From e3b8082f631df356da3b7c58c8c9e17966bafc3e Mon Sep 17 00:00:00 2001
From: luhuaei <luhuaei@gmail.com>
Date: Sun, 15 Dec 2019 11:25:43 +0800
Subject: [PATCH] add pdf-viewer jump link base on keyboard.

---
 app/pdf-viewer/buffer.py | 71 ++++++++++++++++++++++++++++++++++++++--
 eaf.el                   |  3 +-
 2 files changed, 70 insertions(+), 4 deletions(-)

diff --git a/app/pdf-viewer/buffer.py b/app/pdf-viewer/buffer.py
index a8d69e4..948669a 100755
--- a/app/pdf-viewer/buffer.py
+++ b/app/pdf-viewer/buffer.py
@@ -27,6 +27,7 @@ from PyQt5.QtWidgets import QWidget
 from core.buffer import Buffer
 import fitz
 import time
+import random
 
 class AppBuffer(Buffer):
     def __init__(self, buffer_id, url, arguments):
@@ -41,6 +42,8 @@ class AppBuffer(Buffer):
             self.buffer_widget.jump_to_page(int(result_content))
         elif result_type == "jump_percent":
             self.buffer_widget.jump_to_percent(int(result_content))
+        elif result_type == "jump_link":
+            self.buffer_widget.jump_to_link(str(result_content))
 
     def scroll(self, scroll_direction, scroll_type):
         if scroll_type == "page":
@@ -113,6 +116,10 @@ class AppBuffer(Buffer):
     def toggle_inverted_mode(self):
         self.buffer_widget.toggle_inverted_mode()
 
+    def jump_to_link(self):
+        self.buffer_widget.add_mark_jump_link_tips()
+        self.buffer_widget.send_input_message("Jump to link: ", "jump_link")
+
 class PdfViewerWidget(QWidget):
     translate_double_click_word = QtCore.pyqtSignal(str)
 
@@ -139,6 +146,10 @@ class PdfViewerWidget(QWidget):
         # Inverted mode.
         self.inverted_mode = False
 
+        #jump link
+        self.jump_link_key_cache_dict = {}
+        self.jump_link_annot_cache_dict = {}
+
         # Init scroll attributes.
         self.scroll_step = 20
         self.scroll_offset = 0
@@ -406,6 +417,63 @@ class PdfViewerWidget(QWidget):
         # Re-render page.
         self.update()
 
+    def generate_random_key(self, count):
+        letters = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+        key_list = []
+        while count > 0:
+            key = ''.join(random.choices(letters, k=2))
+            if key not in key_list:
+                key_list.append(key)
+                count -= 1
+        return key_list
+
+    def add_mark_jump_link_tips(self):
+        # Only mark display page
+        start_page_index = self.get_start_page_index()
+        last_page_index = self.get_last_page_index()
+        tips_size = 7
+        annot_list = []
+
+        for page_index in range(start_page_index, last_page_index):
+            page = self.document[page_index]
+            annot_list = []
+            if page.firstLink:
+                links = page.getLinks()
+                key_list = self.generate_random_key(len(links))
+                for index, link in enumerate(links):
+                    key = key_list[index]
+                    link_rect = link["from"]
+                    annot_rect = fitz.Rect(link_rect.top_left, link_rect.x0 + tips_size, link_rect.y0 + tips_size)
+                    annot = page.addFreetextAnnot(annot_rect, str(key), fontsize=6, fontname="Cour", \
+                                                  text_color=[0.0, 0.0, 0.0], fill_color=[255/255.0, 197/255.0, 36/255.0])
+                    annot.parent = page
+                    annot_list.append(annot)
+                    self.jump_link_key_cache_dict[key] = link
+
+            self.jump_link_annot_cache_dict[page_index] = annot_list
+
+        self.page_cache_pixmap_dict.clear()
+        self.update()
+
+    def delete_all_mark_jump_link_tips(self):
+        if self.jump_link_annot_cache_dict:
+            for index in self.jump_link_annot_cache_dict.keys():
+                page = self.document[index]
+                for annot in self.jump_link_annot_cache_dict[index]:
+                    page.deleteAnnot(annot)
+        self.jump_link_key_cache_dict.clear()
+        self.jump_link_annot_cache_dict.clear()
+        self.update()
+
+    def jump_to_link(self, key):
+        key = str(key).upper()
+        if key in self.jump_link_key_cache_dict:
+            link = self.jump_link_key_cache_dict[key]
+            self.remember_current_position()
+            self.jump_to_page(link["page"] + 1)
+        self.delete_all_mark_jump_link_tips()
+        self.update()
+
     def jump_to_page(self, page_num):
         self.update_scroll_offset(min(max(self.scale * (int(page_num) - 1) * self.page_height, 0), self.max_scroll_offset()))
 
@@ -469,9 +537,6 @@ class PdfViewerWidget(QWidget):
         if rect_words:
             return rect_words[0][4]
 
-    def enterEvent(self, event):
-        pass
-
     def eventFilter(self, obj, event):
         if event.type() == QEvent.MouseButtonPress:
             event_link = self.get_event_link(event)
diff --git a/eaf.el b/eaf.el
index 2b45949..f49b0fc 100644
--- a/eaf.el
+++ b/eaf.el
@@ -235,7 +235,8 @@ Try not to modify this alist directly. Use `eaf-setq' to modify instead."
     ("p" . "jump_to_percent")
     ("[" . "remember_current_position")
     ("]" . "remember_jump")
-    ("i" . "toggle_inverted_mode"))
+    ("i" . "toggle_inverted_mode")
+    ("f" . "jump_to_link"))
   "The keybinding of EAF PDF Viewer."
   :type 'cons)