1/*
2 * Copyright (C) 2016 The Android Open Source Project
3 * Copyright (C) 2016 Mopria Alliance, Inc.
4 * Copyright (C) 2013 Hewlett-Packard Development Company, L.P.
5 *
6 * Licensed under the Apache License, Version 2.0 (the "License");
7 * you may not use this file except in compliance with the License.
8 * You may obtain a copy of the License at
9 *
10 *      http://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing, software
13 * distributed under the License is distributed on an "AS IS" BASIS,
14 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15 * See the License for the specific language governing permissions and
16 * limitations under the License.
17 */
18#include <jni.h>
19#include <malloc.h>
20#include "wprint_mupdf.h"
21#include "wprint_debug.h"
22
23#define TAG "pdf_render"
24
25/* Global reference to JVM */
26extern JavaVM *_JVM;
27
28/* Local data associated with pdf_render_st instances */
29typedef struct pdf_render_st {
30    /* Public interface. Must be first. */
31    pdf_render_ifc_t ifc;
32
33    /* JNI environment */
34    JNIEnv *env;
35
36    /* true if the env was created for this thread */
37    bool needDetach;
38
39    /* Reference to associated PdfRender object */
40    jobject obj;
41} pdf_render_st_t;
42
43static jclass gPdfRenderClass;
44static jmethodID gPdfRenderOpenDocument, gPdfRenderGetPageSize, gPdfRenderRenderPageStripe;
45static jclass gSizeDClass;
46static jmethodID gSizeDGetHeight, gSizeDGetWidth;
47
48static int openDocument(pdf_render_ifc_t *obj, const char *fileName) {
49    LOGD("getPageCount %p %s", obj, fileName);
50    if (!gPdfRenderClass) return ERROR;
51
52    pdf_render_st_t *self = (pdf_render_st_t *) obj;
53    jstring fileNameString = (*self->env)->NewStringUTF(self->env, fileName);
54    int count = (*self->env)->CallIntMethod(self->env, self->obj, gPdfRenderOpenDocument,
55            fileNameString);
56    LOGD("getPageCount %p %s returning %d", obj, fileName, count);
57    return count;
58}
59
60static int getPageAttributes(pdf_render_ifc_t *obj, int page, double *width, double *height) {
61    LOGD("getPageAttributes %p %d", obj, page);
62    if (!gPdfRenderClass) return ERROR;
63
64    pdf_render_st_t *self = (pdf_render_st_t *) obj;
65
66    jobject size = (*self->env)->CallObjectMethod(self->env, self->obj, gPdfRenderGetPageSize,
67            page);
68    if (size == NULL) return ERROR;
69
70    // Extract width/height and return them
71    *width = (double) (*self->env)->CallDoubleMethod(self->env, size, gSizeDGetWidth);
72    *height = (double) (*self->env)->CallDoubleMethod(self->env, size, gSizeDGetHeight);
73    return OK;
74}
75
76static int renderPageStripe(pdf_render_ifc_t *obj, int page, int width, int height, float zoom,
77        char *buffer) {
78    LOGD("renderPageStripe %p %d", obj, page);
79    if (!gPdfRenderClass) return ERROR;
80
81    pdf_render_st_t *self = (pdf_render_st_t *) obj;
82
83    int bufferSize = width * height * 3;
84    jobject byteBuffer = (*self->env)->NewDirectByteBuffer(self->env, buffer, bufferSize);
85
86    if (!(*self->env)->CallBooleanMethod(self->env, self->obj, gPdfRenderRenderPageStripe, page,
87            0, width, height, (double) zoom, byteBuffer)) {
88        return ERROR;
89    }
90
91    (*self->env)->DeleteLocalRef(self->env, byteBuffer);
92    return OK;
93}
94
95static void destroy(pdf_render_ifc_t *obj) {
96    LOGD("destroy %p", obj);
97    pdf_render_st_t *self = (pdf_render_st_t *) obj;
98
99    (*self->env)->DeleteGlobalRef(self->env, self->obj);
100
101    if (self->needDetach) {
102        (*_JVM)->DetachCurrentThread(_JVM);
103    }
104
105    free(self);
106}
107
108void pdf_render_init(JNIEnv *env) {
109    LOGD("pdf_render_init");
110
111    /* Lock down global class references and look up method IDs */
112    gPdfRenderClass = (*env)->NewGlobalRef(env, (*env)->FindClass(env,
113            "com/android/bips/jni/PdfRender"));
114    gPdfRenderOpenDocument = (*env)->GetMethodID(env, gPdfRenderClass, "openDocument",
115            "(Ljava/lang/String;)I");
116    gPdfRenderGetPageSize = (*env)->GetMethodID(env, gPdfRenderClass, "getPageSize",
117            "(I)Lcom/android/bips/jni/SizeD;");
118    gPdfRenderRenderPageStripe = (*env)->GetMethodID(env, gPdfRenderClass, "renderPageStripe",
119            "(IIIIDLjava/nio/ByteBuffer;)Z");
120
121    gSizeDClass = (*env)->NewGlobalRef(env, (*env)->FindClass(env, "com/android/bips/jni/SizeD"));
122    gSizeDGetWidth = (*env)->GetMethodID(env, gSizeDClass, "getWidth", "()D");
123    gSizeDGetHeight = (*env)->GetMethodID(env, gSizeDClass, "getHeight", "()D");
124}
125
126void pdf_render_deinit(JNIEnv *env) {
127    LOGD("pdf_render_deinit");
128    (*env)->DeleteGlobalRef(env, gPdfRenderClass);
129    (*env)->DeleteGlobalRef(env, gSizeDClass);
130    gPdfRenderClass = 0;
131}
132
133pdf_render_ifc_t *create_pdf_render_ifc() {
134    LOGD("create_pdf_render_ifc");
135
136    pdf_render_st_t *self;
137
138    // Set up the interface
139    self = (pdf_render_st_t *) malloc(sizeof(pdf_render_st_t));
140    if (!self) return NULL;
141
142    self->ifc.openDocument = openDocument;
143    self->ifc.getPageAttributes = getPageAttributes;
144    self->ifc.renderPageStripe = renderPageStripe;
145    self->ifc.destroy = destroy;
146
147    // Get the environment
148    jint result = (*_JVM)->GetEnv(_JVM, (void **) &self->env, JNI_VERSION_1_6);
149    if (result == JNI_EDETACHED) {
150        self->needDetach = true;
151        if ((*_JVM)->AttachCurrentThread(_JVM, &self->env, NULL) < 0) {
152            LOGE("AttachCurrentThread failed");
153            free(self);
154            return NULL;
155        }
156    } else {
157        self->needDetach = false;
158    }
159
160    // Get the object
161    jmethodID methodId = (*self->env)->GetStaticMethodID(self->env, gPdfRenderClass, "getInstance",
162            "(Landroid/content/Context;)Lcom/android/bips/jni/PdfRender;");
163    jobject instance = (*self->env)->CallStaticObjectMethod(self->env, gPdfRenderClass, methodId,
164            NULL);
165    self->obj = (*self->env)->NewGlobalRef(self->env, instance);
166
167    return &self->ifc;
168}