#include "config.h"

#include "buffers.h"
#include "ccdjit.h"
#include "common.h"
#include "ecex.h"
#include "eval.h"
#include "path.h"

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

typedef int (*ecex_config_init_fn)(ecex_t *ed);

typedef struct host_symbol {
    const char *name;
    void *addr;
} host_symbol_t;

void ecex_print_ccdjit_error(ccdjit_context *ctx) {
    const ccdjit_diagnostic *diag = ccdjit_context_last_error(ctx);

    if (!diag) {
        fprintf(stderr, "ccdjit: unknown error\n");
        return;
    }

    fprintf(stderr,
            "ccdjit error [%s] %s:%d:%d: %s\n",
            diag->phase ? diag->phase : "?",
            diag->filename ? diag->filename : "<input>",
            diag->line,
            diag->column,
            diag->message ? diag->message : "(no message)");

    if (diag->source_line) fprintf(stderr, "%s\n", diag->source_line);
    if (diag->caret_line) fprintf(stderr, "%s\n", diag->caret_line);
}

#define HOST_SYMBOL(fn) { #fn, (void *)(fn) }

static const host_symbol_t host_symbols[] = {
    HOST_SYMBOL(ecex_current_buffer),
    HOST_SYMBOL(ecex_create_buffer),
    HOST_SYMBOL(ecex_find_buffer),
    HOST_SYMBOL(ecex_switch_buffer),
    HOST_SYMBOL(ecex_next_buffer),
    HOST_SYMBOL(ecex_previous_buffer),
    HOST_SYMBOL(ecex_current_window),
    HOST_SYMBOL(ecex_window_count),
    HOST_SYMBOL(ecex_split_window_vertically),
    HOST_SYMBOL(ecex_split_window_horizontally),
    HOST_SYMBOL(ecex_other_window),
    HOST_SYMBOL(ecex_previous_window),
    HOST_SYMBOL(ecex_delete_window),
    HOST_SYMBOL(ecex_delete_other_windows),
    HOST_SYMBOL(ecex_kill_buffer),
    HOST_SYMBOL(ecex_kill_buffer_force),
    HOST_SYMBOL(ecex_has_modified_buffers),
    HOST_SYMBOL(ecex_validate_bindings),
    HOST_SYMBOL(ecex_config_alloc),
    HOST_SYMBOL(ecex_config_calloc),
    HOST_SYMBOL(ecex_config_free),
    HOST_SYMBOL(ecex_time_seconds),
    HOST_SYMBOL(ecex_log),
    HOST_SYMBOL(ecex_logf),
    HOST_SYMBOL(ecex_log_group_begin),
    HOST_SYMBOL(ecex_log_group_end),
    HOST_SYMBOL(ecex_log_int),
    HOST_SYMBOL(ecex_log_double),
    HOST_SYMBOL(ecex_log_ptr),
    HOST_SYMBOL(ecex_log_flush),
    HOST_SYMBOL(ecex_mem_zero),
    HOST_SYMBOL(ecex_i32_get),
    HOST_SYMBOL(ecex_i32_set),
    HOST_SYMBOL(ecex_prng_next_bounded),
    HOST_SYMBOL(ecex_random_bounded),
    HOST_SYMBOL(ecex_plugin_register),
    HOST_SYMBOL(ecex_plugin_require),
    HOST_SYMBOL(ecex_plugin_find),
    HOST_SYMBOL(ecex_plugin_id),
    HOST_SYMBOL(ecex_plugin_slot_alloc),
    HOST_SYMBOL(ecex_plugin_slot_get),
    HOST_SYMBOL(ecex_plugin_slot_free),
    HOST_SYMBOL(ecex_plugin_slot_set_export_flags),
    HOST_SYMBOL(ecex_plugin_slot_read_exported),
    HOST_SYMBOL(ecex_plugin_slot_i32_get),
    HOST_SYMBOL(ecex_plugin_slot_i32_set),
    HOST_SYMBOL(ecex_plugin_slot_i32_get_2d),
    HOST_SYMBOL(ecex_plugin_slot_i32_set_2d),
    HOST_SYMBOL(ecex_plugin_slot_i32_get_scalar),
    HOST_SYMBOL(ecex_plugin_slot_i32_set_scalar),
    HOST_SYMBOL(ecex_plugin_object_alloc),
    HOST_SYMBOL(ecex_plugin_object_calloc),
    HOST_SYMBOL(ecex_plugin_object_free),
    HOST_SYMBOL(ecex_plugin_object_valid),
    HOST_SYMBOL(ecex_plugin_object_i32_get),
    HOST_SYMBOL(ecex_plugin_object_i32_set),
    HOST_SYMBOL(ecex_plugin_object_ptr_get),
    HOST_SYMBOL(ecex_plugin_object_ptr_set),
    HOST_SYMBOL(ecex_plugin_text_set),
    HOST_SYMBOL(ecex_plugin_text_set_from_buffer_title),
    HOST_SYMBOL(ecex_plugin_text_free),
    HOST_SYMBOL(ecex_plugin_text_free_all),
    HOST_SYMBOL(ecex_plugin_text_get_drawable),
    HOST_SYMBOL(ecex_buffer_text_len),
    HOST_SYMBOL(ecex_buffer_scroll_line_index),
    HOST_SYMBOL(ecex_buffer_line_count_int),
    HOST_SYMBOL(ecex_buffer_line_copy_text),
    HOST_SYMBOL(ecex_markdown_draw_buffer_line_i),
    HOST_SYMBOL(ecex_markdown_body_y_px),
    HOST_SYMBOL(ecex_draw_context_height_px),
    HOST_SYMBOL(ecex_draw_context_line_height_px),
    HOST_SYMBOL(ecex_plugin_file_handler_register),
    HOST_SYMBOL(ecex_plugin_file_handlers_run),

    HOST_SYMBOL(ecex_config_register_commands),
    HOST_SYMBOL(ecex_config_bind_keys),
    HOST_SYMBOL(ecex_config_bind_mode_keys),
    HOST_SYMBOL(ecex_config_define_modes),
    HOST_SYMBOL(ecex_apply_theme),
    HOST_SYMBOL(ecex_register_command),
    HOST_SYMBOL(ecex_execute_command),
    HOST_SYMBOL(ecex_add_command_hook),
    HOST_SYMBOL(ecex_remove_command_hook),
    HOST_SYMBOL(ecex_add_prefix_hook),
    HOST_SYMBOL(ecex_remove_prefix_hook),
    HOST_SYMBOL(ecex_notify_prefix_hooks),
    HOST_SYMBOL(ecex_add_buffer_hook),
    HOST_SYMBOL(ecex_remove_buffer_hook),
    HOST_SYMBOL(ecex_notify_buffer_hooks),
    HOST_SYMBOL(ecex_message),
    HOST_SYMBOL(ecex_dependency_available),
    HOST_SYMBOL(ecex_plugin_require_dependency),
    HOST_SYMBOL(ecex_add_completion_provider),
    HOST_SYMBOL(ecex_add_word_completion_provider),
    HOST_SYMBOL(ecex_define_word_completion_provider),
    HOST_SYMBOL(ecex_completion_provider_add_word),
    HOST_SYMBOL(ecex_completion_provider_add_words),
    HOST_SYMBOL(ecex_completion_provider_set_detail),
    HOST_SYMBOL(ecex_add_clangd_completion_provider),
    HOST_SYMBOL(ecex_remove_completion_provider),
    HOST_SYMBOL(ecex_buffer_identifier_prefix),
    HOST_SYMBOL(ecex_complete_at_point),
    HOST_SYMBOL(ecex_bind_key),
    HOST_SYMBOL(ecex_lookup_key),
    HOST_SYMBOL(ecex_define_major_mode),
    HOST_SYMBOL(ecex_major_mode_by_name),
    HOST_SYMBOL(ecex_major_mode_name),
    HOST_SYMBOL(ecex_buffer_set_major_mode),
    HOST_SYMBOL(ecex_buffer_set_major_mode_by_name),
    HOST_SYMBOL(ecex_buffer_major_mode_name),
    HOST_SYMBOL(ecex_bind_mode_key),
    HOST_SYMBOL(ecex_lookup_key_for_buffer),
    HOST_SYMBOL(ecex_key_sequence_has_prefix_for_buffer),
    HOST_SYMBOL(ecex_describe_key_prefix),
    HOST_SYMBOL(ecex_auto_set_major_mode),
    HOST_SYMBOL(ecex_list_commands),
    HOST_SYMBOL(ecex_list_buffers),
    HOST_SYMBOL(ecex_create_interactive_buffer),
    HOST_SYMBOL(ecex_interactive_append_line),
    HOST_SYMBOL(ecex_interactive_activate_current_line),
    HOST_SYMBOL(ecex_buffer_set_renderer),
    HOST_SYMBOL(ecex_buffer_clear_renderer),
    HOST_SYMBOL(ecex_buffer_has_renderer),
    HOST_SYMBOL(ecex_buffer_renderer_userdata),
    HOST_SYMBOL(ecex_buffer_set_mouse_handler),
    HOST_SYMBOL(ecex_buffer_clear_mouse_handler),
    HOST_SYMBOL(ecex_buffer_has_mouse_handler),
    HOST_SYMBOL(ecex_buffer_mouse_userdata),
    HOST_SYMBOL(ecex_buffer_set_animation),
    HOST_SYMBOL(ecex_buffer_set_animation_ms),
    HOST_SYMBOL(ecex_buffer_clear_animation),
    HOST_SYMBOL(ecex_buffer_is_animating),
    HOST_SYMBOL(ecex_buffer_animation_userdata),
    HOST_SYMBOL(ecex_tick_animations),
    HOST_SYMBOL(ecex_buffer_replace_text),
    HOST_SYMBOL(ecex_buffer_set_modified),
    HOST_SYMBOL(ecex_draw_set_color),
    HOST_SYMBOL(ecex_draw_rect),
    HOST_SYMBOL(ecex_draw_rect_outline),
    HOST_SYMBOL(ecex_draw_line),
    HOST_SYMBOL(ecex_draw_text),
    HOST_SYMBOL(ecex_draw_text_aligned),
    HOST_SYMBOL(ecex_draw_text_width),
    HOST_SYMBOL(ecex_draw_color_rgba8_i),
    HOST_SYMBOL(ecex_draw_rect_i),
    HOST_SYMBOL(ecex_draw_rect_outline_i),
    HOST_SYMBOL(ecex_draw_line_i),
    HOST_SYMBOL(ecex_draw_text_i),
    HOST_SYMBOL(ecex_draw_plugin_text_i),
    HOST_SYMBOL(ecex_draw_plugin_text_rect_i),
    HOST_SYMBOL(ecex_draw_markdown_canvas_i),
    HOST_SYMBOL(ecex_draw_markdown_text_i),
    HOST_SYMBOL(ecex_draw_markdown_canvas_auto_i),
    HOST_SYMBOL(ecex_draw_markdown_line_auto_i),
    HOST_SYMBOL(ecex_draw_label_i),
    HOST_SYMBOL(ecex_draw_stat_i),
    HOST_SYMBOL(ecex_draw_tetris_preview_i),
    HOST_SYMBOL(ecex_draw_rgba),
    HOST_SYMBOL(ecex_find_file),
    HOST_SYMBOL(ecex_save_current_buffer),
    HOST_SYMBOL(ecex_write_current_buffer),
    HOST_SYMBOL(ecex_compile),
    HOST_SYMBOL(ecex_grep),
    HOST_SYMBOL(ecex_rerun_compile),
    HOST_SYMBOL(ecex_rerun_grep),
    HOST_SYMBOL(ecex_next_interactive_action),
    HOST_SYMBOL(ecex_previous_interactive_action),
    HOST_SYMBOL(ecex_indent_line_to),
    HOST_SYMBOL(ecex_comment_region),
    HOST_SYMBOL(ecex_uncomment_region),
    HOST_SYMBOL(ecex_request_prompt),
    HOST_SYMBOL(ecex_clear_prompt_request),
    HOST_SYMBOL(ecex_complete_command),

    HOST_SYMBOL(ecex_path_copy),
    HOST_SYMBOL(ecex_path_expand_user),
    HOST_SYMBOL(ecex_path_join),
    HOST_SYMBOL(ecex_path_dirname),
    HOST_SYMBOL(ecex_path_basename_dup),
    HOST_SYMBOL(ecex_path_normalize),
    HOST_SYMBOL(ecex_path_is_dir),
    HOST_SYMBOL(ecex_path_is_file),
    HOST_SYMBOL(ecex_path_exists),
    HOST_SYMBOL(ecex_path_file_size),
    HOST_SYMBOL(ecex_path_is_image),
    HOST_SYMBOL(ecex_path_is_previewable_image),
    HOST_SYMBOL(ecex_path_is_video),
    HOST_SYMBOL(ecex_path_is_media),
    HOST_SYMBOL(ecex_path_cwd),
    HOST_SYMBOL(ecex_media_open),
    HOST_SYMBOL(ecex_media_toggle_playback),
    HOST_SYMBOL(ecex_eval_source),
    HOST_SYMBOL(ecex_eval_current_buffer),
    HOST_SYMBOL(ecex_eval_current_line),
    HOST_SYMBOL(ecex_eval_current_region),
    HOST_SYMBOL(ecex_eval_file),
    HOST_SYMBOL(ecex_eval_rerun_last),

    HOST_SYMBOL(ecex_set_font),
    HOST_SYMBOL(ecex_get_font_size),
    HOST_SYMBOL(ecex_set_font_size),
    HOST_SYMBOL(ecex_adjust_font_size),
    HOST_SYMBOL(ecex_set_bg_color),
    HOST_SYMBOL(ecex_set_fg_color),
    HOST_SYMBOL(ecex_set_status_bg_color),
    HOST_SYMBOL(ecex_set_status_fg_color),
    HOST_SYMBOL(ecex_set_status_border_color),
    HOST_SYMBOL(ecex_set_cursor_color),
    HOST_SYMBOL(ecex_set_region_bg_color),
    HOST_SYMBOL(ecex_set_minibuffer_bg_color),
    HOST_SYMBOL(ecex_set_minibuffer_fg_color),
    HOST_SYMBOL(ecex_set_completion_fg_color),
    HOST_SYMBOL(ecex_set_completion_enabled),
    HOST_SYMBOL(ecex_set_interactive_highlight_bg_color),
    HOST_SYMBOL(ecex_set_interactive_highlight_fg_color),
    HOST_SYMBOL(ecex_set_current_line_bg_color),
    HOST_SYMBOL(ecex_set_search_bg_color),
    HOST_SYMBOL(ecex_set_line_numbers_enabled),
    HOST_SYMBOL(ecex_set_current_line_enabled),

    HOST_SYMBOL(buffer_clear),
    HOST_SYMBOL(buffer_set_text),
    HOST_SYMBOL(buffer_insert),
    HOST_SYMBOL(buffer_insert_at),
    HOST_SYMBOL(buffer_append),
    HOST_SYMBOL(buffer_prepend),
    HOST_SYMBOL(buffer_insert_char),
    HOST_SYMBOL(buffer_insert_char_at),
    HOST_SYMBOL(buffer_delete_range),
    HOST_SYMBOL(buffer_delete_selection),
    HOST_SYMBOL(buffer_replace_selection),
    HOST_SYMBOL(buffer_backspace),
    HOST_SYMBOL(buffer_delete_forward),
    HOST_SYMBOL(buffer_kill_line),

    HOST_SYMBOL(buffer_set_point),
    HOST_SYMBOL(buffer_move_left),
    HOST_SYMBOL(buffer_move_right),
    HOST_SYMBOL(buffer_move_up),
    HOST_SYMBOL(buffer_move_down),
    HOST_SYMBOL(buffer_move_word_left),
    HOST_SYMBOL(buffer_move_word_right),
    HOST_SYMBOL(buffer_move_beginning_of_line),
    HOST_SYMBOL(buffer_move_end_of_line),
    HOST_SYMBOL(buffer_move_beginning_of_buffer),
    HOST_SYMBOL(buffer_move_end_of_buffer),

    HOST_SYMBOL(buffer_set_mark),
    HOST_SYMBOL(buffer_clear_mark),
    HOST_SYMBOL(buffer_has_selection),
    HOST_SYMBOL(buffer_selection_range),

    HOST_SYMBOL(buffer_line_start_at),
    HOST_SYMBOL(buffer_line_end_at),
    HOST_SYMBOL(buffer_current_line_start),
    HOST_SYMBOL(buffer_current_line_end),
    HOST_SYMBOL(buffer_current_column),
    HOST_SYMBOL(buffer_current_line_number),
    HOST_SYMBOL(buffer_line_count),
    HOST_SYMBOL(buffer_substring),
    HOST_SYMBOL(buffer_current_line_copy),

    HOST_SYMBOL(buffer_load_file),
    HOST_SYMBOL(buffer_save),
    HOST_SYMBOL(buffer_save_as),
    HOST_SYMBOL(buffer_set_interactive),
    HOST_SYMBOL(buffer_is_interactive),
    HOST_SYMBOL(buffer_clear_interactive_actions),
    HOST_SYMBOL(buffer_add_interactive_action),
    HOST_SYMBOL(buffer_interactive_action_at_line),
};

#undef HOST_SYMBOL

int ecex_register_host_symbols(ccdjit_context *ctx) {
    for (size_t i = 0; i < ECEX_ARRAY_LEN(host_symbols); i++) {
        if (ccdjit_context_register_symbol(ctx,
                                           host_symbols[i].name,
                                           host_symbols[i].addr) != 0) {
            fprintf(stderr, "ecex: failed to register symbol: %s\n", host_symbols[i].name);
            ecex_print_ccdjit_error(ctx);
            return ECEX_ERR;
        }
    }

    return ECEX_OK;
}

static int add_include_path(ccdjit_context *ctx, const char *path) {
    if (ccdjit_context_add_include_path(ctx, path) == 0) return ECEX_OK;

    fprintf(stderr, "ecex: failed to add include path: %s\n", path);
    ecex_print_ccdjit_error(ctx);
    return ECEX_ERR;
}

int ecex_add_ccdjit_include_paths(ccdjit_context *ctx) {
    if (add_include_path(ctx, "include") != ECEX_OK) return ECEX_ERR;
    if (add_include_path(ctx, "../include") != ECEX_OK) return ECEX_ERR;

    const char *env_include = getenv("ECEX_INCLUDE");
    if (env_include && env_include[0]) {
        if (add_include_path(ctx, env_include) != ECEX_OK) return ECEX_ERR;
    }

    return ECEX_OK;
}

static int ccdjit_type_is_int(ccdjit_type_info type) {
    return type.has_type &&
           type.base == CCDJIT_TYPE_INT &&
           type.pointer_level == 0;
}

static int ccdjit_type_is_pointer(ccdjit_type_info type) {
    return type.has_type && type.pointer_level == 1;
}

static ecex_config_init_fn ecex_config_init_symbol(ccdjit_context *ctx,
                                                   ccdjit_module *module,
                                                   const char *path) {
    void *symbol = ccdjit_module_symbol(module, "ecex_config_init");
    if (!symbol) return NULL;

    ccdjit_symbol_info info;
    memset(&info, 0, sizeof(info));
    if (ccdjit_module_symbol_info(module, "ecex_config_init", &info) == 0 &&
        info.has_signature) {
        ccdjit_type_info param;
        memset(&param, 0, sizeof(param));

        if (info.kind != CCDJIT_SYMBOL_FUNCTION ||
            !ccdjit_type_is_int(info.return_type) ||
            info.parameter_count != 1 ||
            info.is_variadic ||
            ccdjit_module_function_parameter_type(module, "ecex_config_init", 0, &param) != 0 ||
            !ccdjit_type_is_pointer(param)) {
            fprintf(stderr,
                    "ecex: invalid config signature in %s; expected int ecex_config_init(ecex_t *ed)\n",
                    path ? path : "<config>");
            return NULL;
        }
    } else if (ctx) {
        const ccdjit_diagnostic *diag = ccdjit_context_last_error(ctx);
        if (diag && diag->code != CCDJIT_DIAG_NONE) {
            ecex_print_ccdjit_error(ctx);
        }
    }

    return (ecex_config_init_fn)symbol;
}

int ecex_load_c_config(ecex_t *ed, const char *path) {
    if (!ed || !path) return ECEX_ERR;

    ccdjit_context *ctx = ccdjit_context_new(NULL);
    if (!ctx) {
        fprintf(stderr, "ecex: failed to create ccdjit context\n");
        return ECEX_ERR;
    }

    if (ecex_add_ccdjit_include_paths(ctx) != ECEX_OK || ecex_register_host_symbols(ctx) != ECEX_OK) {
        ccdjit_context_free(ctx);
        return ECEX_ERR;
    }

    ccdjit_module *module = NULL;
    if (ccdjit_compile_file_module(ctx, path, &module) != 0) {
        fprintf(stderr, "ecex: failed to compile config: %s\n", path);
        ecex_print_ccdjit_error(ctx);
        ccdjit_context_free(ctx);
        return ECEX_ERR;
    }

    ecex_config_init_fn init = ecex_config_init_symbol(ctx, module, path);

    if (!init) {
        fprintf(stderr, "ecex: config missing function: ecex_config_init\n");
        ecex_print_ccdjit_error(ctx);
        ccdjit_module_free(module);
        ccdjit_context_free(ctx);
        return ECEX_ERR;
    }

    int result = init(ed);
    if (result != 0) {
        fprintf(stderr, "ecex: config init failed with code: %d\n", result);
        /* Config init may have registered hooks/renderers before returning an
         * error. Keep the module alive so rollback can call any JIT-owned
         * destructors safely. */
        if (ecex_keep_jit_module(ed, module) != ECEX_OK) {
            fprintf(stderr, "ecex: failed to retain failed config module; leaving it mapped for cleanup safety\n");
        }
        ccdjit_context_free(ctx);
        return ECEX_ERR;
    }

    if (ecex_keep_jit_module(ed, module) != ECEX_OK) {
        fprintf(stderr, "ecex: failed to retain config module\n");
        ccdjit_module_free(module);
        ccdjit_context_free(ctx);
        return ECEX_ERR;
    }

    if (ecex_set_config_path(ed, path) != ECEX_OK) {
        fprintf(stderr, "ecex: failed to remember config path: %s\n", path);
        ccdjit_context_free(ctx);
        return ECEX_ERR;
    }

    ccdjit_context_free(ctx);
    fprintf(stderr, "ecex: loaded config: %s\n", path);
    return ECEX_OK;
}