property.go

/*
	Copyright 2020 The pdfcpu 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

		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 api

import (
	"io"
	"os"
	"time"

	"github.com/pdfcpu/pdfcpu/pkg/pdfcpu"
	"github.com/pdfcpu/pdfcpu/pkg/pdfcpu/model"
	"github.com/pkg/errors"
)

// Properties returns rs's properties as recorded in infoDict.
func Properties(rs io.ReadSeeker, conf *model.Configuration) (map[string]string, error) {
	if rs == nil {
		return nil, errors.New("pdfcpu: ListProperties: missing rs")
	}

	if conf == nil {
		conf = model.NewDefaultConfiguration()
	} else {
		// Validation loads infodict.
		conf.ValidationMode = model.ValidationRelaxed
	}
	conf.Cmd = model.LISTPROPERTIES

	ctx, _, _, _, err := ReadValidateAndOptimize(rs, conf, time.Now())
	if err != nil {
		return nil, err
	}

	return ctx.Properties, nil
}

// AddProperties adds properties to rs's infodict and writes the result to w.
func AddProperties(rs io.ReadSeeker, w io.Writer, properties map[string]string, conf *model.Configuration) error {
	if rs == nil {
		return errors.New("pdfcpu: AddProperties: missing rs")
	}

	if conf == nil {
		conf = model.NewDefaultConfiguration()
	} else {
		// Validation loads infodict.
		conf.ValidationMode = model.ValidationRelaxed
	}
	conf.Cmd = model.ADDPROPERTIES

	fromStart := time.Now()
	ctx, durRead, durVal, durOpt, err := ReadValidateAndOptimize(rs, conf, fromStart)
	if err != nil {
		return err
	}

	from := time.Now()

	if err = pdfcpu.PropertiesAdd(ctx, properties); err != nil {
		return err
	}

	durAdd := time.Since(from).Seconds()
	fromWrite := time.Now()

	if err = WriteContext(ctx, w); err != nil {
		return err
	}

	durWrite := durAdd + time.Since(fromWrite).Seconds()
	durTotal := time.Since(fromStart).Seconds()
	logOperationStats(ctx, "add keyword, write", durRead, durVal, durOpt, durWrite, durTotal)

	return nil
}

// AddPropertiesFile adds properties to inFile's infodict and writes the result to outFile.
func AddPropertiesFile(inFile, outFile string, properties map[string]string, conf *model.Configuration) (err error) {
	var f1, f2 *os.File

	if f1, err = os.Open(inFile); err != nil {
		return err
	}

	tmpFile := inFile + ".tmp"
	if outFile != "" && inFile != outFile {
		tmpFile = outFile
	}
	if f2, err = os.Create(tmpFile); err != nil {
		f1.Close()
		return err
	}

	defer func() {
		if err != nil {
			f2.Close()
			f1.Close()
			os.Remove(tmpFile)
			return
		}
		if err = f2.Close(); err != nil {
			return
		}
		if err = f1.Close(); err != nil {
			return
		}
		if outFile == "" || inFile == outFile {
			err = os.Rename(tmpFile, inFile)
		}
	}()

	return AddProperties(f1, f2, properties, conf)
}

// RemoveProperties deletes properties from rs's infodict and writes the result to w.
func RemoveProperties(rs io.ReadSeeker, w io.Writer, properties []string, conf *model.Configuration) error {
	if rs == nil {
		return errors.New("pdfcpu: RemoveProperties: missing rs")
	}

	if conf == nil {
		conf = model.NewDefaultConfiguration()
	} else {
		// Validation loads infodict.
		conf.ValidationMode = model.ValidationRelaxed
	}
	conf.Cmd = model.REMOVEPROPERTIES

	fromStart := time.Now()
	ctx, durRead, durVal, durOpt, err := ReadValidateAndOptimize(rs, conf, fromStart)
	if err != nil {
		return err
	}

	from := time.Now()

	var ok bool
	if ok, err = pdfcpu.PropertiesRemove(ctx, properties); err != nil {
		return err
	}
	if !ok {
		return errors.New("no property removed")
	}

	durRemove := time.Since(from).Seconds()
	fromWrite := time.Now()
	if err = WriteContext(ctx, w); err != nil {
		return err
	}

	durWrite := durRemove + time.Since(fromWrite).Seconds()
	durTotal := time.Since(fromStart).Seconds()
	logOperationStats(ctx, "remove prop, write", durRead, durVal, durOpt, durWrite, durTotal)

	return nil
}

// RemovePropertiesFile deletes properties from inFile's infodict and writes the result to outFile.
func RemovePropertiesFile(inFile, outFile string, properties []string, conf *model.Configuration) (err error) {
	var f1, f2 *os.File

	if f1, err = os.Open(inFile); err != nil {
		return err
	}

	tmpFile := inFile + ".tmp"
	if outFile != "" && inFile != outFile {
		tmpFile = outFile
	}
	if f2, err = os.Create(tmpFile); err != nil {
		f1.Close()
		return err
	}

	defer func() {
		if err != nil {
			f2.Close()
			f1.Close()
			os.Remove(tmpFile)
			return
		}
		if err = f2.Close(); err != nil {
			return
		}
		if err = f1.Close(); err != nil {
			return
		}
		if outFile == "" || inFile == outFile {
			err = os.Rename(tmpFile, inFile)
		}
	}()

	return RemoveProperties(f1, f2, properties, conf)
}