTemplateParameters(t, tableNameTemplateParam)
}
