1 files changed, 236 insertions, 0 deletions
diff --git a/document/document.go b/document/document.go
new file mode 100644
index 0000000..a036eee
--- /dev/null
+++ b/document/document.go
@@ -0,0 +1,236 @@
+package document
+
+import (
+	"github.com/scrotadamus/ghligh/go-poppler"
+
+	"os"
+	"sync"
+
+	"strings"
+
+	"fmt"
+)
+
+const ghlighFilter = "ghligh-Y2lhbm5v:"
+
+// This is different from poppler's annot_mapping
+// it is the list of annotations mapped to the page index
+type AnnotsMap map[int][]AnnotJSON
+
+type GhlighDoc struct {
+	doc *poppler.Document
+	mu  sync.Mutex
+
+	Path         string    `json:"file"`
+	HashBuffer   string    `json:"hash"`
+	AnnotsBuffer AnnotsMap `json:"highlights,omitempty"`
+}
+
+type HighlightedText struct {
+	Page     int    `json:"page"`
+	Text     string `json:"text"`
+	Contents string `json:"contents,omitempty"`
+}
+
+func Open(filename string) (*GhlighDoc, error) {
+	var err error
+
+	g := &GhlighDoc{}
+
+	g.doc, err = poppler.Open(filename)
+	if err != nil {
+		fmt.Errorf("%s: error opening pdf %v", os.Args[0], err)
+		return nil, err
+	}
+	g.Path = filename
+	// HashDoc??
+
+	return g, nil
+}
+
+func (d *GhlighDoc) Close() {
+	d.AnnotsBuffer = nil
+	d.HashBuffer = ""
+	if d.doc != nil {
+		d.doc.Close()
+	}
+}
+
+func (d *GhlighDoc) Info() poppler.DocumentInfo {
+	return d.doc.Info()
+}
+
+func (d *GhlighDoc) tagExists(text string) bool {
+	for _, tag := range d.GetTags() {
+		if tag == text {
+			return true
+		}
+	}
+	return false
+}
+
+func (d *GhlighDoc) Tag(text string) {
+	if !d.tagExists(text) {
+		d.doc.Tag(ghlighFilter + text)
+	} else {
+		fmt.Fprintf(os.Stderr, "warning: tag %s already exist inside %s, i don't do anything\n", text, d.Path)
+	}
+}
+
+func (d *GhlighDoc) GetTags() []string {
+	var tags []string
+	annots := d.doc.GetTags(ghlighFilter)
+	for _, annot := range annots {
+		contents := strings.TrimPrefix(annot.Contents(), ghlighFilter)
+		tags = append(tags, contents)
+	}
+	return tags
+}
+
+func (d *GhlighDoc) RemoveTags(tags []string) int {
+	zeroPage := d.doc.GetPage(0)
+	var removedTags int
+
+	annots := d.doc.GetTags(ghlighFilter)
+	for _, annot := range annots {
+		contents := strings.TrimPrefix(annot.Contents(), ghlighFilter)
+		for _, tag := range tags {
+			if tag == contents {
+				zeroPage.RemoveAnnot(*annot)
+				removedTags += 1
+				break
+			}
+		}
+	}
+	return removedTags
+}
+
+func (d *GhlighDoc) Import(annotsMap AnnotsMap) (int, error) {
+	d.mu.Lock()
+	defer d.mu.Unlock()
+	annots_count := 0
+
+	var err error
+	d.AnnotsBuffer = annotsMap
+
+	for key := range d.AnnotsBuffer {
+		page := d.doc.GetPage(key)
+		for _, annot := range d.AnnotsBuffer[key] {
+			a := d.jsonToAnnot(annot)
+			if !isInPage(a, page) {
+				annots_count += 1
+				page.AddAnnot(*a)
+			}
+
+		}
+		page.Close()
+	}
+
+	d.AnnotsBuffer = nil
+	return annots_count, err
+}
+
+func integrityCheck(tizio *GhlighDoc, caio *GhlighDoc) {
+
+}
+
+func (d *GhlighDoc) Save() (bool, error) {
+	d.mu.Lock()
+	defer d.mu.Unlock()
+	tempFile, err := os.CreateTemp("", ".ghligh_*.pdf")
+	if err != nil {
+		return false, err
+	}
+	defer os.Remove(tempFile.Name())
+
+	ok, err := d.doc.Save(tempFile.Name())
+	if !ok {
+		return false, err
+	}
+
+	/* integrity check */
+	newDoc, err := Open(tempFile.Name())
+	if err != nil {
+		return false, err
+	}
+
+	if newDoc.HashDoc() != d.HashDoc() {
+		return false, fmt.Errorf("After saving document %s to %s its hash doesn't correspond the the old one", d.Path, tempFile.Name())
+	}
+
+	err = os.Rename(tempFile.Name(), d.Path)
+	if err != nil {
+		return false, err
+	}
+
+	return true, nil
+}
+
+func (d *GhlighDoc) Cat() []HighlightedText {
+	var highlights []HighlightedText
+
+	n_pages := d.doc.GetNPages()
+	for i := 0; i < n_pages; i++ {
+		page := d.doc.GetPage(i)
+		annots := page.GetAnnots()
+		for _, annot := range annots {
+			if annot.Type() == poppler.AnnotHighlight {
+				annotText := page.AnnotText(*annot)
+
+				highlights = append(highlights, HighlightedText{Page: i, Text: annotText, Contents: annot.Contents()})
+			}
+		}
+
+		page.Close()
+	}
+	return highlights
+}
+
+func (d *GhlighDoc) HasHighlights() bool {
+	// check if is tagged with ls
+	if d.tagExists("ls") {
+		return true
+	}
+
+	// check if it has highlights
+	n_pages := d.doc.GetNPages()
+	for i := 0; i < n_pages; i++ {
+		page := d.doc.GetPage(i)
+		annots := page.GetAnnots()
+		for _, annot := range annots {
+			if annot.Type() == poppler.AnnotHighlight {
+				return true
+			}
+		}
+
+		page.Close()
+	}
+	return false
+}
+
+func (d *GhlighDoc) GetAnnotsBuffer() AnnotsMap {
+	annots_json_of_page := make(AnnotsMap)
+
+	n := d.doc.GetNPages()
+	var annots_json []AnnotJSON
+	for i := 0; i < n; i++ {
+		annots_json = nil
+		page := d.doc.GetPage(i)
+
+		annots := page.GetAnnots()
+		for _, annot := range annots {
+			if annot.Type() == poppler.AnnotHighlight {
+				annot_json := annotToJson(*annot)
+				annots_json = append(annots_json, annot_json)
+			}
+		}
+
+		page.Close()
+
+		if len(annots_json) > 0 {
+			annots_json_of_page[i] = annots_json
+		}
+	}
+
+	return annots_json_of_page
+}