local git = require("git")
local log = require("log")
local repo = require("git.repo")
local util = require("util")

local M = {}

local LOG_FORMAT = "%h %ad {%an}%d %s"
local DEFAULT_MAX_COUNT = 1000

---@class ow.Git.LogOpts
---@field max_count integer?  cap on commits to show. Nil uses the default, <= 0 means "all"

---@param opts ow.Git.LogOpts?
function M.show(opts)
    opts = opts or {}
    local max_count = opts.max_count
    if max_count == nil then
        max_count = DEFAULT_MAX_COUNT
    end

    local _, worktree = repo.resolve_cwd()
    if not worktree then
        log.warning("not in a git repository")
        return
    end

    local cmd = {
        "git",
        "log",
        "--graph",
        "--all",
        "--decorate",
        "--date=short",
        "--format=format:" .. LOG_FORMAT,
    }
    if max_count > 0 then
        table.insert(cmd, "--max-count=" .. max_count)
    end

    local result = vim.system(cmd, { cwd = worktree, text = true }):wait()
    if result.code ~= 0 then
        log.error("git log failed: %s", vim.trim(result.stderr or ""))
        return
    end

    local buf = git.new_scratch()
    vim.b[buf].git_worktree = worktree
    vim.bo[buf].modifiable = true
    vim.api.nvim_buf_set_lines(
        buf,
        0,
        -1,
        false,
        util.split_lines(result.stdout or "")
    )
    vim.bo[buf].modifiable = false
    vim.bo[buf].modified = false
    vim.bo[buf].filetype = "gitlog"
end

return M