dittolive-ditto 3.0.0-alpha2

Ditto is a peer to peer cross-platform database that allows mobile, web, IoT and server apps to sync with or without an internet connection.
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145

use core::ffi::c_void;
use std::sync::Arc;

use ffi_sdk::{BoxedAttachmentHandle, BoxedDitto};
use_prelude!();

use crate::{
    error::DittoError,
    store::{
        ditto_attachment::DittoAttachment, ditto_attachment_fetch_event::DittoAttachmentFetchEvent,
        ditto_attachment_token::DittoAttachmentToken,
    },
};

pub struct DittoAttachmentFetcher<'a> {
    context: Arc<DittoAttachmentFetcherCtx<'a>>,
    cancel_token: u64,
}

impl<'a> DittoAttachmentFetcher<'a> {
    pub fn new(
        token: DittoAttachmentToken,
        ditto: Arc<BoxedDitto>,
        on_fetch_event: impl Fn(DittoAttachmentFetchEvent) + Send + Sync + 'a,
    ) -> Result<Self, DittoError> {
        let context =
            DittoAttachmentFetcherCtx::new(token.clone(), ditto.retain(), Box::new(on_fetch_event));
        let arc_context = Arc::new(context);
        let raw_context = Arc::as_ptr(&arc_context) as *mut c_void;

        let cancel_token = unsafe {
            ffi_sdk::ditto_resolve_attachment(
                &ditto,
                token.id.as_ref().into(),
                raw_context,
                Some(DittoAttachmentFetcherCtx::retain),
                Some(DittoAttachmentFetcherCtx::release),
                DittoAttachmentFetcherCtx::on_complete_cb,
                DittoAttachmentFetcherCtx::on_progress_cb,
                DittoAttachmentFetcherCtx::on_deleted_cb,
            )
            .ok()?
        };

        Ok(Self {
            context: arc_context,
            cancel_token,
        })
    }
}

impl<'a> crate::observer::Observer for DittoAttachmentFetcher<'a> {}

impl<'a> Drop for DittoAttachmentFetcher<'a> {
    fn drop(&mut self) {
        let ret = unsafe {
            ffi_sdk::ditto_cancel_resolve_attachment(
                &self.context.ditto,
                self.context.token.id.as_ref().into(),
                self.cancel_token,
            )
        };

        if ret != 0 {
            log::warn!("Failed to clean up attachment fetcher.",);
        }
    }
}

struct DittoAttachmentFetcherCtx<'a> {
    token: DittoAttachmentToken,
    ditto: Arc<BoxedDitto>,
    on_fetch_event: Box<dyn Fn(DittoAttachmentFetchEvent) + Send + Sync + 'a>,
}

impl<'a> DittoAttachmentFetcherCtx<'a> {
    fn new(
        token: DittoAttachmentToken,
        ditto: Arc<BoxedDitto>,
        on_fetch_event: Box<dyn Fn(DittoAttachmentFetchEvent) + Send + Sync + 'a>,
    ) -> Self {
        Self {
            token,
            ditto,
            on_fetch_event,
        }
    }

    pub(crate) unsafe extern "C" fn retain(ctx: *mut c_void) {
        let ptr = ctx.cast::<DittoAttachmentFetcherCtx>();
        Arc::increment_strong_count(ptr);
    }

    pub(crate) unsafe extern "C" fn release(ctx: *mut c_void) {
        let ptr = ctx.cast::<DittoAttachmentFetcherCtx>();
        Arc::decrement_strong_count(ptr);
    }

    pub(crate) unsafe extern "C" fn on_complete_cb(
        ctx: *mut c_void,
        attachment_handle: BoxedAttachmentHandle,
    ) {
        let ctx_ref = ctx
            .cast::<DittoAttachmentFetcherCtx>()
            .as_ref()
            .expect("got null");

        let ditto_attachment = DittoAttachment::new_with_token(
            ctx_ref.token.clone(),
            ctx_ref.ditto.retain(),
            attachment_handle,
        );
        let event = DittoAttachmentFetchEvent::Completed {
            attachment: ditto_attachment,
        };
        (ctx_ref.on_fetch_event)(event);
    }

    pub(crate) unsafe extern "C" fn on_progress_cb(
        ctx: *mut c_void,
        downloaded_bytes: u64,
        total_bytes: u64,
    ) {
        let ctx_ref = ctx
            .cast::<DittoAttachmentFetcherCtx>()
            .as_ref()
            .expect("got null");

        let event = DittoAttachmentFetchEvent::Progress {
            downloaded_bytes,
            total_bytes,
        };
        (ctx_ref.on_fetch_event)(event);
    }

    pub(crate) unsafe extern "C" fn on_deleted_cb(ctx: *mut c_void) {
        let ctx_ref = ctx
            .cast::<DittoAttachmentFetcherCtx>()
            .as_ref()
            .expect("got null");

        let event = DittoAttachmentFetchEvent::Deleted;
        (ctx_ref.on_fetch_event)(event);
    }
}