#!/usr/bin/env bash

# Bash 4.0+ only. Faster than using tr or awk + no fork.
toLower() {
    if [[ $# -eq 0 ]]; then
        while IFS= read -r line; do
            echo "${line,,}"
        done
    else
        local str="$*"
        echo "${str,,}"
    fi
}

# Return a string corresponding to the current OS.
which_os() {
    case "$OSTYPE" in
    darwin*)
        printf "darwin"
        ;;
    linux*)
        if [[ -f /etc/os-release ]]; then
            # shellcheck disable=SC1091
            source /etc/os-release
            printf "%s" "${ID,,}"
        else
            printf "linux"
        fi
        ;;
    esac
}

# Choose a Charm repo name with Gum.
pickCharmRepo() {
    getCharmRepos | gum filter --height=10 --header "$1"
}

# Interactively choose a Charm repo.
charm_clone() {
    local repo
    repo="$(pickCharmRepo "Clone which Charm™ repo?")"
    if [[ -z "$repo" ]]; then
        printf "Okay, never mind.\n"
        return 1
    fi
    git clone "git@github.com:charmbracelet/$repo" "$HOME/src/$repo"
}

# Interactively use "go get" against a Charm repo.
go_get_charm() {
    local repo
    repo="$(pickCharmRepo "Which Charm™ repo do you want to ‘go get?’")"
    if [[ -z "$repo" ]]; then
        printf "Okay, never mind.\n"
        return 1
    fi
    go get "github.com/charmbracelet/$repo"
}

# Returns the number of CPU cores available on the system.
num_cores() {
    nproc 2>/dev/null || sysctl -n hw.ncpu 2>/dev/null || echo "Could not determine core count"
}

# Return 1 if a given command exists, and 0 if not.
command_exists() {
    if command -v "$1" &>/dev/null; then
        printf 1
        return
    fi
    printf 0
}

# Return the preferred diff tool for the given OS.
gitdiff() {
    if [[ $(which_os) == darwin ]]; then
        opendiff
    else
        vimdiff
    fi
}

#shellcheck disable=1090
decryptAndSource() {
    source <(gpg --decrypt "$1" 2>/dev/null)
}

# Print the names of all public and private Charm repos.
getCharmRepos() {
    getRepos() {
        gh repo list charmbracelet --visibility="$1" --json name
    }

    getAllRepos() {
        printf '%s %s' "$(getRepos "public")" "$(getRepos "private")" | jq -s 'add'
    }

    getAllRepos |
        jq .[].name |
        tr -d '"' |
        sort
}

# Git worktree helper.
# This is a function (not a script) because cd must affect the caller's shell.
# A script runs in a child process, so cd would only change the subshell.
# Usage:
#   wt <name>       create worktree + branch one level up from git root, cd into it
#   wt wipe [name]  destroy current (or named) worktree, cd back to main project
wt() {
    local subcmd="$1"

    if [[ -z "$subcmd" ]]; then
        echo "Usage: wt <name>       create worktree and branch <name>"
        echo "       wt wipe [name]  remove worktree and branch"
        return 1
    fi

    local root
    root="$(git rev-parse --show-toplevel 2>/dev/null)"
    if [[ -z "$root" ]]; then
        echo "Not in a git repository" >&2
        return 1
    fi

    local parent
    parent="$(dirname "$root")"

    if [[ "$subcmd" == "wipe" ]]; then
        local name="$2"
        if [[ -z "$name" ]]; then
            name="$(basename "$PWD")"
        fi
        local target="$parent/$name"
        local main_dir="$parent/main"

        if [[ ! -d "$target" ]]; then
            echo "Worktree directory '$target' not found" >&2
            return 1
        fi

        if ! gum confirm "Remove worktree and branch '$name'?"; then
            return 0
        fi

        if ! git worktree remove "$target" --force 2>/dev/null; then
            echo "Failed to remove worktree" >&2
            return 1
        fi

        git branch -D "$name" 2>/dev/null

        if [[ "$PWD" == "$target" || "$PWD" == "$target"* ]]; then
            cd "$main_dir" || return 1
        fi
        return 0
    fi

    local name="$subcmd"
    local target="$parent/$name"

    if [[ "$name" == "wipe" ]]; then
        echo "Cannot create a worktree named 'wipe'" >&2
        return 1
    fi

    if [[ -d "$target" ]]; then
        echo "Directory '$target' already exists" >&2
        return 1
    fi

    if git show-ref --verify --quiet "refs/heads/$name" 2>/dev/null; then
        # Local branch exists, use it
        if ! git worktree add "$target" "$name"; then
            return 1
        fi
    elif git show-ref --verify --quiet "refs/remotes/origin/$name" 2>/dev/null; then
        # Remote branch exists on origin, use it
        if ! git worktree add "$target" "origin/$name"; then
            return 1
        fi
    else
        # New branch
        if ! git worktree add -b "$name" "$target" HEAD; then
            return 1
        fi
    fi

    cd "$target" || return 1
}