#include <scc_ir2sccf.h>

static inline void scc_ir_sym_to_sccf_sym(const scc_cfg_symbol_t *symbol,
                                          sccf_sym_t *sym) {
    switch (symbol->kind) {
    case SCC_CFG_SYMBOL_KIND_DATA:
        sym->sccf_sym_type = SCCF_SYM_TYPE_DATA;
        break;
    case SCC_CFG_SYMBOL_KIND_FUNC:
        sym->sccf_sym_type = SCCF_SYM_TYPE_FUNC;
        break;
    case SCC_CFG_SYMBOL_KIND_EXTERN:
        sym->sccf_sym_type = SCCF_SYM_TYPE_EXTERN;
        break;
    }

    switch (symbol->linkage) {
    case SCC_CFG_SYMBOL_LINK_GLOABL:
        sym->sccf_sym_bind = SCCF_SYM_BIND_GLOBAL;
        break;
    case SCC_CFG_SYMBOL_LINK_LOCAL:
        sym->sccf_sym_bind = SCCF_SYM_BIND_LOCAL;
        break;
    default:
        break;
    }
}

static inline void scc_ir_symbol_to_sect_data(const scc_cfg_symbol_t *symbol,
                                              sccf_sect_data_t *sect_data) {
    // scc_vec_foreach(value->data.const_array.fields, j) {
    //     scc_vec_push(ctx->sect_data,
    //                  scc_vec_at(value->data.const_array.fields, j));
    // }
}

void scc_ir2sccf(sccf_builder_t *builder, scc_mir_module_t *mir_module) {
    // mir_module->symbol_metas
    // mir_module->cfg_module.funcs
    sccf_builder_init(builder);
    sccf_sect_data_t sect_data;
    scc_vec_init(sect_data);

    scc_vec_foreach(mir_module->cfg_module.symbols, i) {
        scc_cfg_symbol_t *symbol =
            &scc_vec_at(mir_module->cfg_module.symbols, i);

        if (symbol->name == nullptr) {
            LOG_ERROR("Symbol name is null");
            continue;
        }

        sccf_sym_t sym = (sccf_sym_t){
            .sccf_sect_offset = scc_vec_size(sect_data),
            .sccf_sym_size =
                4, // FIXME on windows using rel32, on linux using ?
        };

        scc_ir_sym_to_sccf_sym(symbol, &sym);
        scc_ir_symbol_to_sect_data(symbol, &sect_data);

        usize sym_idx = sccf_builder_add_symbol(builder, symbol->name, &sym);
        Assert(sym_idx != 0);
    }

    sccf_sect_data_t sect_code = {0};
    scc_vec_init(sect_code);
    scc_mcode_t mcode = {0};
    scc_mcode_init(&mcode, SCC_MCODE_ARCH_X86_64);
    scc_vec_foreach(mir_module->cfg_module.funcs, i) {
        if (i == 0)
            continue;
        scc_mir_func_t *func = &scc_vec_at(mir_module->cfg_module.funcs, i);

        sccf_sym_t *sym = sccf_builder_get_symbol_unsafe(builder, func->name);
        Assert(sym != nullptr);
        sym->sccf_sect_offset = scc_vec_size(mcode.mcode);

        scc_vec_foreach(func->bblocks, i) {
            scc_cfg_bblock_id_t id = scc_vec_at(func->bblocks, i);
            const scc_cfg_bblock_t *bb =
                scc_cfg_module_unsafe_get_bblock(&mir_module->cfg_module, id);
            scc_mir_instr_vec_t *instrs = SCC_MIR_BBLOCK_VALUES(bb);
            scc_vec_foreach(*instrs, i) {
                const scc_mir_instr_t *ins = &scc_vec_at(*instrs, i);
                // FIXME reloc symbol needed
                scc_ir2mcode_emit_instr(&mcode, ins);
            }
        }
    }
    scc_vec_unsafe_from_buffer(sect_code, scc_vec_unsafe_get_data(mcode.mcode),
                               scc_vec_size(mcode.mcode));

    // u8 *buf = scc_vec_unsafe_get_data(ctx->sect_mcode.mcode);
    // scc_vec_foreach(ctx->builder->relocs, i) {
    //     sccf_reloc_t *reloc = &scc_vec_at(ctx->builder->relocs, i);
    //     if (reloc->sym_idx == 0) {
    //         Panic("relocate to an invalid symbol");
    //     }
    //     sccf_sym_t *sym = &scc_vec_at(ctx->builder->symtab, reloc->sym_idx);
    //     if (sym->sccf_sym_type != SCCF_SYM_TYPE_EXTERN) {
    //         Assert(reloc->reloc_type == SCCF_RELOC_TYPE_REL);

    //         if (sym->sccf_sect_type == SCCF_SECT_CODE &&
    //             sym->sccf_sym_type == SCCF_SYM_TYPE_FUNC) {
    //             i64 target_off = sym->sccf_sect_offset;
    //             i64 next_off = reloc->offset + reloc->addend;
    //             i32 rel = (i32)(target_off - next_off);
    //             // FIXME 写入到指令的偏移字段（小端）
    //             *(i32 *)(&buf[reloc->offset]) = rel;

    //             reloc->reloc_type = SCCF_RELOC_TYPE_EMPTY;
    //         }
    //     }
    // }

    sccf_builder_add_text_section(builder, &sect_code);
    sccf_builder_add_data_section(builder, &sect_data);
}