# The frontend is built and published separately; override to pin a version.
ARG FRONTEND_IMAGE=gitea.sanplex.xyz/sansan/musicfrontend:latest

# Stage 1: Build the backend on the build machine and cross-compile for the target platform,
# so multi-platform builds need no emulation.
FROM --platform=$BUILDPLATFORM golang:1.25-alpine AS build
ARG TARGETOS TARGETARCH
WORKDIR /app
COPY go.mod go.sum ./
RUN --mount=type=cache,target=/go/pkg/mod go mod download
COPY cmd/ ./cmd/
COPY internal/ ./internal/
RUN --mount=type=cache,target=/go/pkg/mod --mount=type=cache,target=/root/.cache/go-build \
    go tool templ generate
RUN --mount=type=cache,target=/go/pkg/mod --mount=type=cache,target=/root/.cache/go-build \
    CGO_ENABLED=0 GOOS=$TARGETOS GOARCH=$TARGETARCH \
    go build -trimpath -ldflags="-s -w" -tags timetzdata -o main ./cmd

# Stage 2: Frontend static files (the same for every platform)
FROM --platform=$BUILDPLATFORM ${FRONTEND_IMAGE} AS frontend
# Empty API_HOSTNAME makes the frontend use relative paths
RUN echo "window.__RUNTIME_CONFIG__ = { API_HOSTNAME: '' };" > /usr/share/nginx/html/config.js

# Stage 3: Final image. No RUN steps here, so no emulation is needed for other architectures.
FROM alpine:3.22
COPY --from=build /etc/ssl/certs/ca-certificates.crt /etc/ssl/certs/
WORKDIR /app
COPY --from=build /app/main .
COPY --from=frontend /usr/share/nginx/html /frontend
COPY ./songs/ ./songs/

# The music volume must be readable by uid 1000, and writable for the .id file cleanup during sync.
USER 1000:1000
EXPOSE 8080
VOLUME /sorted
VOLUME /characters

# Required: DB_HOST, DB_PORT, DB_USERNAME, DB_PASSWORD, DB_NAME, MUSIC_PATH, CHARACTERS_PATH
ENV PORT=8080

CMD ["./main"]