(defvar llm-tools--hl-bigrams
  (list "aa" "ab" "ac" "ad" "ae" "af" "ag" "ah" "ai" "aj" "ak" "al" "am" "an"
	"ao" "ap" "aq" "ar" "as" "at" "au" "av" "aw" "ax" "ay" "az" "ba" "bb"
	"bc" "bd" "be" "bf" "bg" "bh" "bi" "bj" "bk" "bl" "bm" "bn" "bo" "bp"
	"br" "bs" "bt" "bu" "bv" "bw" "bx" "by" "bz" "ca" "cb" "cc" "cd" "ce"
	"cf" "cg" "ch" "ci" "cj" "ck" "cl" "cm" "cn" "co" "cp" "cq" "cr" "cs"
	"ct" "cu" "cv" "cw" "cx" "cy" "cz" "da" "db" "dc" "dd" "de" "df" "dg"
	"dh" "di" "dj" "dk" "dl" "dm" "dn" "do" "dp" "dq" "dr" "ds" "dt" "du"
	"dv" "dw" "dx" "dy" "dz" "ea" "eb" "ec" "ed" "ee" "ef" "eg" "eh" "ei"
	"ej" "ek" "el" "em" "en" "eo" "ep" "eq" "er" "es" "et" "eu" "ev" "ew"
	"ex" "ey" "ez" "fa" "fb" "fc" "fd" "fe" "ff" "fg" "fh" "fi" "fj" "fk"
	"fl" "fm" "fn" "fo" "fp" "fq" "fr" "fs" "ft" "fu" "fv" "fw" "fx" "fy"
	"fz" "ga" "gb" "gc" "gd" "ge" "gf" "gg" "gh" "gi" "gj" "gl" "gm" "gn"
	"go" "gp" "gr" "gs" "gt" "gu" "gv" "gw" "gx" "gy" "gz" "ha" "hb" "hc"
	"hd" "he" "hf" "hg" "hh" "hi" "hj" "hk" "hl" "hm" "hn" "ho" "hp" "hq"
	"hr" "hs" "ht" "hu" "hv" "hw" "hx" "hy" "hz" "ia" "ib" "ic" "id" "ie"
	"if" "ig" "ih" "ii" "ij" "ik" "il" "im" "in" "io" "ip" "iq" "ir" "is"
	"it" "iu" "iv" "iw" "ix" "iy" "iz" "ja" "jb" "jc" "jd" "je" "jf" "jg"
	"jh" "ji" "jj" "jk" "jl" "jm" "jn" "jo" "jp" "jq" "jr" "js" "jt" "ju"
	"jw" "jx" "jy" "ka" "kb" "kc" "kd" "ke" "kf" "kg" "kh" "ki" "kj" "kk"
	"kl" "km" "kn" "ko" "kp" "kr" "ks" "kt" "ku" "kv" "kw" "kx" "ky" "la"
	"lb" "lc" "ld" "le" "lf" "lg" "lh" "li" "lj" "lk" "ll" "lm" "ln" "lo"
	"lp" "lr" "ls" "lt" "lu" "lv" "lw" "lx" "ly" "lz" "ma" "mb" "mc" "md"
	"me" "mf" "mg" "mh" "mi" "mj" "mk" "ml" "mm" "mn" "mo" "mp" "mq" "mr"
	"ms" "mt" "mu" "mv" "mw" "mx" "my" "mz" "na" "nb" "nc" "nd" "ne" "nf"
	"ng" "nh" "ni" "nj" "nk" "nl" "nm" "nn" "no" "np" "nr" "ns" "nt" "nu"
	"nv" "nw" "nx" "ny" "nz" "oa" "ob" "oc" "od" "oe" "of" "og" "oh" "oi"
	"oj" "ok" "ol" "om" "on" "oo" "op" "oq" "or" "os" "ot" "ou" "ov" "ow"
	"ox" "oy" "oz" "pa" "pb" "pc" "pd" "pe" "pf" "pg" "ph" "pi" "pj" "pk"
	"pl" "pm" "pn" "po" "pp" "pq" "pr" "ps" "pt" "pu" "pv" "pw" "px" "py"
	"pz" "qa" "qb" "qc" "qd" "qe" "qh" "qi" "ql" "qm" "qn" "qo" "qp" "qq"
	"qr" "qs" "qt" "qu" "qw" "qx" "qy" "ra" "rb" "rc" "rd" "re" "rf" "rg"
	"rh" "ri" "rk" "rl" "rm" "rn" "ro" "rp" "rq" "rr" "rs" "rt" "ru" "rv"
	"rw" "rx" "ry" "rz" "sa" "sb" "sc" "sd" "se" "sf" "sg" "sh" "si" "sj"
	"sk" "sl" "sm" "sn" "so" "sp" "sq" "sr" "ss" "st" "su" "sv" "sw" "sx"
	"sy" "sz" "ta" "tb" "tc" "td" "te" "tf" "tg" "th" "ti" "tj" "tk" "tl"
	"tm" "tn" "to" "tp" "tr" "ts" "tt" "tu" "tv" "tw" "tx" "ty" "tz" "ua"
	"ub" "uc" "ud" "ue" "uf" "ug" "uh" "ui" "uj" "uk" "ul" "um" "un" "uo"
	"up" "uq" "ur" "us" "ut" "uu" "uv" "uw" "ux" "uy" "uz" "va" "vb" "vc"
	"vd" "ve" "vf" "vg" "vh" "vi" "vj" "vk" "vl" "vm" "vn" "vo" "vp" "vq"
	"vr" "vs" "vt" "vu" "vv" "vw" "vx" "vy" "vz" "wa" "wb" "wc" "wd" "we"
	"wf" "wg" "wh" "wi" "wj" "wk" "wl" "wm" "wn" "wo" "wp" "wr" "ws" "wt"
	"wu" "wv" "ww" "wx" "wy" "xa" "xb" "xc" "xd" "xe" "xf" "xh" "xi" "xl"
	"xm" "xn" "xo" "xp" "xr" "xs" "xt" "xu" "xx" "xy" "xz" "ya" "yb" "yc"
	"yd" "ye" "yf" "yg" "yh" "yi" "yj" "yk" "yl" "ym" "yn" "yo" "yp" "yr"
	"ys" "yt" "yu" "yv" "yw" "yx" "yy" "yz" "za" "zb" "zc" "zd" "ze" "zf"
	"zg" "zh" "zi" "zk" "zl" "zm" "zn" "zo" "zp" "zr" "zs" "zt" "zu" "zw"
	"zx" "zy" "zz")
  "List of bigrams for use with hashline reads/writes.

Each of the bigrams resolve to a single token in standard LLM
vocabulary, unlike a hash's hex digits.

Taken from https://github.com/can1357/oh-my-pi.
Precisely: https://raw.githubusercontent.com/can1357/oh-my-pi/85003ca/packages/coding-agent/src/hashline/bigrams.json")

(defun llm-tools--hl-hash (line)
  (elt llm-tools--hl-bigrams (% (sxhash line) 647)))

(defun llm-tools--hl-file-lines (file &optional beg end)
  "Return FILE contents as a list of strings.
With optional BEG and END (inclusive, 1-based), return the lines between that range."
  (with-temp-buffer
    (insert-file-contents-literally file)
    (let ((lines (string-lines (buffer-string))))
      (if beg
	  (cl-subseq lines (1- beg) end)
	lines))))

(defun llm-tools--hl-format-lines (lines &optional start include-content?)
  "Format LINES in hashline format.
START is 1-based (default 1).
If INCLUDE-CONTENT is non-nil, append `|LINE' after each hash."
  (string-join
   (cl-mapcar (lambda (line i)
		(if include-content?
		    (format "%d%2s|%s" i (llm-tools--hl-hash line) line)
		  (format "%d%2s" i (llm-tools--hl-hash line))))
	      lines
	      (number-sequence (or start 1) (+ (or start 1) (1- (length lines)))))
   "\n"))

(defun llm-tools--hl-file-read (file)
  "Return FILE contents in hashline format."
  (llm-tools--hl-format-lines (llm-tools--hl-file-lines file) nil t))

(defun llm-tools--hl-file-read-range (file beg end)
  "Return FILE contents in hashline format from lines BEG to END."
  (llm-tools--hl-format-lines (llm-tools--hl-file-lines file beg end) beg t))

;; FIXME might be redundant with =llm-tools--hl-file-line-hash= if I'm only
;; verifying the hash of the anchors and telling LLM to re-read the
;; file when they don't match
(defun llm-tools--hl-file-read-hashes (file)
  "Return FILE contents in hashline format without content."
  (llm-tools--hl-format-lines (llm-tools--hl-file-lines file)))

(defun llm-tools--hl-file-line-hash (file n)
  "Return the hash of the Nth line in FILE."
  (let ((lines (llm-tools--hl-file-lines file)))
      (llm-tools--hl-hash (elt lines (1- n)))))

;; before applying patch, first read the file to see if there were any changes
;; if the llm's replacement text's hashlines do not match current hashlines, reject the request
;; maybe if it just shifted a little bit (since the anchor is line number and hash of the line's content), there can be some kind of autohealing?
;; rather, the llm would not format it like the reads. it's just going to provide text according to what the anchors it gives say
;; so I just need to verify if the anchors didn't change

(provide 'llm-tools-hl)