/*
    *    Copyright 2010-2023 the original author or authors.
    *
    *    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
    *
    *       https://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 org.apache.ibatis.migration.operations;
  
  import java.io.PrintStream;
  import java.io.Reader;
  import java.sql.Connection;
  import java.util.Collections;
  import java.util.HashMap;
  import java.util.List;
  import java.util.Map;
  
  import org.apache.ibatis.migration.Change;
  import org.apache.ibatis.migration.ConnectionProvider;
  import org.apache.ibatis.migration.MigrationException;
  import org.apache.ibatis.migration.MigrationLoader;
  import org.apache.ibatis.migration.hook.HookContext;
  import org.apache.ibatis.migration.hook.MigrationHook;
  import org.apache.ibatis.migration.options.DatabaseOperationOption;
  import org.apache.ibatis.migration.utils.Util;
  
  public final class UpOperation extends DatabaseOperation {
    private final Integer steps;
  
    public UpOperation() {
      this.steps = null;
    }
  
    public UpOperation(Integer steps) {
      this.steps = steps;
      if (steps != null && steps.intValue() < 1) {
        throw new IllegalArgumentException("step must be positive number or null.");
      }
    }
  
    public UpOperation operate(ConnectionProvider connectionProvider, MigrationLoader migrationsLoader,
        DatabaseOperationOption option, PrintStream printStream) {
      return operate(connectionProvider, migrationsLoader, option, printStream, null);
    }
  
    public UpOperation operate(ConnectionProvider connectionProvider, MigrationLoader migrationsLoader,
        DatabaseOperationOption option, PrintStream printStream, MigrationHook hook) {
      try (Connection con = connectionProvider.getConnection()) {
        if (option == null) {
          option = new DatabaseOperationOption();
        }
  
        List<Change> changesInDb = Collections.emptyList();
        if (changelogExists(con, option)) {
          changesInDb = getChangelog(con, option);
        }
  
        List<Change> migrations = migrationsLoader.getMigrations();
        Collections.sort(migrations);
        String skippedOrMissing = checkSkippedOrMissing(changesInDb, migrations);
        int stepCount = 0;
  
        Map<String, Object> hookBindings = new HashMap<>();
        ScriptRunner runner = getScriptRunner(con, option, printStream);
        try {
          for (Change change : migrations) {
            if (changesInDb.isEmpty() || change.compareTo(changesInDb.get(changesInDb.size() - 1)) > 0) {
              if (stepCount == 0 && hook != null) {
                hookBindings.put(MigrationHook.HOOK_CONTEXT, new HookContext(connectionProvider, runner, null));
                hook.before(hookBindings);
              }
              if (hook != null) {
                hookBindings.put(MigrationHook.HOOK_CONTEXT,
                    new HookContext(connectionProvider, runner, new Change(change)));
                hook.beforeEach(hookBindings);
              }
              println(printStream, Util.horizontalLine("Applying: " + change.getFilename(), 80));
              try (Reader scriptReader = migrationsLoader.getScriptReader(change, false)) {
                runner.runScript(scriptReader);
              }
              insertChangelog(change, con, option);
              println(printStream);
              if (hook != null) {
                hookBindings.put(MigrationHook.HOOK_CONTEXT,
                    new HookContext(connectionProvider, runner, new Change(change)));
                hook.afterEach(hookBindings);
              }
              stepCount++;
              if (steps != null && stepCount >= steps) {
                break;
              }
           }
         }
         if (stepCount > 0 && hook != null) {
           hookBindings.put(MigrationHook.HOOK_CONTEXT, new HookContext(connectionProvider, runner, null));
           hook.after(hookBindings);
         }
         println(printStream, skippedOrMissing);
         return this;
       } catch (Exception e) {
         try (Reader onAbortScriptReader = migrationsLoader.getOnAbortReader()) {
           if (onAbortScriptReader != null) {
             println(printStream);
             println(printStream, Util.horizontalLine("Executing onabort.sql script.", 80));
             runner.runScript(onAbortScriptReader);
             println(printStream);
           }
         }
         throw e;
       }
     } catch (Throwable e) {
       while (e instanceof MigrationException && e.getCause() != null) {
         e = e.getCause();
       }
       throw new MigrationException("Error executing command.  Cause: " + e, e);
     }
   }
 }