require “active_record”

databases = ActiveRecord::Tasks::DatabaseTasks#setup_initial_database_yaml

db_namespace = namespace :db do

desc "Set the environment value for the database"
task "environment:set" => :load_config do
  ActiveRecord::InternalMetadata.create_table
  ActiveRecord::InternalMetadata[:environment] = ActiveRecord::Base.connection.migration_context.current_environment
end

task check_protected_environments: :load_config do
  ActiveRecord::Tasks::DatabaseTasks.check_protected_environments!
end

task load_config: :environment do
  ActiveRecord::Base.configurations       = ActiveRecord::Tasks::DatabaseTasks.database_configuration || {}
  ActiveRecord::Migrator.migrations_paths = ActiveRecord::Tasks::DatabaseTasks.migrations_paths
end

namespace :create do
  task all: :load_config do
    ActiveRecord::Tasks::DatabaseTasks.create_all
  end

  ActiveRecord::Tasks::DatabaseTasks.for_each(databases) do |spec_name|
    desc "Create #{spec_name} database for current environment"
    task spec_name => :load_config do
      db_config = ActiveRecord::Base.configurations.configs_for(env_name: Rails.env, spec_name: spec_name)
      ActiveRecord::Tasks::DatabaseTasks.create(db_config.config)
    end
  end
end

desc "Creates the database from DATABASE_URL or config/database.yml for the current RAILS_ENV (use db:create:all to create all databases in the config). Without RAILS_ENV or when RAILS_ENV is development, it defaults to creating the development and test databases."
task create: [:load_config] do
  ActiveRecord::Tasks::DatabaseTasks.create_current
end

namespace :drop do
  task all: [:load_config, :check_protected_environments] do
    ActiveRecord::Tasks::DatabaseTasks.drop_all
  end

  ActiveRecord::Tasks::DatabaseTasks.for_each(databases) do |spec_name|
    desc "Drop #{spec_name} database for current environment"
    task spec_name => [:load_config, :check_protected_environments] do
      db_config = ActiveRecord::Base.configurations.configs_for(env_name: Rails.env, spec_name: spec_name)
      ActiveRecord::Tasks::DatabaseTasks.drop(db_config.config)
    end
  end
end

desc "Drops the database from DATABASE_URL or config/database.yml for the current RAILS_ENV (use db:drop:all to drop all databases in the config). Without RAILS_ENV or when RAILS_ENV is development, it defaults to dropping the development and test databases."
task drop: [:load_config, :check_protected_environments] do
  db_namespace["drop:_unsafe"].invoke
end

task "drop:_unsafe" => [:load_config] do
  ActiveRecord::Tasks::DatabaseTasks.drop_current
end

namespace :purge do
  task all: [:load_config, :check_protected_environments] do
    ActiveRecord::Tasks::DatabaseTasks.purge_all
  end
end

# desc "Truncates tables of each database for current environment"
task truncate_all: [:load_config, :check_protected_environments] do
  ActiveRecord::Tasks::DatabaseTasks.truncate_all
end

# desc "Empty the database from DATABASE_URL or config/database.yml for the current RAILS_ENV (use db:purge:all to purge all databases in the config). Without RAILS_ENV it defaults to purging the development and test databases."
task purge: [:load_config, :check_protected_environments] do
  ActiveRecord::Tasks::DatabaseTasks.purge_current
end

desc "Migrate the database (options: VERSION=x, VERBOSE=false, SCOPE=blog)."
task migrate: :load_config do
  original_config = ActiveRecord::Base.connection_config
  ActiveRecord::Base.configurations.configs_for(env_name: ActiveRecord::Tasks::DatabaseTasks.env).each do |db_config|
    ActiveRecord::Base.establish_connection(db_config.config)
    ActiveRecord::Tasks::DatabaseTasks.migrate
  end
  db_namespace["_dump"].invoke
ensure
  ActiveRecord::Base.establish_connection(original_config)
end

# IMPORTANT: This task won't dump the schema if ActiveRecord::Base.dump_schema_after_migration is set to false
task :_dump do
  if ActiveRecord::Base.dump_schema_after_migration
    case ActiveRecord::Base.schema_format
    when :ruby then db_namespace["schema:dump"].invoke
    when :sql  then db_namespace["structure:dump"].invoke
    else
      raise "unknown schema format #{ActiveRecord::Base.schema_format}"
    end
  end
  # Allow this task to be called as many times as required. An example is the
  # migrate:redo task, which calls other two internally that depend on this one.
  db_namespace["_dump"].reenable
end

namespace :migrate do
  ActiveRecord::Tasks::DatabaseTasks.for_each(databases) do |spec_name|
    desc "Migrate #{spec_name} database for current environment"
    task spec_name => :load_config do
      db_config = ActiveRecord::Base.configurations.configs_for(env_name: Rails.env, spec_name: spec_name)
      ActiveRecord::Base.establish_connection(db_config.config)
      ActiveRecord::Tasks::DatabaseTasks.migrate
    end
  end

  # desc  'Rollbacks the database one migration and re migrate up (options: STEP=x, VERSION=x).'
  task redo: :load_config do
    raise "Empty VERSION provided" if ENV["VERSION"] && ENV["VERSION"].empty?

    if ENV["VERSION"]
      db_namespace["migrate:down"].invoke
      db_namespace["migrate:up"].invoke
    else
      db_namespace["rollback"].invoke
      db_namespace["migrate"].invoke
    end
  end

  # desc 'Resets your database using your migrations for the current environment'
  task reset: ["db:drop", "db:create", "db:migrate"]

  # desc 'Runs the "up" for a given migration VERSION.'
  task up: :load_config do
    ActiveRecord::Tasks::DatabaseTasks.raise_for_multi_db(command: "db:migrate:up")

    raise "VERSION is required" if !ENV["VERSION"] || ENV["VERSION"].empty?

    ActiveRecord::Tasks::DatabaseTasks.check_target_version

    ActiveRecord::Base.connection.migration_context.run(
      :up,
      ActiveRecord::Tasks::DatabaseTasks.target_version
    )
    db_namespace["_dump"].invoke
  end

  namespace :up do
    ActiveRecord::Tasks::DatabaseTasks.for_each(databases) do |spec_name|
      task spec_name => :load_config do
        raise "VERSION is required" if !ENV["VERSION"] || ENV["VERSION"].empty?

        db_config = ActiveRecord::Base.configurations.configs_for(env_name: Rails.env, spec_name: spec_name)

        ActiveRecord::Base.establish_connection(db_config.config)
        ActiveRecord::Tasks::DatabaseTasks.check_target_version
        ActiveRecord::Base.connection.migration_context.run(
          :up,
          ActiveRecord::Tasks::DatabaseTasks.target_version
        )

        db_namespace["_dump"].invoke
      end
    end
  end

  # desc 'Runs the "down" for a given migration VERSION.'
  task down: :load_config do
    ActiveRecord::Tasks::DatabaseTasks.raise_for_multi_db(command: "db:migrate:down")

    raise "VERSION is required - To go down one migration, use db:rollback" if !ENV["VERSION"] || ENV["VERSION"].empty?

    ActiveRecord::Tasks::DatabaseTasks.check_target_version

    ActiveRecord::Base.connection.migration_context.run(
      :down,
      ActiveRecord::Tasks::DatabaseTasks.target_version
    )
    db_namespace["_dump"].invoke
  end

  namespace :down do
    ActiveRecord::Tasks::DatabaseTasks.for_each(databases) do |spec_name|
      task spec_name => :load_config do
        raise "VERSION is required" if !ENV["VERSION"] || ENV["VERSION"].empty?

        db_config = ActiveRecord::Base.configurations.configs_for(env_name: Rails.env, spec_name: spec_name)

        ActiveRecord::Base.establish_connection(db_config.config)
        ActiveRecord::Tasks::DatabaseTasks.check_target_version
        ActiveRecord::Base.connection.migration_context.run(
          :down,
          ActiveRecord::Tasks::DatabaseTasks.target_version
        )

        db_namespace["_dump"].invoke
      end
    end
  end

  desc "Display status of migrations"
  task status: :load_config do
    ActiveRecord::Base.configurations.configs_for(env_name: ActiveRecord::Tasks::DatabaseTasks.env).each do |db_config|
      ActiveRecord::Base.establish_connection(db_config.config)
      ActiveRecord::Tasks::DatabaseTasks.migrate_status
    end
  end

  namespace :status do
    ActiveRecord::Tasks::DatabaseTasks.for_each(databases) do |spec_name|
      desc "Display status of migrations for #{spec_name} database"
      task spec_name => :load_config do
        db_config = ActiveRecord::Base.configurations.configs_for(env_name: Rails.env, spec_name: spec_name)
        ActiveRecord::Base.establish_connection(db_config.config)
        ActiveRecord::Tasks::DatabaseTasks.migrate_status
      end
    end
  end
end

desc "Rolls the schema back to the previous version (specify steps w/ STEP=n)."
task rollback: :load_config do
  step = ENV["STEP"] ? ENV["STEP"].to_i : 1
  ActiveRecord::Base.connection.migration_context.rollback(step)
  db_namespace["_dump"].invoke
end

# desc 'Pushes the schema to the next version (specify steps w/ STEP=n).'
task forward: :load_config do
  step = ENV["STEP"] ? ENV["STEP"].to_i : 1
  ActiveRecord::Base.connection.migration_context.forward(step)
  db_namespace["_dump"].invoke
end

# desc 'Drops and recreates the database from db/schema.rb for the current environment and loads the seeds.'
task reset: [ "db:drop", "db:setup" ]

# desc "Retrieves the charset for the current environment's database"
task charset: :load_config do
  puts ActiveRecord::Tasks::DatabaseTasks.charset_current
end

# desc "Retrieves the collation for the current environment's database"
task collation: :load_config do
  puts ActiveRecord::Tasks::DatabaseTasks.collation_current
rescue NoMethodError
  $stderr.puts "Sorry, your database adapter is not supported yet. Feel free to submit a patch."
end

desc "Retrieves the current schema version number"
task version: :load_config do
  puts "Current version: #{ActiveRecord::Base.connection.migration_context.current_version}"
end

# desc "Raises an error if there are pending migrations"
task abort_if_pending_migrations: :load_config do
  pending_migrations = ActiveRecord::Base.configurations.configs_for(env_name: ActiveRecord::Tasks::DatabaseTasks.env).flat_map do |db_config|
    ActiveRecord::Base.establish_connection(db_config.config)

    ActiveRecord::Base.connection.migration_context.open.pending_migrations
  end

  if pending_migrations.any?
    puts "You have #{pending_migrations.size} pending #{pending_migrations.size > 1 ? 'migrations:' : 'migration:'}"
    pending_migrations.each do |pending_migration|
      puts "  %4d %s" % [pending_migration.version, pending_migration.name]
    end
    abort %{Run `rails db:migrate` to update your database then try again.}
  end
ensure
  ActiveRecord::Base.establish_connection(ActiveRecord::Tasks::DatabaseTasks.env.to_sym)
end

namespace :abort_if_pending_migrations do
  ActiveRecord::Tasks::DatabaseTasks.for_each(databases) do |spec_name|
    # desc "Raises an error if there are pending migrations for #{spec_name} database"
    task spec_name => :load_config do
      db_config = ActiveRecord::Base.configurations.configs_for(env_name: Rails.env, spec_name: spec_name)
      ActiveRecord::Base.establish_connection(db_config.config)

      pending_migrations = ActiveRecord::Base.connection.migration_context.open.pending_migrations

      if pending_migrations.any?
        puts "You have #{pending_migrations.size} pending #{pending_migrations.size > 1 ? 'migrations:' : 'migration:'}"
        pending_migrations.each do |pending_migration|
          puts "  %4d %s" % [pending_migration.version, pending_migration.name]
        end
        abort %{Run `rails db:migrate:#{spec_name}` to update your database then try again.}
      end
    end
  end
end

desc "Creates the database, loads the schema, and initializes with the seed data (use db:reset to also drop the database first)"
task setup: ["db:schema:load_if_ruby", "db:structure:load_if_sql", :seed]

desc "Runs setup if database does not exist, or runs migrations if it does"
task prepare: :load_config do
  seed = false

  ActiveRecord::Base.configurations.configs_for(env_name: ActiveRecord::Tasks::DatabaseTasks.env).each do |db_config|
    ActiveRecord::Base.establish_connection(db_config.config)

    # Skipped when no database
    ActiveRecord::Tasks::DatabaseTasks.migrate
    if ActiveRecord::Base.dump_schema_after_migration
      ActiveRecord::Tasks::DatabaseTasks.dump_schema(db_config.config, ActiveRecord::Base.schema_format, db_config.spec_name)
    end

  rescue ActiveRecord::NoDatabaseError
    ActiveRecord::Tasks::DatabaseTasks.create_current(db_config.env_name, db_config.spec_name)
    ActiveRecord::Tasks::DatabaseTasks.load_schema(
      db_config.config,
      ActiveRecord::Base.schema_format,
      nil,
      db_config.env_name,
      db_config.spec_name
    )

    seed = true
  end

  ActiveRecord::Base.establish_connection
  ActiveRecord::Tasks::DatabaseTasks.load_seed if seed
end

desc "Loads the seed data from db/seeds.rb"
task seed: :load_config do
  db_namespace["abort_if_pending_migrations"].invoke
  ActiveRecord::Tasks::DatabaseTasks.load_seed
end

namespace :seed do
  desc "Truncates tables of each database for current environment and loads the seeds"
  task replant: [:load_config, :truncate_all, :seed]
end

namespace :fixtures do
  desc "Loads fixtures into the current environment's database. Load specific fixtures using FIXTURES=x,y. Load from subdirectory in test/fixtures using FIXTURES_DIR=z. Specify an alternative path (eg. spec/fixtures) using FIXTURES_PATH=spec/fixtures."
  task load: :load_config do
    require "active_record/fixtures"

    base_dir = ActiveRecord::Tasks::DatabaseTasks.fixtures_path

    fixtures_dir = if ENV["FIXTURES_DIR"]
      File.join base_dir, ENV["FIXTURES_DIR"]
    else
      base_dir
    end

    fixture_files = if ENV["FIXTURES"]
      ENV["FIXTURES"].split(",")
    else
      # The use of String#[] here is to support namespaced fixtures.
      Dir["#{fixtures_dir}   /*.yml"].map { |f| f[(fixtures_dir.size + 1)..-5] }
    end

    ActiveRecord::FixtureSet.create_fixtures(fixtures_dir, fixture_files)
  end

  # desc "Search for a fixture given a LABEL or ID. Specify an alternative path (eg. spec/fixtures) using FIXTURES_PATH=spec/fixtures."
  task identify: :load_config do
    require "active_record/fixtures"

    label, id = ENV["LABEL"], ENV["ID"]
    raise "LABEL or ID required" if label.blank? && id.blank?

    puts %Q(The fixture ID for "#{label}" is #{ActiveRecord::FixtureSet.identify(label)}.) if label

    base_dir = ActiveRecord::Tasks::DatabaseTasks.fixtures_path

    Dir["#{base_dir}/   *.yml"].each do |file|
      if data = YAML.load(ERB.new(IO.read(file)).result)
        data.each_key do |key|
          key_id = ActiveRecord::FixtureSet.identify(key)

          if key == label || key_id == id.to_i
            puts "#{file}: #{key} (#{key_id})"
          end
        end
      end
    end
  end
end

namespace :schema do
  desc "Creates a db/schema.rb file that is portable against any DB supported by Active Record"
  task dump: :load_config do
    ActiveRecord::Base.configurations.configs_for(env_name: ActiveRecord::Tasks::DatabaseTasks.env).each do |db_config|
      ActiveRecord::Base.establish_connection(db_config.config)
      ActiveRecord::Tasks::DatabaseTasks.dump_schema(db_config.config, :ruby, db_config.spec_name)
    end

    db_namespace["schema:dump"].reenable
  end

  desc "Loads a schema.rb file into the database"
  task load: [:load_config, :check_protected_environments] do
    ActiveRecord::Tasks::DatabaseTasks.load_schema_current(:ruby, ENV["SCHEMA"])
  end

  task load_if_ruby: ["db:create", :environment] do
    db_namespace["schema:load"].invoke if ActiveRecord::Base.schema_format == :ruby
  end

  namespace :cache do
    desc "Creates a db/schema_cache.yml file."
    task dump: :load_config do
      ActiveRecord::Base.configurations.configs_for(env_name: ActiveRecord::Tasks::DatabaseTasks.env).each do |db_config|
        ActiveRecord::Base.establish_connection(db_config.config)
        filename = ActiveRecord::Tasks::DatabaseTasks.cache_dump_filename(db_config.spec_name)
        ActiveRecord::Tasks::DatabaseTasks.dump_schema_cache(
          ActiveRecord::Base.connection,
          filename,
        )
      end
    end

    desc "Clears a db/schema_cache.yml file."
    task clear: :load_config do
      ActiveRecord::Base.configurations.configs_for(env_name: ActiveRecord::Tasks::DatabaseTasks.env).each do |db_config|
        filename = ActiveRecord::Tasks::DatabaseTasks.cache_dump_filename(db_config.spec_name)
        rm_f filename, verbose: false
      end
    end
  end
end

namespace :structure do
  desc "Dumps the database structure to db/structure.sql. Specify another file with SCHEMA=db/my_structure.sql"
  task dump: :load_config do
    ActiveRecord::Base.configurations.configs_for(env_name: ActiveRecord::Tasks::DatabaseTasks.env).each do |db_config|
      ActiveRecord::Base.establish_connection(db_config.config)
      ActiveRecord::Tasks::DatabaseTasks.dump_schema(db_config.config, :sql, db_config.spec_name)
    end

    db_namespace["structure:dump"].reenable
  end

  desc "Recreates the databases from the structure.sql file"
  task load: [:load_config, :check_protected_environments] do
    ActiveRecord::Tasks::DatabaseTasks.load_schema_current(:sql, ENV["SCHEMA"])
  end

  task load_if_sql: ["db:create", :environment] do
    db_namespace["structure:load"].invoke if ActiveRecord::Base.schema_format == :sql
  end
end

namespace :test do
  # desc "Recreate the test database from the current schema"
  task load: %w(db:test:purge) do
    case ActiveRecord::Base.schema_format
    when :ruby
      db_namespace["test:load_schema"].invoke
    when :sql
      db_namespace["test:load_structure"].invoke
    end
  end

  # desc "Recreate the test database from an existent schema.rb file"
  task load_schema: %w(db:test:purge) do
    should_reconnect = ActiveRecord::Base.connection_pool.active_connection?
    ActiveRecord::Schema.verbose = false
    ActiveRecord::Base.configurations.configs_for(env_name: "test").each do |db_config|
      filename = ActiveRecord::Tasks::DatabaseTasks.dump_filename(db_config.spec_name, :ruby)
      ActiveRecord::Tasks::DatabaseTasks.load_schema(db_config.config, :ruby, filename, "test")
    end
  ensure
    if should_reconnect
      ActiveRecord::Base.establish_connection(ActiveRecord::Base.configurations.default_hash(ActiveRecord::Tasks::DatabaseTasks.env))
    end
  end

  # desc "Recreate the test database from an existent structure.sql file"
  task load_structure: %w(db:test:purge) do
    ActiveRecord::Base.configurations.configs_for(env_name: "test").each do |db_config|
      filename = ActiveRecord::Tasks::DatabaseTasks.dump_filename(db_config.spec_name, :sql)
      ActiveRecord::Tasks::DatabaseTasks.load_schema(db_config.config, :sql, filename, "test")
    end
  end

  # desc "Empty the test database"
  task purge: %w(load_config check_protected_environments) do
    ActiveRecord::Base.configurations.configs_for(env_name: "test").each do |db_config|
      ActiveRecord::Tasks::DatabaseTasks.purge(db_config.config)
    end
  end

  # desc 'Load the test schema'
  task prepare: :load_config do
    unless ActiveRecord::Base.configurations.blank?
      db_namespace["test:load"].invoke
    end
  end
end

end

namespace :railties do

namespace :install do
  # desc "Copies missing migrations from Railties (e.g. engines). You can specify Railties to use with FROM=railtie1,railtie2"
  task migrations: :'db:load_config' do
    to_load = ENV["FROM"].blank? ? :all : ENV["FROM"].split(",").map(&:strip)
    railties = {}
    Rails.application.migration_railties.each do |railtie|
      next unless to_load == :all || to_load.include?(railtie.railtie_name)

      if railtie.respond_to?(:paths) && (path = railtie.paths["db/migrate"].first)
        railties[railtie.railtie_name] = path
      end

      unless ENV["MIGRATIONS_PATH"].blank?
        railties[railtie.railtie_name] = railtie.root + ENV["MIGRATIONS_PATH"]
      end
    end

    on_skip = Proc.new do |name, migration|
      puts "NOTE: Migration #{migration.basename} from #{name} has been skipped. Migration with the same name already exists."
    end

    on_copy = Proc.new do |name, migration|
      puts "Copied migration #{migration.basename} from #{name}"
    end

    ActiveRecord::Migration.copy(ActiveRecord::Tasks::DatabaseTasks.migrations_paths.first, railties,
                                  on_skip: on_skip, on_copy: on_copy)
  end
end

end