// TODO: just let compiler infer error set through recursive calls
// depends on: https://github.com/ziglang/zig/issues/2971

// This code is heavily insprired by Devine's implementation in C:
// https://github.com/hundredrabbits/100r.co/blob/main/src/main.c and his
// personal site https://github.com/XXIIVV/Oscean

const Context = @import("Context.zig");
const os = @import("os.zig");

const std = @import("std");

const log = std.log.scoped(.rbc);

// tune std.log options
pub const std_options = std.Options{
    .log_level = if (@import("builtin").mode == .Debug) .debug else .info,
};

const Cli = struct {
    const Defaults = struct {
        const ROOT: []const u8 = "src/inc";
        const SITE: []const u8 = "site";
    };

    fn run(init: std.process.Init, ctx: *Context) !void {
        var argv = init.minimal.args.iterate();

        _ = argv.skip(); // skip command name

        if (argv.inner.remaining.len == 0) {
            return Cli.helpCmd();
        }

        while (argv.next()) |arg| {
            if (std.mem.eql(u8, arg, "help")) {
                return Cli.helpCmd();
            } else if (std.mem.eql(u8, arg, "gen")) {
                try Cli.genCmd(init, &argv, ctx);
            } else if (std.mem.eql(u8, arg, "md")) {
                try Cli.mdCmd(ctx, &argv);
            } else if (std.mem.eql(u8, arg, "watch")) {
                try Cli.watchCmd(init, &argv);
            } else if (std.mem.eql(u8, arg, "serve")) {
                try Cli.serveCmd(init, &argv);
            } else {
                return Cli.helpCmd();
            }
        }
    }

    fn helpCmd() void {
        std.debug.print("usage: rbc COMMAND\n\n", .{});
        std.debug.print(" rbc gen ROOT SITE [force=true]\n", .{});
        std.debug.print(" rbc watch\n", .{});
        std.debug.print(" rbc serve\n", .{});
        std.debug.print("\n", .{});
    }

    fn genCmd(init: std.process.Init, argv: *std.process.Args.Iterator, ctx: *Context) !void {
        const root = argv.next() orelse Cli.Defaults.ROOT;
        const site = argv.next() orelse Cli.Defaults.SITE;
        const force = blk: {
            const forcearg = argv.next();
            if (forcearg != null and std.mem.eql(u8, forcearg.?, "force=true")) {
                break :blk true;
            } else {
                break :blk false;
            }
        };
        log.info("root = {s}", .{root});
        log.info("site = {s}", .{site});
        try ctx.index(try std.Io.Dir.cwd().openDir(init.io, root, .{ .iterate = true }));
        try ctx.render(try std.Io.Dir.cwd().createDirPathOpen(init.io, site, .{}), force);
    }

    fn mdCmd(init: std.process.Init, argv: *std.process.Args.Iterator, ctx: *Context) !void {
        const root = argv.next() orelse Cli.Defaults.ROOT;
        log.info("root = {s}", .{root});

        try os.shell(init.io,
            \\pandoc --from markdown+wikilinks_title_after_pipe+autolink_bare_uris --to html5 --lua-filter preproc.lua --strip-comments --output=-
        , .{ .environ_map = &env_map, .cwd = .{ .path = root } });
    }

    fn watchCmd(init: std.process.Init, argv: *std.process.Args.Iterator) !void {
        const root = argv.next() orelse Cli.Defaults.ROOT;
        const site = argv.next() orelse Cli.Defaults.SITE;

        const exePath = blk: {
            var buf: [std.os.linux.PATH_MAX]u8 = undefined;
            const n = try std.process.executablePath(init.io, &buf);
            break :blk buf[0..n];
        };
        const command = try std.fmt.allocPrint(init.gpa,
            \\find "{s}" -path '*.htm' -type f -print | entr -nc -dd -- "{s}" gen "{s}" "{s}"
        , .{ root, exePath, root, site });
        try os.shell(init.io, command, .{});
    }

    fn serveCmd(init: std.process.Init, argv: *std.process.Args.Iterator) !void {
        const root = argv.next() orelse ".";
        log.info("root = {s}", .{root});

        var env_map = try init.minimal.environ.createMap(init.gpa);
        defer env_map.deinit();
        try env_map.put("CADDY_HTTP_PORT", "1414");
        try env_map.put("CADDY_HOST", "localhost");

        if ((try std.Io.Dir.cwd().openDir(init.io, root, .{})).access(init.io, "Caddyfile", .{})) {
            try os.shell(init.io,
                \\caddy fmt --overwrite && caddy run --watch
            , .{ .environ_map = &env_map, .cwd = .{ .path = root } });
        } else |_| {
            try os.shell(init.io,
                \\caddy file-server --listen=$CADDY_HOST:$CADDY_HTTP_PORT
            , .{ .environ_map = &env_map, .cwd = .{ .path = root } });
        }
    }
};

pub fn main(init: std.process.Init) !void {
    var ctx = try Context.init(init.io, init.gpa);
    defer ctx.deinit();

    try Cli.run(init, &ctx);
}