Allow customization of charger animation

Allow the charging animation to be customized with a configuration file
and custom assets.

 - Add a parser to parse a custom configuration file.
 - Add support for showing a clock and the battery percentage.
 - Expand feature that conditionally shows animation frames using min_level
   and level_only to min_level and max_level

BUG: 29547343
Change-Id: Ia33f4bb37dc7d4c7fa6507a63481e93bf0bf9738
diff --git a/healthd/AnimationParser.cpp b/healthd/AnimationParser.cpp
new file mode 100644
index 0000000..864038b
--- /dev/null
+++ b/healthd/AnimationParser.cpp
@@ -0,0 +1,141 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * 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.
+ */
+
+#include "AnimationParser.h"
+
+#include <android-base/stringprintf.h>
+#include <android-base/strings.h>
+
+#include <cutils/klog.h>
+
+#include "animation.h"
+
+#define LOGE(x...) do { KLOG_ERROR("charger", x); } while (0)
+#define LOGW(x...) do { KLOG_WARNING("charger", x); } while (0)
+#define LOGV(x...) do { KLOG_DEBUG("charger", x); } while (0)
+
+namespace android {
+
+// Lines consisting of only whitespace or whitespace followed by '#' can be ignored.
+bool can_ignore_line(const char* str) {
+    for (int i = 0; str[i] != '\0' && str[i] != '#'; i++) {
+        if (!isspace(str[i])) return false;
+    }
+    return true;
+}
+
+bool remove_prefix(const std::string& line, const char* prefix, const char** rest) {
+    const char* str = line.c_str();
+    int start;
+    char c;
+
+    std::string format = base::StringPrintf(" %s%%n%%c", prefix);
+    if (sscanf(str, format.c_str(), &start, &c) != 1) {
+        return false;
+    }
+
+    *rest = &str[start];
+    return true;
+}
+
+bool parse_text_field(const char* in, animation::text_field* field) {
+    int* x = &field->pos_x;
+    int* y = &field->pos_y;
+    int* r = &field->color_r;
+    int* g = &field->color_g;
+    int* b = &field->color_b;
+    int* a = &field->color_a;
+
+    int start = 0, end = 0;
+
+    if (sscanf(in, "c c %d %d %d %d %n%*s%n", r, g, b, a, &start, &end) == 4) {
+        *x = CENTER_VAL;
+        *y = CENTER_VAL;
+    } else if (sscanf(in, "c %d %d %d %d %d %n%*s%n", y, r, g, b, a, &start, &end) == 5) {
+        *x = CENTER_VAL;
+    } else if (sscanf(in, "%d c %d %d %d %d %n%*s%n", x, r, g, b, a, &start, &end) == 5) {
+        *y = CENTER_VAL;
+    } else if (sscanf(in, "%d %d %d %d %d %d %n%*s%n", x, y, r, g, b, a, &start, &end) != 6) {
+        return false;
+    }
+
+    if (end == 0) return false;
+
+    field->font_file.assign(&in[start], end - start);
+
+    return true;
+}
+
+bool parse_animation_desc(const std::string& content, animation* anim) {
+    static constexpr const char* animation_prefix = "animation: ";
+    static constexpr const char* fail_prefix = "fail: ";
+    static constexpr const char* clock_prefix = "clock_display: ";
+    static constexpr const char* percent_prefix = "percent_display: ";
+    static constexpr const char* frame_prefix = "frame: ";
+
+    std::vector<animation::frame> frames;
+
+    for (const auto& line : base::Split(content, "\n")) {
+        animation::frame frame;
+        const char* rest;
+
+        if (can_ignore_line(line.c_str())) {
+            continue;
+        } else if (remove_prefix(line, animation_prefix, &rest)) {
+            int start = 0, end = 0;
+            if (sscanf(rest, "%d %d %n%*s%n", &anim->num_cycles, &anim->first_frame_repeats,
+                    &start, &end) != 2 ||
+                end == 0) {
+                LOGE("Bad animation format: %s\n", line.c_str());
+                return false;
+            } else {
+                anim->animation_file.assign(&rest[start], end - start);
+            }
+        } else if (remove_prefix(line, fail_prefix, &rest)) {
+            anim->fail_file.assign(rest);
+        } else if (remove_prefix(line, clock_prefix, &rest)) {
+            if (!parse_text_field(rest, &anim->text_clock)) {
+                LOGE("Bad clock_display format: %s\n", line.c_str());
+                return false;
+            }
+        } else if (remove_prefix(line, percent_prefix, &rest)) {
+            if (!parse_text_field(rest, &anim->text_percent)) {
+                LOGE("Bad percent_display format: %s\n", line.c_str());
+                return false;
+            }
+        } else if (sscanf(line.c_str(), " frame: %d %d %d",
+                &frame.disp_time, &frame.min_level, &frame.max_level) == 3) {
+            frames.push_back(std::move(frame));
+        } else {
+            LOGE("Malformed animation description line: %s\n", line.c_str());
+            return false;
+        }
+    }
+
+    if (anim->animation_file.empty() || frames.empty()) {
+        LOGE("Bad animation description. Provide the 'animation: ' line and at least one 'frame: ' "
+             "line.\n");
+        return false;
+    }
+
+    anim->num_frames = frames.size();
+    anim->frames = new animation::frame[frames.size()];
+    std::copy(frames.begin(), frames.end(), anim->frames);
+
+    return true;
+}
+
+}  // namespace android