local M = {}

local Path = require('plenary.path')

local cached_history = nil

local prompt_before_history = nil

M.index = nil

local function get_history_file()

local data_path = Path:new(vim.fn.stdpath('data')):joinpath('opencode')

if not data_path:exists() then

data_path:mkdir({ parents = true })

end

return data_path:joinpath('history.txt')

end

M.write = function(prompt)

local history = M.read()

if #history > 0 and history[1] == prompt then

return

end

local file = io.open(get_history_file().filename, 'a')

if file then

-- Escape any newlines in the prompt

local escaped_prompt = prompt:gsub('\n', '\\n')

file:write(escaped_prompt .. '\n')

file:close()

-- Invalidate cache when writing new history

cached_history = nil

end

end

M.read = function()

-- Return cached result if available

if cached_history then

return cached_history

end

local line_by_index = {}

local file = io.open(get_history_file().filename, 'r')

if file then

local lines = {}

-- Read all non-empty lines

for line in file:lines() do

if line:gsub('%s', '') ~= '' then

-- Unescape any escaped newlines

local unescaped_line = line:gsub('\\n', '\n')

table.insert(lines, unescaped_line)

end

end

file:close()

-- Reverse the array to have index 1 = most recent

for i = 1, #lines do

line_by_index[i] = lines[#lines - i + 1]

end

end

-- Cache the result

cached_history = line_by_index

return line_by_index

end

M.prev = function()

local history = M.read()

if not M.index or M.index == 0 then

prompt_before_history = require('opencode.state').input_content

end

-- Initialize or increment index

M.index = (M.index or 0) + 1

-- Cap at the end of history

if M.index > #history then

M.index = #history

end

return history[M.index]

end

M.next = function()

-- Return nil for invalid cases

if not M.index then

return nil

end

if M.index <= 1 then

M.index = nil

return prompt_before_history

end

M.index = M.index - 1

return M.read()[M.index]

end

---Delete specific entries from history by their indices

---@param indices number[] Array of 1-based indices to delete

M.delete = function(indices)

if not indices or #indices == 0 then

return false

end

local history = M.read()

if #history == 0 then

return false

end

-- Sort indices in descending order to avoid index shifting issues

local sorted_indices = {}

for _, idx in ipairs(indices) do

if idx > 0 and idx <= #history then

table.insert(sorted_indices, idx)

end

end

table.sort(sorted_indices, function(a, b)

return a > b

end)

for _, idx in ipairs(sorted_indices) do

table.remove(history, idx)

end

return M._write_history(history)

end

---Clear all history entries

M.clear = function()

return M._write_history({})

end

---Internal function to write history array to file

---@param history_array table Array of history entries to write

---@return boolean success Whether the write operation succeeded

M._write_history = function(history_array)

local file = io.open(get_history_file().filename, 'w')

if not file then

return false

end

for i = #history_array, 1, -1 do

local entry = history_array[i]

if entry and entry ~= '' then

local escaped_entry = entry:gsub('\n', '\\n')

file:write(escaped_entry .. '\n')

end

end

file:close()

cached_history = nil

return true

end

return M