local api = vim.api
local wk = require('which-key')

-- No one likes Esc
api.nvim_set_keymap('i', 'jk', [[<Esc>]], {noremap = true, silent = true})

-- Escape to normal mode in terminal buffer
api.nvim_set_keymap('t', '<Esc>', '<C-\\><C-n>', {noremap = true, silent = true})

-- Continuous indent
api.nvim_set_keymap('v', '<', '<gv', {noremap = true, silent = true})
api.nvim_set_keymap('v', '>', '>gv', {noremap = true, silent = true})

-- Clear search results
-- api.nvim_set_keymap('n', '<Esc>', '<Cmd>noh<CR>', {noremap = true, silent = true})

-----------------
-- Normal mode --
-----------------
wk.register({
    -- Better Y
    Y = {'y$', 'Yank to eol'},

    -- Easier start and end of line
    H = {'^', 'Start of the line'},
    L = {'$', 'End of the line'},

    -- Easier moving between windows
    ['<C-h>'] = {'<C-w>h', 'Go to the left window'},
    ['<C-l>'] = {'<C-w>l', 'Go to the right window'},
    ['<C-j>'] = {'<C-w>j', 'Go to the down window'},
    ['<C-k>'] = {'<C-w>k', 'Go to the up window'},

    -- Copy the whole buffer
    ['<C-a>'] = {'<Cmd>%y+<CR>', 'Copy whole buffer'},

    -- 'Legacy' save buffer
    -- ['<C-s>'] = {':w<CR>', 'Write buffer'},

    -- Close buffer
    ['<C-x>'] = {':bd!<CR>', 'Close buffer'},

    -- Remove trailing whitespace
    ['<A-w>'] = {':%s/\\s\\+$//e<CR>', 'Remove trailing'},

    -- Resize buffer
    ['<A-j>'] = {':resize -2<CR>', 'Resize vertical -2'},
    ['<A-k>'] = {':resize +2<CR>', 'Resize vertical +2'},
    ['<A-h>'] = {':vertical resize -2<CR>', 'Resize horizontal -2'},
    ['<A-l>'] = {':vertical resize +2<CR>', 'Resize horizontal +2'},

    -- Switch between tabs and spaces
    ['<A-t>'] = {
        function()
            if vim.o.expandtab == true then
                vim.cmd('set noexpandtab nosmarttab softtabstop& shiftwidth&')
                vim.cmd('echomsg "Switched to indent with tabs"')
            else
                vim.opt.expandtab = true
                vim.opt.smarttab = true
                vim.opt.softtabstop = 4
                vim.opt.shiftwidth = 4
                vim.cmd('echomsg "Switched to indent with 4 spaces"')
            end
        end,
        'Switch indent style'
    },

    -- Naming common keys
    ['['] = {name = 'Block motions (previous)'},
    [']'] = {name = 'Block motions (next)'},
    g = {name = 'Goto motions'},
    z = {name = 'Misc utils'},

    -- Don't need to show bufferline numbers
    ['<leader>1'] = 'which_key_ignore',
    ['<leader>2'] = 'which_key_ignore',
    ['<leader>3'] = 'which_key_ignore',
    ['<leader>4'] = 'which_key_ignore',
    ['<leader>5'] = 'which_key_ignore',
    ['<leader>6'] = 'which_key_ignore',
    ['<leader>7'] = 'which_key_ignore',
    ['<leader>8'] = 'which_key_ignore',
    ['<leader>9'] = 'which_key_ignore',

    -- Move between tabs
    ['<TAB>'] = {'<Cmd>BufferLineCycleNext<CR>', 'Next buffer'},
    ['<S-TAB>'] = {'<Cmd>BufferLineCyclePrev<CR>', 'Previous buffer'},

    -- NvimTree
    ['<C-n>'] = {':NvimTreeToggle<CR>', 'NvimTree'},

    -- ToggleTerm
    ['<C-\\>'] = {':ToggleTerm<CR>', 'Toggle terminal'}
})

-----------------------------------
-- Normal mode (with leader key) --
-----------------------------------
wk.register({
    c = {':ColorizerToggle<CR>', 'Toggle colorizer'},

    b = {
        name = 'Buffer',
        n = {':DashboardNewFile<CR>', 'New file'}
    },

    -- Telescope
    f = {
        name = 'Telescope',
        a = {':Telescope autocommands<CR>', 'Autocommands'},
        b = {':Telescope buffers<CR>', 'Buffers'},
        c = {':Telescope commands<CR>', 'Commands'},
        e = {':Telescope file_browser<CR>', 'File browser'},
        f = {':Telescope find_files<CR>', 'Find files'},
        g = {':Telescope live_grep<CR>', 'Live grep'},
        h = {':Telescope help_tags<CR>', 'Help tags'},
        i = {':Telescope highlights<CR>', 'Highlight groups'},
        j = {':Telescope symbols<CR>', 'Pick emojis'},
        k = {':Telescope keymaps<CR>', 'Normal keymaps'},
        m = {':Telescope marks<CR>', 'Bookmarks'},
        o = {':Telescope oldfiles<CR>', 'Recent files'},
        p = {':Telescope man_pages<CR>', 'Man pages'},
        r = {':Telescope reloader<CR>', 'Reload lua modules'},
        s = {':Telescope treesitter<CR>', 'Treesitter'},
        t = {':Telescope<CR>', 'Telescope'},
        u = {':Telescope current_buffer_fuzzy_find<CR>', 'Search current buffer'},
        v = {':Telescope vim_options<CR>', 'Vim options'},
        y = {':Telescope filetypes<CR>', 'Filetypes'},
        z = {':Telescope registers<CR>', 'Vim registers'}
    },

    l = {
        name = 'LSP'
    },

    -- Git
    g = {
        name = 'Git',
        b = 'Blame current line',
        j = 'Next hunk',
        k = 'Previous hunk',
        p = 'Preview hunk',
        r = 'Reset hunk',
        R = 'Reset all hunks in buffer',
        s = 'Stage hunk',
        u = 'Undo hunk',
        n = {':Neogit<CR>', 'Neogit'},
        f = {
            name = 'Telescope',
            a = {':Telescope git_stash<CR>', 'Stash'},
            b = {':Telescope git_bcommits<CR>', 'Buffer commits'},
            c = {':Telescope git_commits<CR>', 'Commits'},
            m = {':Telescope git_branches<CR>', 'Branches'},
            s = {':Telescope git_status<CR>', 'Status'}
        }
    },

    -- Tab related
    t = {
        name = 'Tab',
        n = {'<Cmd>tabnext<CR>', 'Next tab'},
        p = {'<Cmd>tabprev<CR>', 'Previous tab'},
        t = {'<Cmd>tabnew<CR>', 'New tab'}
    }
}, {prefix = '<leader>'})

-----------------------------------
-- Visual mode (with leader key) --
-----------------------------------
wk.register({
    -- GitSigns
    g = {
        name = 'Git',
        r = 'Reset hunk',
        s = 'Stage hunk'
    }
}, {mode = 'v', prefix = '<leader>'})

----------------
-- nvim-compe --
----------------
-- Use (S-)Tab in completion menu
-- See https://github.com/L3MON4D3/Luasnip/issues/1#issuecomment-835241958
local t = function(str)
    return vim.api.nvim_replace_termcodes(str, true, true, true)
end

local function prequire(...)
    local status, lib = pcall(require, ...)
    if (status) then return lib end
    return nil
end

local luasnip = prequire('luasnip')

local check_back_space = function()
    local col = vim.fn.col('.') - 1
    return col == 0 or vim.fn.getline('.'):sub(col, col):match('%s') ~= nil
end

_G.tab_complete = function()
    if vim.fn.pumvisible() == 1 then
        return t '<C-n>'
    elseif luasnip and luasnip.expand_or_jumpable() then
        return t '<Plug>luasnip-expand-or-jump'
    elseif check_back_space() then
        return t '<Tab>'
    else
        return vim.fn['compe#complete']()
    end
end
_G.s_tab_complete = function()
    if vim.fn.pumvisible() == 1 then
        return t '<C-p>'
    elseif luasnip and luasnip.jumpable(-1) then
        return t '<Plug>luasnip-jump-prev'
    else
        return t '<S-Tab>'
    end
end

vim.api.nvim_set_keymap('i', '<Tab>', 'v:lua.tab_complete()', {expr = true, noremap = true, silent = true})
vim.api.nvim_set_keymap('s', '<Tab>', 'v:lua.tab_complete()', {expr = true, noremap = true, silent = true})
vim.api.nvim_set_keymap('i', '<S-Tab>', 'v:lua.s_tab_complete()', {expr = true, noremap = true, silent = true})
vim.api.nvim_set_keymap('s', '<S-Tab>', 'v:lua.s_tab_complete()', {expr = true, noremap = true, silent = true})

vim.api.nvim_set_keymap('i', '<C-Space>', 'compe#complete()', {expr = true, noremap = true, silent = true})
vim.api.nvim_set_keymap('i', '<C-e>', 'compe#close(\'<C-e>\')', {expr = true, noremap = true, silent = true})