/*
Copyright (c) 2013 Microsoft Corporation. All rights reserved.
Released under Apache 2.0 license as described in the file LICENSE.

Author: Leonardo de Moura
*/
#include "lean_elaborator_exception.h"
#include "lean_elaborator.h"

namespace lean {
format pp(formatter fmt, context const & ctx, std::vector<expr> const & exprs, std::vector<expr> const & types, options const & opts) {
    unsigned indent = get_pp_indent(opts);
    lean_assert(exprs.size() == types.size());
    auto it1 = exprs.begin();
    auto it2 = types.begin();
    format r;
    for (; it1 != exprs.end(); ++it1, ++it2) {
        r += nest(indent, compose(line(), group(format{fmt(ctx, *it1, false, opts), space(), colon(),
                                                       nest(indent, format{line(), fmt(ctx, *it2, false, opts)})})));
    }
    return r;
}

format pp_elaborator_state(formatter fmt, elaborator const & elb, options const & opts) {
    unsigned indent     = get_pp_indent(opts);
    format r;
    if (elb.has_constraints()) {
        format elb_fmt  = elb.pp(fmt, opts);
        r += compose(line(), format("Elaborator state"));
        r += nest(indent, compose(line(), elb_fmt));
    }
    return r;
}

format pp(formatter fmt, elaborator_exception const & ex, options const & opts) {
    unsigned indent = get_pp_indent(opts);
    context const & ctx = ex.get_context();
    if (overload_exception const * _ex = dynamic_cast<overload_exception const *>(&ex)) {
        format r;
        r += format{format(ex.what()), line(), format("Candidates:")};
        r += pp(fmt, ctx, _ex->get_fs(), _ex->get_f_types(), opts);
        r += format{line(), format("Arguments:")};
        r += pp(fmt, ctx, _ex->get_args(), _ex->get_arg_types(), opts);
        return r;
    } else if (unification_app_mismatch_exception const * _ex = dynamic_cast<unification_app_mismatch_exception const *>(&ex)) {
        unsigned indent     = get_pp_indent(opts);
        auto const & elb    = _ex->get_elaborator();
        auto const & ctx    = _ex->get_context();
        expr const & app    = _ex->get_expr();
        auto const & args   = _ex->get_args();
        auto const & types  = _ex->get_types();
        auto args_it        = args.begin();
        auto types_it       = types.begin();
        format app_fmt      = fmt(ctx, app, false, opts);
        format r            = format{format(_ex->what()), nest(indent, compose(line(), app_fmt))};
        format fun_type_fmt = fmt(ctx, *types_it, false, opts);
        r += compose(line(), format("Function type:"));
        r += nest(indent, compose(line(), fun_type_fmt));
        ++args_it;
        ++types_it;
        if (args.size() > 2)
            r += compose(line(), format("Arguments types:"));
        else
            r += compose(line(), format("Argument type:"));
        for (; args_it != args.end(); ++args_it, ++types_it) {
            format arg_fmt    = fmt(ctx, *args_it, false, opts);
            format type_fmt   = fmt(ctx, *types_it, false, opts);
            r += nest(indent, compose(line(), group(format{arg_fmt, space(), colon(), nest(indent, format{line(), type_fmt})})));
        }
        r += pp_elaborator_state(fmt, elb, opts);
        return r;
    } else if (unification_type_mismatch_exception const * _ex = dynamic_cast<unification_type_mismatch_exception const *>(&ex)) {
        unsigned indent     = get_pp_indent(opts);
        auto const & elb    = _ex->get_elaborator();
        auto const & ctx    = _ex->get_context();
        expr const & e      = _ex->get_expr();
        expr const & p      = _ex->get_processed_expr();
        expr const & exp    = _ex->get_expected_type();
        expr const & given  = _ex->get_given_type();
        format r            = format{format(_ex->what()), nest(indent, compose(line(), fmt(ctx, e, false, opts)))};
        if (p != e) {
            r += compose(line(), format("Term after elaboration:"));
            r += nest(indent, compose(line(), fmt(ctx, p, false, opts)));
        }
        r += compose(line(), format("Expected type:"));
        r += nest(indent, compose(line(), fmt(ctx, exp, false, opts)));
        if (given) {
            r += compose(line(), format("Got:"));
            r += nest(indent, compose(line(), fmt(ctx, given, false, opts)));
        }
        r += pp_elaborator_state(fmt, elb, opts);
        return r;
    } else {
        auto const & elb = ex.get_elaborator();
        format expr_fmt  = fmt(ctx, ex.get_expr(), false, opts);
        format r = format{format(ex.what()), space(), format("at term"), nest(indent, compose(line(), expr_fmt))};
        r += pp_elaborator_state(fmt, elb, opts);
        return r;
    }
}

regular const & operator<<(regular const & out, elaborator_exception const & ex) {
    options const & opts = out.m_state.get_options();
    out.m_state.get_regular_channel().get_stream() << mk_pair(pp(out.m_state.get_formatter(), ex, opts), opts);
    return out;
}

diagnostic const & operator<<(diagnostic const & out, elaborator_exception const & ex) {
    options const & opts = out.m_state.get_options();
    out.m_state.get_diagnostic_channel().get_stream() << mk_pair(pp(out.m_state.get_formatter(), ex, opts), opts);
    return out;
}
}