# syntax=docker/dockerfile:1
#
# djvu-rs 0.42.0 (Mikhail Matyushkin; MIT, written from the DjVu v3
# specification, no GPL code) compiled to WebAssembly for johnmcm.com's
# /djvu-to-pdf and /open-file/djvu: this folder's small crate (src/lib.rs)
# re-exports djvu-rs's own viewer bindings and adds PDF export and
# bookmarks, built with wasm-pack for ES-module workers with WebAssembly
# SIMD on. The Rust image is pinned by digest, djvu-rs by exact version, the
# crates by Cargo.lock (generated by the first build and kept here).
#
#   ./build.ps1     (or)   docker build --target export --output type=local,dest=dist .

ARG RUST_IMAGE=rust:1.89-bookworm@sha256:948f9b08a66e7fe01b03a98ef1c7568292e07ec2e4fe90d88c07bb14563c84ff
FROM ${RUST_IMAGE} AS build

RUN rustup target add wasm32-unknown-unknown \
 && cargo install --locked wasm-pack --version 0.13.1

# djvu-rs itself, from crates.io (checked against the checksum Cargo.lock
# records), with two patches: the PDF's invisible text layer in Unicode, and
# links between pages that work (patches/pdf-text-and-links.patch, using
# font/glyphless.ttf); then links and bookmarks that name a page by number,
# by component name or by a step from the current page, resolved against the
# whole book and shifted for a page range (patches/link-scope.patch, whose
# unit tests run here). Cargo.toml's [patch.crates-io] points the build at
# this copy.
ARG DJVU_RS_VERSION=0.42.0
ARG DJVU_RS_SHA256=c39f7585887a2d8a22e49593e47c2bf679cf302403935f8868afc5acad39b759
WORKDIR /src
COPY patches/ /patches/
COPY font/glyphless.ttf /patches/
RUN curl -fsSL -o djvu-rs.crate https://crates.io/api/v1/crates/djvu-rs/${DJVU_RS_VERSION}/download \
 && echo "${DJVU_RS_SHA256}  djvu-rs.crate" | sha256sum -c - \
 && tar xzf djvu-rs.crate && mv djvu-rs-${DJVU_RS_VERSION} djvu-rs \
 && cd djvu-rs && sed 's/\r$//' /patches/pdf-text-and-links.patch | patch -p1 \
 && sed 's/\r$//' /patches/link-scope.patch | patch -p1 \
 && cp /patches/glyphless.ttf src/pdf/glyphless.ttf
# The link resolver's own tests, on a scratch copy: djvu-rs's PDF test module
# no longer compiles against the text-layer patch (it calls the Helvetica
# font helper that patch replaced), so it is left out there only.
RUN cp -r djvu-rs /tmp/test && cd /tmp/test \
 && sed -i 's/^mod tests;$/mod tests {}/' src/pdf/mod.rs \
 && cargo test --lib --no-default-features --features std,pdf link_scope_tests \
 && rm -rf /tmp/test

WORKDIR /djvu
COPY Cargo.toml ./
# The lockfile from the first build, when there is one.
COPY Cargo.lock* ./
COPY src/ src/
ENV RUSTFLAGS="-C target-feature=+simd128"
RUN wasm-pack build --release --target web --out-name djvu --out-dir /out/pkg

# djvu-rs's licence, from the crate.
RUN mkdir -p /out/dist \
 && cp /out/pkg/djvu.js /out/pkg/djvu_bg.wasm Cargo.lock /out/dist/ \
 && cp /src/djvu-rs/LICENSE /out/dist/LICENSE \
 && sha256sum /out/dist/*

FROM scratch AS export
COPY --from=build /out/dist/ /