#ifndef LINE_ED_H_
#define LINE_ED_H_

#define LINE_MAX 4096

#include <blue/term/tty.h>
#include <blue/core/queue.h>
#include <blue/ds/array.h>
#include <ivy/line-source.h>
#include <stddef.h>

struct s_tty;
struct b_tty_vmode;

struct line_ed;

struct line_ed_hook {
	void (*hook_keypress)(struct line_ed *, struct line_ed_hook *, b_keycode);
	void (*hook_buffer_modified)(struct line_ed *, struct line_ed_hook *);
	b_queue_entry hook_entry;
};

enum line_ed_flags {
	/* always reprint an entire line when a character is added/deleted.
	 * without this flag, only the modified character any subsequent
	 * characters are reprinted. */
	LINE_ED_FULL_REPRINT = 0x01u,

	/* keep line continuation (backslash-newline) tokens in the output
	 * buffer (default behaviour) */
	LINE_ED_KEEP_CONTINUATIONS = 0x00u,
	/* convert line continuation tokens in the output buffer to simple
	 * linefeeds. */
	LINE_ED_CONVERT_CONTINUATIONS = 0x02u,
	/* remove line continuation tokens from the output buffer, so that all
	 * chars are on a single line */
	LINE_ED_REMOVE_CONTINUATIONS = 0x06u,
};

struct line_ed {
	enum line_ed_flags l_flags;

	/* array of basic prompt strings */
	const char *l_prompt[2];
	/* input buffer, pointer to the buffer cell that corresponds to
	 * the current cursor position, and pointer to the byte AFTER the last
	 * usable byte in the buffer */
	char *l_buf, *l_buf_ptr, *l_buf_end;
	/* pointer to the byte AFTER the last byte of the user's input */
	char *l_line_end;
	/* 2-dimensional coordinates of the current cursor position.
	 * this does NOT include any prompts that are visible on the terminal */
	size_t l_cursor_x, l_cursor_y;
	/* the number of line continuations that have been inputted */
	unsigned int l_continuations;

	struct ivy_line_source l_line_source;

	/* pointer to tty interface */
	b_tty *l_tty;

	/* the lexical scope that we are currently in.
	 * this is provided by components further up the input pipeline,
	 * for example, when we are inside a string or if-statement. */
	const char *l_scope_type;

	/* array of previously entered commands */
	b_array *l_history;
	/* index of the currently selected history entry */
	size_t l_history_pos;

	/* list of defined highlight ranges */
	b_queue l_hl_ranges;
	/* list of installed hooks */
	b_queue l_hooks;
};

extern struct line_ed *line_ed_create(void);
extern void line_ed_destroy(struct line_ed *ed);
extern void line_ed_set_flags(struct line_ed *ed, enum line_ed_flags flags);
extern void line_ed_set_scope_type(struct line_ed *ed, const char *scope_type);

extern void line_ed_put_highlight(
	struct line_ed *ed, unsigned long start_x, unsigned long start_y,
	unsigned long end_x, unsigned long end_y, const struct b_tty_vmode *vmode);
extern void line_ed_clear_highlights(struct line_ed *ed);
extern void line_ed_print_highlights(struct line_ed *ed);

extern void line_ed_add_hook(struct line_ed *ed, struct line_ed_hook *hook);
extern void line_ed_remove_hook(struct line_ed *ed, struct line_ed_hook *hook);

extern size_t line_ed_readline(struct line_ed *ed, char *out, size_t max);

static inline struct ivy_line_source *line_ed_to_line_source(struct line_ed *ed)
{
	return &ed->l_line_source;
}

#endif