#include <bshell/line-editor/core.h>
#include <bshell/line-editor/line-editor.h>
#include <bshell/line-editor/plugin.h>
#include <fx/collections/hashtable.h>
#include <fx/term/tty.h>

struct bshell_line_ed_core_p {
	bshell_line_ed_keybind *c_key_cursor_left;
	bshell_line_ed_keybind *c_key_cursor_right;
	bshell_line_ed_keybind *c_key_return;
	bshell_line_ed_keybind *c_key_eof;
	bshell_line_ed_keybind *c_key_generic;
	bshell_line_ed_keybind *c_key_backspace;

	fx_hashtable *c_data;
};

static void init(fx_object *obj, void *priv)
{
	struct bshell_line_ed_core_p *core = priv;
	core->c_data = fx_hashtable_create();
}

static void fini(fx_object *obj, void *priv)
{
	struct bshell_line_ed_core_p *core = priv;
	fx_hashtable_unref(core->c_data);
}

static struct bshell_line_ed_keybind_result delete_backward(
	bshell_line_ed *ed,
	fx_keycode key)
{
	return BSHELL_LINE_EDITOR_KEYBIND_RESULT(
		BSHELL_SUCCESS,
		BSHELL_LINE_EDITOR_KEYBIND_CONTINUE);
}

static struct bshell_line_ed_keybind_result cursor_left(
	bshell_line_ed *ed,
	fx_keycode key)
{
	bshell_line_ed_move_cursor(ed, -1);
	return BSHELL_LINE_EDITOR_KEYBIND_RESULT(
		BSHELL_SUCCESS,
		BSHELL_LINE_EDITOR_KEYBIND_CONTINUE);
}

static struct bshell_line_ed_keybind_result cursor_right(
	bshell_line_ed *ed,
	fx_keycode key)
{
	bshell_line_ed_move_cursor(ed, 1);
	return BSHELL_LINE_EDITOR_KEYBIND_RESULT(
		BSHELL_SUCCESS,
		BSHELL_LINE_EDITOR_KEYBIND_CONTINUE);
}

static struct bshell_line_ed_keybind_result eof_key(
	bshell_line_ed *ed,
	fx_keycode key)
{
	bshell_line_ed_set_eof(ed);
	return BSHELL_LINE_EDITOR_KEYBIND_RESULT(
		BSHELL_SUCCESS,
		BSHELL_LINE_EDITOR_KEYBIND_CONTINUE);
}

static struct bshell_line_ed_keybind_result return_key(
	bshell_line_ed *ed,
	fx_keycode key)
{
	bshell_line_ed_set_done(ed);
	fx_string *buf = bshell_line_ed_get_buffer(ed);
	fx_string_append_c(buf, '\n');
	return BSHELL_LINE_EDITOR_KEYBIND_RESULT(
		BSHELL_SUCCESS,
		BSHELL_LINE_EDITOR_KEYBIND_CONTINUE);
}

static struct bshell_line_ed_keybind_result backspace(
	bshell_line_ed *ed,
	fx_keycode key)
{
	fx_string *buf = bshell_line_ed_get_buffer(ed);
	unsigned long cursor = bshell_line_ed_get_cursor(ed);
	if (cursor > 0) {
		fx_string_remove(buf, cursor - 1, 1);
		bshell_line_ed_move_cursor(ed, -1);
		bshell_line_ed_buffer_changed(ed);
	}

	return BSHELL_LINE_EDITOR_KEYBIND_RESULT(
		BSHELL_SUCCESS,
		BSHELL_LINE_EDITOR_KEYBIND_CONTINUE);
}

static struct bshell_line_ed_keybind_result generic_key(
	bshell_line_ed *ed,
	fx_keycode key)
{
	fx_wchar c = key;
	bool valid = fx_wchar_utf8_is_valid_scalar(c) && fx_wchar_is_graph(c);

	if (valid) {
		fx_string *buf = bshell_line_ed_get_buffer(ed);
		unsigned long cursor = bshell_line_ed_get_cursor(ed);
		char cstr[5] = {0};
		fx_string_insert_wc(buf, c, cursor);
		bshell_line_ed_move_cursor(ed, 1);
		bshell_line_ed_buffer_changed(ed);
	}

	return BSHELL_LINE_EDITOR_KEYBIND_RESULT(
		BSHELL_SUCCESS,
		BSHELL_LINE_EDITOR_KEYBIND_CONTINUE);
}

static enum bshell_status load(
	bshell_line_ed_plugin *plugin,
	bshell_line_ed *ed)
{
	struct bshell_line_ed_core_p *core
		= fx_object_get_private(plugin, BSHELL_TYPE_LINE_EDITOR_CORE);
	core->c_key_eof = bshell_line_ed_bind_key(ed, "^d", eof_key, 100);
	core->c_key_cursor_left
		= bshell_line_ed_bind_key(ed, "left", cursor_left, 100);
	core->c_key_cursor_right
		= bshell_line_ed_bind_key(ed, "right", cursor_right, 100);
	core->c_key_cursor_right
		= bshell_line_ed_bind_key(ed, "return", return_key, 100);
	core->c_key_generic
		= bshell_line_ed_bind_key(ed, "*", generic_key, 100);
	core->c_key_backspace
		= bshell_line_ed_bind_key(ed, "backspace", backspace, 100);

	return BSHELL_SUCCESS;
}

static enum bshell_status render_prompt(
	bshell_line_ed_plugin *plugin,
	bshell_line_ed *ed)
{
	fx_string *prompt = bshell_line_ed_get_prompt(ed);
	fx_tty *tty = bshell_line_ed_get_tty(ed);
	const char *s = fx_string_get_cstr(prompt);
	fx_tty_puts(tty, 0, s);
	return BSHELL_SUCCESS;
}

static enum bshell_status render_buffer(
	bshell_line_ed_plugin *plugin,
	bshell_line_ed *ed)
{
	fx_string *buf = bshell_line_ed_get_buffer(ed);
	fx_tty *tty = bshell_line_ed_get_tty(ed);
	const char *s = fx_string_get_cstr(buf);
	for (unsigned long i = 0; *s; i++) {
		fx_wchar c = fx_wchar_utf8_codepoint_decode(s);
		unsigned int stride = fx_wchar_utf8_codepoint_size(c);
		if (stride == 0) {
			break;
		}

		char cs[5] = {0};
		fx_wchar_utf8_codepoint_encode(c, cs);

		fx_tty_puts(tty, 0, cs);
		s += stride;
	}

	return BSHELL_SUCCESS;
}

static enum bshell_status get_data(
	bshell_line_ed_plugin *plugin,
	bshell_line_ed *ed,
	const char *key,
	fx_value *out)
{
	struct bshell_line_ed_core_p *core
		= fx_object_get_private(plugin, BSHELL_TYPE_LINE_EDITOR_CORE);
	const fx_value *v = fx_hashtable_get(core->c_data, &FX_CSTR(key));
	if (v) {
		fx_value_copy(out, v);
	} else {
		*out = FX_VALUE_EMPTY;
	}

	return BSHELL_SUCCESS;
}

static enum bshell_status put_data(
	bshell_line_ed_plugin *plugin,
	bshell_line_ed *ed,
	const char *key,
	const fx_value *value)
{
	struct bshell_line_ed_core_p *core
		= fx_object_get_private(plugin, BSHELL_TYPE_LINE_EDITOR_CORE);
	fx_hashtable_put(core->c_data, &FX_CSTR(key), (fx_value *)value);
	return BSHELL_SUCCESS;
}

FX_TYPE_CLASS_BEGIN(bshell_line_ed_core)
	FX_TYPE_VTABLE_INTERFACE_BEGIN(fx_object, FX_TYPE_OBJECT)
		FX_INTERFACE_ENTRY(to_string) = NULL;
	FX_TYPE_VTABLE_INTERFACE_END(fx_object, FX_TYPE_OBJECT)

	FX_TYPE_VTABLE_INTERFACE_BEGIN(
		bshell_line_ed_plugin,
		BSHELL_TYPE_LINE_EDITOR_PLUGIN)
		FX_INTERFACE_ENTRY(p_load) = load;
		FX_INTERFACE_ENTRY(p_render_prompt) = render_prompt;
		FX_INTERFACE_ENTRY(p_render_buffer) = render_buffer;
		FX_INTERFACE_ENTRY(p_get_data) = get_data;
		FX_INTERFACE_ENTRY(p_put_data) = put_data;
	FX_TYPE_VTABLE_INTERFACE_END(bshell_command, BSHELL_TYPE_COMMAND)
FX_TYPE_CLASS_END(bshell_line_ed_core)

FX_TYPE_DEFINITION_BEGIN(bshell_line_ed_core)
	FX_TYPE_ID(0xf5174a63, 0x8fe4, 0x4720, 0xa861, 0x4ebb0d170dd3);
	FX_TYPE_NAME("bshell.runtime.line_editor.plugins.core");
	FX_TYPE_EXTENDS(BSHELL_TYPE_LINE_EDITOR_PLUGIN);
	FX_TYPE_CLASS(bshell_line_ed_core_class);
	FX_TYPE_INSTANCE_INIT(init);
	FX_TYPE_INSTANCE_FINI(fini);
	FX_TYPE_INSTANCE_PRIVATE(struct bshell_line_ed_core_p);
FX_TYPE_DEFINITION_END(bshell_line_ed_core)